Adobe Photoshop CS3 for Photographers phần 3 doc

Display calibration and profi ling We now need to focus on what is the most important aspect of any Photoshop system: getting the monitor to correctly display your images in Photoshop at

the screens directly The window is north facing, so I never have any problems with direct sunlight entering the room and what daylight does enter the offi ce can be controlled with the venetian blind It is also important to choose a chair that is comfortable, ideally one with arm rests and adjustable seating positions so that your wrists can rest comfortably on the table top The monitor should be level with your line of view or slightly lower

Once you start building an imaging workstation, you will soon end up with lots of electrical devices While these in themselves may not consume a huge amount of power, do take precautions against too many power leads trailing off from a single power point Cathode ray tube monitors are vulnerable to damage from the magnets in

an unshielded speaker or the electrical motor in an inkjet printer Just try not to position any item other than the computer too close to a CRT monitor screen Interference from other electrical items can cause problems too To prevent damage or loss of data from a sudden power cut, place an uninterruptible power supply unit between your computer and the mains source These devices will also smooth out any voltage spikes or surges in the electricity supply

Choosing a display

The display is one of the most important components in your entire kit It is what you will spend all your time looking at as you work in Photoshop You really do not want to economize by buying a cheap screen that is unsuited for graphics use There are two types of display that you can buy: cathode ray tube (CRT) monitors and liquid crystal displays (LCDs) A cathode ray tube fi res electrons from its red, green and blue guns to produce a color image as the electrons strike the colored phosphor screen CRTs have been around a long time and they remain popular with high-end graphics users This is because most CRT displays make it possible to manually adjust the calibration of the display (see page 103) so that you can achieve a nice, neutral-looking output and

Chip speed

Microchip processing speed is expressed

in megahertz, but performance speed

also depends on the chip type A 2 GHz

Pentium class 4 chip is not as fast as a

2 GHz Intel Duo Core processsor Speed

comparisons in terms of the number of

megahertz are only valid between chips

of the same series Many of the latest

computers are also enabled with twin

processing And another crucial factor is

the bus speed This refers to the speed

of data transfer from RAM memory to the

CPU (the central processing unit, i.e the

chip) CPU performance can be restricted

by slow system bus speeds so faster is

better, especially for Photoshop work

where large chunks of data are always

being processed

there is less further adjustment required with the monitor profi le So ideally, the monitor profi le will simply fi ne-tune the image to appear correctly on the calibrated CRT

But because CRT displays are analog devices, they are prone to fl uctuate in performance and output This is why you must always calibrate a CRT monitor regularly The hardware controls of a CRT will typically allow you to adjust the contrast, brightness and color balance of the display output The more expensive CRT monitors such

as the Barco Calibrator have built-in self-calibrating tools

These continually monitor and regulate the output from the moment you switch the device on A 22" CRT display

is a big and bulky piece of equipment, whereas the light, slim-line design of a fl at panel LCD screen will occupy less desk space LCDs range in size from the screens used

on a laptop computer to big 30" desktop displays An LCD contains a translucent fi lm of fi xed-size liquid crystal elements that individually fi lter the color of a backlit,

fl uorescent light source Therefore, the only hardware adjustment you can usually make is to adjust the brightness

of the backlit screen You can calibrate the brightness of the LCD hardware but that is about all you can do The contrast is fi xed, but it is usually more contrasty than a typical CRT monitor, which is not a bad thing when doing Photoshop work for print output

Because LCDs are digital devices they tend to produce

a more consistent color output They still need to be calibrated and profi led, but the display’s performance will remain fairly consistent over longer periods of time On the other hand, there will be some variance in the image appearance depending on the angle from which you view the screen The brightness and color output of an LCD will only appear to be correct when the screen is viewed front

on And this very much depends on the design of the LCD display The worst examples of this can be seen on ultra-thin laptop display screens But the evenness of the output from a 23" Apple Cinema display and other desktop LCD screens is certainly a lot more consistent

Using a second display

If you are able to run two displays from your computer, then you might want to invest in a second, smaller screen and have this located beside the main display and use it to show the Photoshop palette windows and keep the main screen area clear of palette clutter To run a second display you may need to buy an additional PCI card that provides a second video port

Floating windows

In the past, PC users were restricted by the limits of the Photoshop application window This is now resolved in two ways

Firstly, because Bridge is now a separate application, it is no longer constrained to working in Photoshop, as we were with the File Browser And secondly, Photoshop has a fl oating windows feature in the PC version which lets you move document windows outside the bounds of the application window

It is interesting to speculate what displays will look like in the future BrightSide Technologies (www.

brightsidetech.com) has developed an LCD display which uses a matrix of LED lights instead of a fl uorescent light source to pass light through the LCD fi lm These displays have an incredible dynamic range and are capable of displaying a 16-bit per channel image with an illumination range that makes an ordinary 8-bit display look dull and fl at

by comparison We may one day have display technologies that are able to get closer to simulating the dynamic range

of natural light These will be great for viewing computer games and video, but for Photoshop print work we will mostly want to have the display we are looking at match our expectations of what can be reproduced on a print

Display calibration and profi ling

We now need to focus on what is the most important aspect

of any Photoshop system: getting the monitor to correctly display your images in Photoshop at the right brightness and neutralized to avoid introducing color casts This basic setup advice should be self-evident, because we all want our images in Photoshop to be consistent from session to session and match in appearance when they are viewed

on another user’s system There are several ways that you can go about this At a bare minimum you will want to calibrate the monitor display so that the contrast is turned

up to maximum, that the brightness is consistent with what everyone else would be using and that neutral grays really

do display as gray on the screen As I mentioned earlier, CRT displays will fl uctuate in performance all the time

So before you calibrate a CRT monitor, it should be left switched on for at least half an hour to give it a chance to warm up properly and stabilize A decent CRT monitor will have hardware controls that allow you to adjust the brightness and the color output from the individual color guns so that you can easily correct for color shifts and reset the gray balance of the output However, the life-span of a CRT is about three years and as these devices get older they will lose their brightness and contrast to the point where

Video cards

The graphics card in your computer is

what drives the display It processes all the

pixel information and converts it to draw a

color image on the screen An accelerated

graphics card will enable your screen

to do several things It will allow you to

run your screen display at higher screen

resolutions, hold more image screen

view data in memory and it will use the

monitor profi le information to fi nely adjust

the color appearance When more of the

off-screen image data remains in memory

the image scrolling is enhanced and this

provides generally faster screen refreshes

In the old days, computers were sold with

a limited amount of video memory If you

were lucky you could just about manage

to run a small screen in millions of colors

If you buy a computer today the chances

are that it will already be equipped with

a good, high performance graphics card,

easily capable of doing all of the above

These cards will contain 128 MB (or more)

of dedicated memory There is probably

not much advantage to be gained in fi tting

anything other than this (unless you have

a very large LCD screen) because the top

of the range graphics cards are mostly

optimized to provide faster 3D games

performance rather than providing a better

2D display

they can no longer be successfully calibrated or be reliable enough for Photoshop image editing.

The initial calibration process should get your display close to an idealized state From there, you can build a monitor profi le which at a minimum describes the black point, white point and chosen gamma The black point describes the darkest black that can be displayed so that the next lightest tone of dark gray is just visible The white point information tells the video card how to display

a pure white on the screen that matches the specifi ed color temperature For a CRT displays I suggest you use D65/6500 For LCD displays I suggest you select the native white point And lastly the gamma This tells the video card how much to adjust the midtone levels compensation

Note that the gamma you choose when creating a monitor profi le does not affect how light or dark an image will be displayed in Photoshop The monitor profi le gamma only affects how the midtone levels are distributed Whether you use a Mac or PC computer, you should always choose

a gamma of 2.2 when building a monitor profi le If you use a measuring instrument (see Figure 3.3) to accurately calibrate and profi le the display, you can build a monitor profi le that will contain a lot more detailed information about how the screen is able to display a broad range of colors

Basically, the calibration process should reset your hardware to a standardized output Next, you build a monitor profi le that describes how well the display actually performs after it has been calibrated A good CRT monitor will let you manually adjust the color output of the individual guns (smart monitors like the Sony Artisan and Barco Calibrator do this automatically) If the screen

is more or less neutral after calibration there is less further adjustment required to get a perfectly profi led display

The monitor profi le sends instructions to the video card

to fi ne-tune the display If these adjustments are relatively minor, you are making full use of the video card to describe

a full range of colors on the screen If you rely on video card adjustments to calibrate the display as well, then the

Figure 3.2 This is a screen shot showing the

hardware monitor controls for the LaCie Electron Blue III CRT display The hardware controls enable me to adjust the output of the individual guns that control the red, green and blue color of the display I adjust these settings as part of the display calibration process to make the screen neutral before building the monitor profi le.

Prolonging the life of a CRT display

A CRT display will typically provide three years of good use before the tube starts

to fade and calibration becomes diffi cult, although using a screen saver will help prolong the life of a CRT A CRT monitor display will usually have hardware controls that allow you to confi gure the alignment

of the image It is suggested that you carefully confi gure the alignment so that you don’t have the display image fi lling the entire area of the CRT screen Use the hardware controls to reduce the width and height slightly so that you have, say,

a quarter inch unused border around the display viewing area

video card is having to make bigger adjustments and the color output may suffer as a result For example, with a CRT display you can use the monitor hardware controls

to regulate and neutralize the color output via the video card Not all CRT monitors are capable of doing this and LCD displays certainly don’t The only adjustment you can make on an LCD monitor is to adjust the brightness This

is not to say that all LCD screens are unsuitable devices for graphics work The lower grade LCD displays such

as those used on laptop computers are not really good enough for Photoshop color work But the higher grade LCD screens will feature relatively good viewing angle consistency, are not too far off from providing a neutral color and D65 white balance and won’t fl uctuate much in performance As with everything else in life, you get what you pay for If you are not going to invest in a calibration/

measuring device, your best option with an LCD is to load

a canned profi le for your monitor and keep your fi ngers crossed It will sort of work and is better than doing nothing But I do urge you to consider buying a monitor and calibration device as a complete package

Calibration hardware

Let’s now look at the practical steps for calibrating and profi ling the display First, get rid of any distracting background colors or patterns on the computer desktop

And consider choosing a neutral color theme for your operating system The Mac OS X system has a graphite appearance setting especially there for Photoshop users!

If you are using a PC, try going to Control Panels ➯ Appearance ➯ Themes, choose Display and click the Appearance tab Click on the active and inactive window samples and choose a gray color for both If you are using Windows XP, try choosing the silver color scheme This is all very subjective of course, but personally I think these adjustments improve the system appearances

The only reliable way to calibrate and profi le your display is by using a hardware calibration system Some displays, such as the LaCie range can be bought with a

Eizo ColorEdge

Eizo have established themselves as

offering the fi nest quality LCD displays for

graphics use The ColorEdge CG221 is

the fl agship model in the range Capable

of providing uniform screen display

from edge to edge, it encompasses

the Adobe RGB gamut and comes with

ColorNavigator calibration software

that can be used with Gretag MacBeth

calibration devices This display is more

expensive than most, but is highly prized

for its color fi delity

Figure 3.3 The Gretag Macbeth Eye-One is a

popular spectrophotometer that can be used to

accurately measure the output from the monitor

display to both calibrate the output and, using the

accompanying Eye-One software, measure color

patches and build an ICC profi le for your display.

1 An uncalibrated and unprofi led monitor cannot be relied on to

provide an accurate indication of how colors should look

2 The calibration process simply aims to optimize the display for

gray balance, contrast and brightness.

3 The profi ling process records at a minimum the black point,

white point, and gamma With the right software, the profi ling process will also measure how a broad range of colors is displayed Recording this extra color information is the only way you can truly produce an accurate profi le

4 To create a profi le of this kind you need a colorimeter device

A calibrator such as the Gretag Macbeth Eye-One Display 2 or Eye-One Photo with the Eye-One Match 3.0 or Profi le Maker 5 Professional software will produce the most accurate results

bundled hardware calibrator, but there are many other types of stand-alone calibration packages to consider The ColorVision Monitor Spyder and Spyder2Pro Studio are affordable, and are sold either with PhotoCal or the more advanced OptiCal software The Monitor Spyders are colorimeter devices and can be used to measure the output from a CRT or LCD monitor display The X-Rite is also

a good system and comes with the easy-to-use Monaco OPTIX software

CRT measuring devices generally use rubber suckers

to attach to the screen, but to measure an LCD display, a weighted strap is used to counterbalance the instrument

so it just rests against the LCD screen Whatever you do, don’t try attaching anything with rubber suckers to an LCD screen, as you will completely ruin the surface of the display! My personal preference is the Gretag Macbeth Eye-One system, which is available in several different packages The Eye-One Photo measuring device is an emissive spectrophotometer that can measure all types of displays and build printer profi les as well when used in conjunction with the Profi leMaker 5 or Eye-One Match 3.0 software The Eye-One Display 2 device is a low cost colorimeter device and is designed for measuring both CRT and LCD displays If all you are interested in is calibrating and profi ling a computer display, there is no great

advantage in choosing a spectrophotometer over the more economically priced colorimeter devices But whatever you

do, I do advise you to include a calibrator/software package with any display purchase

Do you want good color or just OK color?

Let me summarize in a few paragraphs why you should pay special attention to how your images are displayed in Photoshop and why good color management is essential

The choice of an LCD or CRT display can be a matter

of individual choice Although Sony, Eizo, Viewsonic, Phillips and NEC still appear to be selling CRTs, I have

a personal preference for using LCDs Once you have chosen a good display you need to consider how you are

Color managing the print output

This leaves the question of how to profi le

the print output Well, getting custom

profi les built for your printer is a good

idea, and this topic is covered in some

detail in Chapter 12 However, calibrating

and building a profi le for your display

is by far the most important step in the

whole color management process Get this

right and the canned profi les that came

with your printer should work just fi ne

You should already be seeing a much

closer match between what you see on the

display and what you see coming out of

your printer But without doubt, a custom

print profi le will help you get even better

results

going to calibrate and fi ne-tune it This is crucial and if it

is done right it will mean you can trust the colors you see

on the screen You are going to be spending a lot of time looking at the display as you work in Photoshop and you will naturally want to see print results that match what you saw on the screen In the long run you are going to save yourself an awful lot of time and frustration if you calibrate and profi le the screen properly from the start

Not so long ago, the cost of a large screen, plus a decent video card, would have cost a small fortune and monitor display calibrators were specialist items These days, a basic monitor calibration and profi ling device can cost about the same as an external hard drive, so I would urge anyone setting up a computer system for Photoshop to put a monitor display calibrator high on their spending list A standard colorimeter like the Eye-One Display 2 from Gretag MacBeth is easy to set up and use and all the necessary software will be supplied to enable you to calibrate and build a profi le for your monitor

All the monitor display calibrator products I have tested will automatically place a profi le for your monitor in the correct folder in your system and you are then ready to start working straight away in Photoshop with a properly calibrated display Once you are in Photoshop you need to make sure you are using the right color settings for your workfl ow: see page 110 for instructions on how to check

if you are using the right settings for a photography setup

Once that is done, the Color Settings will remain set until you change them And after that, all you need to worry about is making sure that the calibration and profi ling for your display is kept up to date If you are using a CRT type display, this should probably be done about once a week

If you are using an LCD type display, the profi ling is just

as important, but regular calibration will not be quite so critical Checking once a month will probably be enough

Color management does not have to be intimidatingly complex and nor does it have to be expensive So the question is, do you want good color or simply OK color?

Or, to put it another way, can you afford not to?

Gamma setup

When you utilize a calibration device the calibrating software will want to ask you which gamma you will be using Now quite often you are told that PC users should use

a 2.2 gamma and Macintosh users should use a 1.8 gamma But a 2.2 gamma is the ideal gamma setting to use regardless of whether you are on a Mac or a PC You can build a correct monitor profi le using

a 1.8 gamma option, but 2.2 is closer to the native gamma of most displays I once asked an engineer why they still included

it as an option in their software and he replied that it’s only there to comfort Mac users who have traditionally been taught to use 1.8 So now you know

Display luminance

The target luminance will vary according which type of display you are using A typical modern LCD display will have a luminance of 200 candelas M2 or more at the maximum luminance setting, which

is way too bright for image editing work

in subdued offi ce lighting conditions

And with older CRT monitors you may be lucky to reach the desired target of 100 candelas M2 (a sure sign that the display

is due for retirement) A target of around

140 candelas M2 is ideal for a desktop LCD monitor display

Calibration using a third-party calibrator

The following steps show an example of how to use the Eye-One Match 3.0 software with a Gretag MacBeth monitor calibration device

White point setup

The other puzzling question concerns the

white point You will sometimes be urged

to choose a 5000 K whitepoint for print

work My advice is to always use 6500 K

instead Most displays run naturally at

a white point of 6500 K Some people

regard 5000 K as being the correct value

to use for CMYK proofi ng work But in

reality, the whites on your display will

appear too yellow at this setting 6500 K

may be cooler than the assumed 5000 K

standard, but 6500 K will give much better

contrast on your display and your eyes

always adjust naturally to the colors

on the display, the same way as your

eyes adjust normally to fl uctuations in

everyday lighting conditions The apparent

disparity of using one white point for the

lightbox and another for the display is not

something you should worry about

With LCD displays it is not possible

to physically adjust the whitepoint, so it

is better to select the native white point

option when calibrating an LCD display

Again, remember that colors are perceived

relative to the white point and the eye will

compensate naturally from the white point

seen on the display to the white point used

by an alternative viewing light source

1 I like using Eye-One Match 3 because it is easy to set up and use The initial

screens will ask what type of device you which to profi le In this case, I wanted to calibrate and profi le an LCD display I set the white point to Native, the Gamma

to 2.2 and the luminance to 140 candelas M 2 , the recommended target setting for desktop LCD displays.

2 Eye-One Match will then ask you to calibrate the device (placing it on the base

unit to measure the white tile) before hanging the device onto the screen.

3 You will then be asked to set the contrast to maximum (skip this step if

calibrating an LCD) and then adjust the brightness, by starting with the brightness controls dimmed right down Eye-One Match will measure the display as you gradually increase the brightness and indicate when you have reached the target luminance setting you set at the beginning.

4 When you proceed to the next step, Eye-One Match will automatically sense the

placement position of the calibration device and start measuring a sequence of colors from the display and, once it has completed doing this, generate a monitor profi le named with today’s date All you have to do is click OK to establish this as the new monitor profi le to use, replacing any previous monitor profi le You might also want to set a reminder for when the next monitor profi le should be made If you are using an LCD, once every 4 weeks should be just fi ne.

Old monitor profi les

Do you really need to hang on to old monitor profi les? I recommend that you purge the Colorsync Profi les folder on your system of older monitor profi les to avoid confusion All you really need is one good up-to-date profi le for your display

Color management settings

One of the very fi rst things you should do after installing Photoshop is to confi gure the color management settings

The default Photoshop color settings are confi gured using

a general setting for the region you live in, which will be: North America, Europe or Japan If you are using Photoshop for design work or photography, you will want

to follow the prompt that Photoshop is giving you here Go

to the Edit menu and select Color Settings This will open the dialog shown in Figure 3.4 Next, go to the Settings menu and select one of the prepress settings The individual prepress settings only differ in the default RGB to CMYK conversions that they use, and which you should choose will depend on the geographical area you are working in

So if you live and work in the US, choose North America Prepress 2 and you will be fi ne with that setting Please note that adjusting the prepress settings will change the RGB working space from sRGB to Adobe RGB This is a good thing to do if you intend editing RGB photographs

in Photoshop But it is not enough just to change the RGB workspace setting on its own The prepress settings

Figure 3.4 The Photoshop Color Settings All the Photoshop color settings can be

managed from within this single dialog.

Synchronizing the Color Settings

I recommend people look at the region

settings and if these do not suit exactly,

then make the necessary changes and

save these as a custom user setting Once

this is done, open Bridge (if you have

not done so already and synchronize the

Color Settings there) If you are using

other programs in the Creative Suite this

will ensure that the same color settings

are used in all the other programs, such as

InDesign Finding this later can be a real

problem, and is so easy to avoid

will also adjust the policy settings to preserve embedded profi les and ignore profi le mismatch warnings This will minimize the number of times you are shown the profi le mismatch warning dialog when working with image fi les that are in different color spaces.

You don’t need to worry too much more about the ins and outs of Photoshop color management just yet, but as your Photoshop knowledge increases you will defi nitely want to read in more detail about the color management system in Chapter 12 and also Chapter 13 on how to print output

Extras

An internal 24× or faster CD-ROM drive is standard issue these days Other things to buy could include a second hard drive to use as a scratch disk plus a removable media storage device such as the Iomega Zip drive or a CD writer, although a lot of computers are sold with a CD drive that functions as a CD writer and DVD writer too You need these to back up your main hard disk and store all your image documents It is tempting to accumulate lots of image fi les on the computer hard drive, but you have to ask yourself what would happen if your computer got stolen or that hard drive failed Removable disks are ideal for transferring documents off-site Print shops should

be able to satisfactorily read Mac and PC format fi les whether supplied on ZIP, CD or DVD USB 2 and FireWire

800 (IEEE 1394) are the latest connection standards for peripheral devices You can have up to 127 USB devices linked to a single computer and you can plug and unplug USB devices while the machine is switched on USB 2 is the latest standard and has many advantages for those in

a PC working environment USB 1.0 is slow, but it’s fi ne for connecting control devices such as the mouse, Wacom tablet and printer FireWire has the potential to provide fast data transfer rates of 100 MB+ per second (faster still with FireWire 800) So use FireWire wherever possible to connect devices that rely on fast data transfer such as hard drives, CD writers, digital cameras and scanners

Figure 3.5 Wacom™ pad and pen.

Graphics tablets

I highly recommend you get a digitizing graphics tablet This is pressure responsive and is easier to draw with and can be used alongside the mouse as an input device Bigger is not necessarily better Some people like using the A4 sized tablets, others fi nd it easier to work with an A5 or A6 tablet from the Wacom™

Intuos™ range, which now features a cordless mouse and switchable pens

You don’t have to move the pen around

so much with smaller pads and these are therefore easier to use for painting and drawing Once you have experienced working with a pen, using the mouse will seem like trying to draw while wearing boxing gloves! The ™ Cintiq™device is a combination of LCD monitor and digitizing pen pad This radical new design will potentially introduce a whole new concept

to the way we interact with the on-screen image I don’t know if it is going to be generally seen as the ideal way of working with photographs, but there are those who reckon it makes painting and drawing a more fl uid experience

Backing up image data

The solution I use is to archive important data on primary and backup hard drives and maintain a further backup archive using DVD disks The cost of hard disk storage space is so cheap that this is now an easily affordable solution It means I can access important fi les more easily while I am working on the computer, and I am using the one method of disk storage which has so far remained relatively unchanged over the years and therefore has more chance of continuing to be supported in the future For

a basic studio setup I would recommend storing all your archive images and work in progress images on an external drive and carry out scheduled backups to a secondary hard drive of matching size that can be stored off-site or kept in

a fi re proof safe

For extra backup, I like to archive my fi les to removable media In the lifetime of the Photoshop program we have seen many different systems come and go Floppies, Syquests, Magneto Opticals the list goes on And although you can still obtain devices capable of reading these media formats, the question is, for how long? And what will you do in the future if a specifi c hardware device fails to work? The introduction of recordable CD/DVD media has provided a reasonably consistent means of storage since, for at least 10 years now, nearly all computers have been able to read CD and DVD discs

DVD drives have evolved to provide much faster read/write speeds DVD media may be able to offer increased storage space in the future, and we are already seeing bigger disc media storage systems such as Blu-ray Disc and HD-DVD

So how long will CD and DVD media remain popular and

be supported by future computer hardware? More to the point, how long will the media discs themselves last? It

is estimated that aluminium and gold CD discs could last

up to 30 years, or longer, if stored carefully in the right conditions such as at the right temperature and away from direct sunlight DVD discs that use vegetable dyes may have an even shorter life-span

Backup strategies

For a more detailed look at how to back up

your fi les, please refer to Chapter 11 on

image management

Photoshop preferences

The Photoshop preferences are located in the Edit menu

in Windows and the Photoshop menu in OS X The preferences let you customize the various Photoshop functions A new preference fi le is generated each time you exit Photoshop and deleting or removing this fi le will always force Photoshop to reset all its preferences The preference fi le is stored along with other program settings

in the system level Preferences folder (Mac) or Registry folder (PC): C:/Documents and Settings/Current User/

Application Data/Adobe/Photoshop/10.0/Adobe Photoshop CS3 Settings

General preferences

When you open the preferences you will fi rst be shown the General preferences I suggest you leave the Color Picker set to Adobe (unless you have a strong attachment to the system Color Picker) And leave the image interpolation set

to Bicubic If you need to override this setting then you can

do so in the Image ➯ Image Size dialog

The Automatically Launch Bridge option will ensure Bridge is always launched in the background and ready for immediate use Check Auto-Update Open Documents

Resetting the preferences

If you hold down COSLAS during startup cycle, this will pop a dialog box that allows you to delete the current Photoshop preference fi le

Figure 3.6 The General preferences dialog.

Resetting dialogs

The Reset All Warning Dialogs will reset things like the profi le mismatch warning messages These dialogs contain a Don’t Warn Me Again checkbox – if you had pressed any of these at any time, and wished to restore them, click here The Reset All Tools in the Options bar will reset the tool behavior

Back up the preference fi le

After setting up the preferences, create

a duplicate of the Photoshop preference

fi le and store it within easy reach Having access to a clean preference fi le can speed resetting the Photoshop settings should the working preference fi le become corrupted

if you are share fi les that are open in Photoshop but have been updated by another application Only check the Beep When Done box if you want Photoshop to signal a sound alert when tasks are complete The Dynamic Color Sliders option ensures that the colors change in the Color palette as you drag the sliders, so keep this selected

Unchecking the Export Clipboard box will save time when you exit Photoshop to launch another program, but

if you really need the ability to paste clipboard contents to another program then leave it on, but otherwise I suggest you switch it off The Use Shift Key for Tool Switch answers the needs of users who wish to disable the Shift key modifi er for switching tools in the Tools palette with repeated keyboard strokes The Resize Image During Paste/Place is useful if you want pasted or placed items

to be automatically scaled to match the size of the image you are pasting/placing them in Check the Keyboard Zoom Resizes Windows if you want the image window to shrink to fi t whenever you use a keyboard zoom shortcut like C-L- or C+L+ And lastly, there is the Zoom Scroll Wheel option which among other things will enable you to zoom in and out via the scroll wheel

if you have one on your mouse Holding down S will constrain the zoom to the usual percentage increments

The History log is useful if you wish to keep track of everything that has been done to an image The History Log options will let you save the history log directly in the image fi le metadata, to a saved text fi le stored in a pre-confi gured folder location, or both The edit log items can

be recorded in three modes Sessions will record which fi les are opened and closed and when The Concise mode will record an abbreviated list of which tools or commands were applied, again with times Both these modes can provide basic feedback that could be useful in a studio environment

to monitor time spent on a particular project and calculate billing The Detailed mode records everything, such as the coordinates used to make a crop This mode can be useful, for example, in forensic work

Customizing the UI Font Size

LCD computer displays are getting bigger

all the time and are only really designed to

operate at their best when using the fi nest

resolution setting This can be great for

viewing photographs, but the downside is

that the application menu items are getting

smaller and smaller The UI (user interface)

Font Size option allows you to customize

the size of the smaller font menu items

in Photoshop so that you don’t have to

strain your eyes too hard to read them For

example, when using a large LCD screen,

the Medium font size option will make it

easier to read the smaller font menu items

from a distance

Figure 3.7 Interface preferences.

Interface

Regarding what I said earlier about removing distracting colors from the interface, the Use Grayscale Toolbar Icon option will remove the blue color from the Photoshop icon in the Tools palette The Display Color Channels in Color option is a somewhat redundant feature as this does not really help you visualize the channels any better If anything it is a distraction and is best left unchecked

Photoshop allows you to create custom menu settings and use colors to highlight favorite items, but this feature aspect can be disabled by unchecking the Show Menu Colors item When the Show Tool Tips option is checked you will see tool tips displayed a few seconds after you roll over most items in the Photoshop interface Tool tips are an excellent learning tool, but can become irritating after a while The Auto-Collapse Icon Palettes option will allow you to open palettes from Icon mode and auto collapse them back to Icon mode again as soon as you start editing the image And if you would like Photoshop to always remember the last used palette layout, check the Remember Palette Locations box (the Reset Palette Locations to Default option is also located under the Window menu, as are the saved Workspace settings)

File Handling

You will normally want to include image previews when you save a fi le It is certainly useful to have image thumbnail previews that are viewable in the system dialog boxes although the Bridge program is capable

of generating large thumbnails regardless of whether a preview is present or not You can also choose to save

a Windows and Macintosh thumbnail with your fi le, to enable better cross-platform compatibility Appending a

fi le with a fi le extension is handy for keeping tabs on which format a document was saved in and is also very necessary when saving JPEG and GIF web graphics that need to be recognized in an HTML page If you are exporting for the Web, you may want to check the Use Lower Case box for appending fi les But instances of where servers trip up on upper case naming are fairly rare these days

File compatibility

Now that Camera Raw is able to edit JPEG images as well

as raw fi les, you can set a preference to automatically open Camera Raw every time you open a JPEG image This is only useful if you shoot in JPEG mode and wish to use Camera Raw to process the JPEG masters without actually editing the master fi les (because Camera Raw records all the edits as separate instructions) And you can set a preference to always launch Adobe Camera Raw as your favored raw processor when opening a proprietary raw

fi le Some cameras may embed an sRGB profi le tag in the EXIF metadata of a JPEG capture fi le, where the image profi le isn’t actually a correct sRGB profi le If you check the Ignore EXIF profi le tag, Photoshop will ignore this particular part of the metadata and read from the embedded profi le data instead

A TIFF format fi le saved in Photoshop 6.0 or later can contain all types of Photoshop layer information and a

fl attened composite is always saved in a TIFF If you place

a layered TIFF image in a page layout, only the fl attened composite will be read by the program when the page is

fi nally converted to print Some people argue that there

Economical web saves

There are times though when you don’t

need previews Web graphic fi les should

be uploaded as small as possible without

a thumbnail or platform specifi c header

information (Save for Web defaults to

removing previews) I usually upload

fi les to my server in a raw binary format,

which strips out the previews and other fi le

resource information anyway

Restart to activate preferences

Some of the Photoshop preferences will

only take effect after you quit and restart

the program For example, the Scratch Disk

preference settings will only come into

effect after a restart, and the same is true of

other preferences such as the Prefer Adobe

Camera Raw for JPEG fi les preference

setting

are specifi c instances where a layered TIFF might trip up

a print production workfl ow, so it might be safer to never save layers in a TIFF if you don’t know for certain where your fi les will be printed When the Ask Before Saving Layered TIFF Files option is checked, Photoshop will present you with an option to either fl atten or preserve the layers when saving a layered image as a TIFF If this is unchecked, then the layer information will always be saved with a composite and there will be no warning dialog

However, standard Photoshop PSD fi les created in Photoshop CS3 are never going to be 100% compatible

if they are likely to be read by someone using an earlier version of Photoshop This has always been the case with every upgrade of the program Setting the Maximize PSD and PSB Compatibility to ‘Always’ will allow you to do the same thing as when saving a fl attened composite with

a TIFF This option will ensure that a fl attened version of the image is included with the saved Photoshop fi le and the safe option is to always keep this checked For example, if you create a Smart Object layer in Photoshop CS2 or CS3, the Photoshop fi le will not be interpreted correctly when read by Photoshop CS or earlier, unless you maximize the compatibility of the saved PSD In these circumstances, if

Figure 3.8 The File Handling preferences.

Version Cue

The Enable Version Cue Workgroup File Management relates to the use of Adobe Version Cue This option caters for those working in a networked environment and where they are sharing working on image

fi les with other Photoshop users When a user ‘checks out’ a fi le, only he or she can edit it The other users who are sharing your

fi les will only be able to make edit changes after the fi le has been checked back in This precautionary fi le management system means that other users cannot overwrite your work while it is being edited

Photoshop is unable to interpret an image, it will present

an alert dialog This will warn that certain elements cannot be read and offer the option to discard these and continue, or to read the composite image data Discarding the unreadable data will allow another user to open your image, but when opened, it will be missing all the elements you added and most likely look very different from the

fi le you intended that person to receive But if they click the Read Composite Data button, and a composite was saved, the image will open using a fl attened composite layer which does look the same as the image you created and saved If no composite was created, they will just see a white picture and a multi-language message saying that no composite data was available

Adobe InDesign allows you to place Photoshop format (PSD) fi les in a page layout but, if you do so, the Maximize Backwards Compatibility option must be checked in the General preferences (to generate a fl attened composite)

If you use layered TIFF, PSD (or Photoshop PDF) format

fi les in your page layout workfl ow, you can modify the layers in Photoshop and the page design image will immediately be updated This way you don’t run the risk

of losing synchronization between the master image that

is used for Photoshop edits and a fl attened version of the same image that is used solely for placing in the layout

If you want to ‘round trip’ your images this way, TIFF is the more universally recognized fi le format

The downside is that you may end up with bloated fi les and these can signifi cantly increase the fi le transmission times If you are archiving layered Photoshop images, the most effi cient option could be to save using the native PSD format and have Maximize PSD File Compatibility set to ‘Never’ But such economies can come at a price

Maximizing PSD compatibility will make image load quicker in Bridge (and other fi le browser programs) and Adobe Lightroom is only able to read layered PSD

fi les that have this option turned on If there is no saved composite, Lightroom won’t be able to import it

Recent File list

The Recent File list refers to the number

of image document locations remembered

in the Photoshop File ➯Open Recent

submenu I usually like to set this number

to remember the last 10 opened images

But you may wish to set this higher

Performance

The Performance preferences section lets you confi gure all the things in Photoshop that will infl uence how effi ciently Photoshop is able to run on your computer The memory usage can now be set using a sliding percentage scale and you will notice how Photoshop provides a hint as to what the ideal range should be for your particular computer The History & Cache preferences are now placed here too The default number of History States is 20 You can set this to any number you like from 1–1000, but remember that the number of histories you choose will have a bearing on the scratch disk usage The image cache settings affect the speed of screen redraws Setting a higher number can help

if you often work with very large images in Photoshop

In the Scratch Disks section you can nominate up to four hard drives as scratch disks Note how you now get to see more information about each disk used and can drag

to rearrange them in order of priority (I’ll be discussing memory and scratch disk usage over the next few pages)

Checking the Enable 3D Acceleration option in the GPU Settings will allow Photoshop to make full use of the graphics processor memory on GPU enabled graphics cards

Figure 3.9 The Performance preferences, where you can confi gure the Memory

usage, History, Cache, Scratch Disks and GPU settings.

In many instances this should lead to an improvement in graphics performance, but cannot be guaranteed This is because with some of the more recent computers, or soon to be released Intel chip computers, the Central Processor (CPU) may actually offer the fastest graphics performance

RAM memory and scratch disks

The amount of RAM memory you have installed is a key factor that will determine how effi ciently you can work

in Photoshop Adobe recommend for Photoshop CS3 that you allocate a minimum of 320 MB RAM memory, which means that if you allow an additional 128–256 MB of RAM for the operating system, you will need to have at least 512 MB of RAM installed in your computer If you also take into account the requirements of other programs and the likelihood of newer operating systems needing even more memory, it is perhaps safer to suggest you will need a minimum of 1GB RAM memory in total

Each time you launch Photoshop a certain amount of RAM memory will be set aside for use by the application, and this will depend on the amount set in the Performance preferences as a percentage of the total amount of RAM that is available to Photoshop The fi gure you see in the Performance preferences is the RAM reserved for Photoshop imaging use, although the RAM you set aside for Photoshop will be shared by other applications when it

is not actively being used by Photoshop, and don’t forget that you will need to allow RAM memory to run Adobe Bridge at the same time as Photoshop

How much RAM is available to Photoshop will depend

on the total amount of RAM memory installed Photoshop CS3 is a 32-bit application that is designed to work on computers with 32-bit or 64-bit processors running 32-bit

or 64-bit operating systems If you run Photoshop on a 64-bit computer that has 4 GB or more of RAM installed,

a maximum of 3 GB will be allocated to Photoshop for handling image data When you go to the Performance preferences, the total available RAM will be displayed in the Memory Usage section and below this you will see the recommended percentage of memory to allocate to Photoshop On a Windows system the default setting is 50% and on a Mac it will be 70% Although the memory assigned to Photoshop is freed up whenever Photoshop is not running, if the memory is set too high Photoshop may end up competing with the operating system for memory and this will slow performance

Virtual memory tricks

The Apple Macintosh and Windows

operating systems are able to make

effi cient use of memory using their own

virtual memory management systems

The Windows VM fi le should be set to at

least 1.5 times your physical memory size

There are some software utilities that claim

to double your RAM, but these will confl ict

with Photoshop’s virtual memory and

should not be used

Move don’t copy

To copy selections and layers between

documents, use drag and drop actions with

the move tool This will save on memory

usage and at the same time preserve the

current clipboard contents

RAM memory upgrades

Most PCs and Macs use DIMMs (Dual

In-line Memory Modules) The specifi c

RAM memory chips may vary for each type

of computer, so check carefully with the

vendor that you are buying the right type

for your machine RAM memory used to

cost a small fortune, but these days the

price of RAM is almost inconsequential If

you have four RAM slots on your machine,

you should easily be able to install 4 × 512

MB RAM or 4 × 1 GB RAM memory chips,

which will give you 2 or 4 GB of installed

RAM

Speed and effi ciency test

To help evaluate the performance effi ciency of your computer setup, there

is a really useful weblink to a site hosted

by a company called Retouchartists.com:

retouchartists.com/pages/speedtest.html

From there you can download a test fi le which contains a sample image and a Photoshop action that was created by Alex Godden All you have to do is time how long it takes for the action to complete,

to gauge and compare how fast your computer is running And then you can compare your speed test results with others

Enhancing memory and performance

The Performance preferences will provide a guide for the ideal RAM setting for your computer and what the upper limit should be, but you can always try allocating 5% above the recommended amount of memory, relaunch Photoshop and closely observe the Effi ciency readout in the status bar or Info palette Monitor the Effi ciency readout:

anything less than 100% will indicate that Photoshop is running short of RAM memory and having to make use

of extra scratch disk space But if you allocate too high a percentage, this will also compromise effi ciency The trick

is to fi nd the optimum percentage before you see a drop in performance You might fi nd the speed test described in the sidebar is a useful tool for gauging Photoshop performance

If you have more than 4 GB memory installed (up to

6 GB on Windows and 8 GB on Mac OS X), the RAM above 4 GB can also be used by the operating system as

a cache for the Photoshop scratch data So although you can’t allocate this extra memory directly, installing extra memory can boost Photoshop’s performance

Photoshop stores data such as recent history states and clipboard data in its memory on the scratch disk

Copying a large selection to the clipboard also uses up a lot of the scratch disk memory Should you experience a temporary slowdown in performance you might want to purge Photoshop of any excess temporarily held data in the memory To do this, choose Edit ➯ Purge ➯ Undo, Clipboard, Histories or All

Scratch disks

Photoshop utilizes free hard disk space as an extension of RAM memory and makes use of all the available free hard disk as specifi ed in the Scratch Disks section as ‘ virtual memory’ When you launch Photoshop it will check to see how much hard disk space is free for scratch disk usage and it is worth noting here that should you for any reason have less scratch disk space than RAM memory space, the RAM memory will be restricted by the amount of scratch disk space that is available

The primary scratch disk should ideally be one that

is separate to the disk running the operating system and Photoshop If you partition the main disk volume and designate an empty partition as the scratch disk, this will serve no useful purpose because the disk drive head will simply be switching back and forth between different sectors of the same disk as it tries to do the job of running the computer system and providing scratch disk space For optimal image editing, at least 4 GB of free hard disk space

is recommended, but ideally you want a scratch disk with

at least 20–40 GB of free space, and the disk used should

be as free as possible of fragmentation

Photoshop always makes the most effi cient use of real RAM memory and tries to keep as much RAM as possible free for memory intensive calculations Low-level data like the ‘last saved’ version of the image is stored in the scratch disk memory giving priority to the current version and last undo versions being held in RAM Normally, Photoshop uses all the available free RAM as buffer memory in which

to perform real-time calculations and mirrors the RAM memory contents on the scratch disk Photoshop does this whenever there is a convenient opportunity to do so For example, after you open a new image you may notice some disk activity as Photoshop writes from the RAM memory buffer to the scratch disk Photoshop then continually looks for ways to economize the use of RAM memory, writing to the hard disk in the background whenever there are periods

of inactivity Scratch disk data is also compressed when

it is not in use (unless the optional plug-in extension that prevents this has been loaded at startup)

When Photoshop exhausts its reserves of RAM memory, it is forced to use the extra space on the scratch disk as a source of virtual memory and this is where you often start to see a major slowdown in effi ciency When the Effi ciency indicator drops below 100% this means that the RAM buffer is full and Photoshop is now relying exclusively on the hard disk scratch disk space as a memory reserve

Scratch disk usage and history

The scratch disk usage will vary according

to how many history states you have set

in the History and Cache section and

also how you use Photoshop Generally

speaking, Photoshop will store a version of

each history state, but it does not always

store a complete version of the image

for each history state As was explained

in Chapter 2, the History feature only

needs to save the changes made in each

image tile So if you carry out a series of

brush strokes, the history will only store

changes made to the altered image tiles

For these reasons the scratch disk usage

will increase as you add more history

states, but in practice the usage does not

increase in large chunks, unless you were

to perform a series of global fi lter changes

Figure 3.10 You can monitor how effi ciently

Photoshop is running by adjusting the Info

palette options to display an Effi ciency readout

If the effi ciency reading drops below 100% this

means that Photoshop is having to rely on the

designated scratch disk as a virtual memory

source.

Scratch disk performance

With all this reliance on the scratch disk (or multiple scratch disks) to read/write data from the RAM memory buffer, the hard disk performance of the scratch disk plays

an important role in maintaining Photoshop effi ciency

There is provision in Photoshop for as many as four scratch disks Each individual scratch fi le created by Photoshop can be a maximum of 2 GB and Photoshop can keep writing scratch fi les to a scratch disk volume until it becomes full When the primary scratch disk runs out of room to accommodate all the scratch fi les during a Photoshop session, it will then start writing scratch fi les to the secondary scratch disk and so on This makes for more effi cient and faster disk usage

Interface connections

Most modern Macs and PCs have IDE, ATA or SATA drives as standard A fast internal hard disk is adequate for getting started But for better performance results, you should really install a second internal or external hard drive and have this dedicated as the primary scratch disk (make this the number one scratch disk in the Performance preferences) Your computer will most likely have the choice of a USB or FireWire connector for linking external devices USB 2 offers a much faster connection speed than the old USB 1 FireWire (IEEE 1394) has many advantages over the older SCSI interface First of all FireWire is

a lot faster and secondly, it will often allow you to hot swap a drive between one computer and another This is particularly useful when you wish to shuttle very large fi les around quickly With the advent of FireWire 800 we are now seeing an appreciable improvement in data transfer speeds FireWire drives are still IDE drives with a bridge to the FireWire standard, and since the Oxford Chipset came out, they have been able to enhance the throughput closer

to the theoretical limit Internal SCSI connections often use SCSI 2, which provides a quicker data transfer standard

Note that it is the data transfer and not data access time that

is the measure of disk speed to look out for

Assigning scratch disks at startup

If you keep the COLAkeys held down at the beginning of the Photoshop startup cycle, you can fi rst choose the location of the Additional Plug-ins Folder, followed by a prompt to assign the scratch disks

Hard drive spindle speeds

Most desktop computers use internal drives which run at 7200 rpm and you can easily fi nd spare internal drives that run

at this speed or faster There are drives that even run at 10,000 rpm, but these are hard to come by and expensive Laptop computers usually have slower hard drives

fi tted as standard (typically 5400 rpm) If you are working regularly from a laptop, you should notice quite a difference if you use just a standard external drive running

at 7200 rpm as the primary scratch disk

Oxford Chipset

The most common Oxford Chipset is the

911, but 924 is even faster, and can be found in the very reliable Wiebetch drives

RAID scratch disks

A striped RAID disk setup will offer the fastest scratch disk option RAID stands for Redundant Array of Independent Disks A simple way to explain RAID is that it allows you

to treat multiple drives as a single drive volume to provide either increased data integrity, capacity, transfer rates or fault-tolerance compared to a single volume And how

it does this depends on the RAID level you choose You will need a minimum of two disks to confi gure a RAID system and most off-the-shelf RAID solutions are sold

as a bay dock that can accommodate two or more drives with a built-in RAID controller A RAID disk can usually

be connected via internal SCSI or an external FireWire 400/800 connection

RAID 0 (striping)

With a RAID 0 setup, two or more drives are striped together to create a single large volume drive So for example, if two 200 GB drives are striped using a RAID 0 setup you will end up with a single 400 GB volume RAID

0 is useful where you require fast hard drive access speeds, because the drive access speed will increase proportionally

to the number of drives that are added So if you have a 2 x

200 GB drive RAID 0 system, the hard drive access speed should be two times that of a single 400 GB drive This is why a RAID 0 setup is ideal for Photoshop scratch disks

Internal RAID

You can fi t an internal RAID system with a do-it-yourself kit consisting of two internally mounted drives and a RAID controller card It should not be too challenging to install yourself, but if you are in any doubt about whether you are capable of doing this then you should get a qualifi ed computer specialist to install the system in your computer

The advantage of an internal RAID is that it is always there whenever you turn the computer on and is an economical solution compared to buying an external RAID drive setup

Most PC tower computer systems should have plenty of free hard drive bays, which will make it fairly easy for

Software RAIDs

It used to be the case that software-created

RAIDs such as the one included with the

Mac OS X Disk Utilities program were a

lot slower than a dedicated system The

read/write speeds from a software RAID

will still be slower than a true dedicated

RAID system since a software RAID will be

stealing some of your computer processor

cycles, but these days the speed loss is not

so bad as it used to be A software-driven

internal striped RAID 0 can bring about

a 45% increase in disk access speed

Overall I recommend that if you do choose

to go down the internal RAID route, you

include a RAID controller

Figure 3.11 A RAID system drive setup

contains two or more drives linked together that can provide either faster disk access or more secure data backup.

you to install internal RAID The older G4 Macintosh computers will allow you to fi t two extra drives to form

a striped RAID 0 which can be managed by an internally mounted PCI slot controller card Note that the latest G5 desktops only have room to fi t one extra drive So a Quad G5 computer will only suit an internal mirrored RAID

1 or a striped RAID 0 setup, which is not much use for Photoshop work But if you get one of the WiebeTECH G5 Jam Plus kits, this will allow you to install up to four extra drives and includes a RAID controller card

A RAID setup will defi nitely speed up the time it takes Photoshop to read and write data to the scratch disk However, if you have more hard drives running simultaneously this will mean more power consumption, which in turn will generate more heat and possibly more noise too The extra heat may cause problems for the cooling system in your computer and may put extra strain

on the internal power supply unit

External RAID

External RAID hard drive units are not overly expensive and you can easily buy a ready assembled bay dock with a couple of drives and a built-in RAID controller hardware that can be confi gured for RAID 0 The speed will be governed not just by the number of drives making up the RAID but also by the speed of the cable connection Some RAID systems still use wide SCSI and require a SCSI card

to connect to the computer More often these days they will connect via Firewire 400/800 or SATA, which may again require a special card in order to connect to the computer (for now) Computers in the future are more likely to support SATA as standard

Image Cache

The image cache settings affect the speed of screen redraws Whenever you are working with a large image, Photoshop uses a pyramid type structure of lower resolution cached versions of the full resolution picture

Each cached image is a quarter scale version of the previous cache level and is temporarily stored in memory

to provide speedier screen previews Basically, if you are viewing a large image on screen in ‘Fit to screen’ display mode, Photoshop will use a cache level that is closest to the fi t to screen resolution to provide a screen refresh view

of any edit changes you make at this viewing scale The cached screen previews can provide you with faster screen redraws and larger images will therefore benefi t from using

a higher cache level A higher setting will provide a faster screen redraw, but at the expense of sacrifi cing the quality

of the preview This is because a lower resolution cache preview is not as accurate as choosing to view the image at Actual Pixels

Cache pyramid structure

You may sometimes notice how the layered Photoshop image on screen is not completely accurate at anything other than the 100% magnifi cation – this is the image cache at work, it is speeding up the display preview at the expense of accuracy If you have to work on an image at

a less than 100% magnifi cation, then do make sure the magnifi cation is a wholly divisible number of 100% In other words, it is better to work at 50%, 25% or 12.5%

magnifi cation, rather than at 66% or 33% Note also that the number of cache levels chosen here will affect the structure of a ‘Save Image Pyramid’ TIFF fi le

Cursors

The painting cursor can be displayed as a painting tool icon, a precise crosshair or with the default setting, which

is an outline of the brush shape at its ‘most opaque’ size

in relation to the image magnifi cation In Photoshop CS2 and CS3 you can choose to display a Full Size brush tip, representing the entire outer edge reach of a soft edged brush, although it is debatable whether this improves the appearance of the painting cursors or not

The Show Crosshair in Brush Tip option will allow you to additionally display a crosshair inside the brush size cursor

For Other Cursors, the Standard option will represent other tools using the tool icon I suggest you change this to the Precise setting, because this will make it easier for you to target the placement of these tools

The Ç key can be used to toggle the cursor display When the standard paint cursor is selected,

Ç will toggle between standard and precise

When the precise or brush size paint cursor option is selected, Ç will toggle between precise and brush size When standard cursor mode is selected for all other cursors, Ç will toggle between the standard and the precise cursor

Figure 3.13 The Display & Cursors preferences.

Figure 3.12 This is an example of the brush

cursor using the Full Size Brush Tip mode with Show Crosshair in Brush Tip.

Brush opacity and cursor size

When the Normal brush tip is selected, the brush cursor size will represent the boundary of the brush shape up to where the brush opacity is 50% or denser in opacity The full size cursor will represent the complete brush area size

Figure 3.14 The Transparency display settings are editable You have a choice

of Transparency display settings: None, Small, Medium or Large grid pattern, and a choice of different grid colors.

Transparency & Gamut

The Transparency settings determine how the transparent areas in an image are represented on the screen If a layer contains transparency and is viewed on its own with the background layer visibility switched off, the transparent areas are normally shown using a checkerboard pattern The display preferences let you decide how the checkerboard grid size and colors are displayed The Gamut Warning will alert you in advance to any colors that will be out of gamut after a conversion is made from, say, the RGB Color mode to whichever color space is currently loaded in the View ➯ Proof Setup menu So, if you are working on an image in RGB mode and you choose View

➯ Gamut Warning, Photoshop will highlight these gamut colors with a color overlay The gamut warning is, in

out-of-my view, a rather crude instrument for determining whether colors are in gamut or not, since a color that is only slightly out will be highlighted as strongly as a color that is hugely out of gamut A good quality graphics monitor using a Custom proof setup view mode is a much more reliable guide

Removing the checkerboard

I had an email recently from a reader

who wanted to know how to get rid of the

transparency checkerboard pattern If you

go to the preferences shown here you can

select different grid sizes and colors, but

you can also select None When None

is selected the transparent areas will be

displayed as solid white

Color Picker gamut warning

The Gamut warning can also be invoked

independently of the image in Photoshop’s

Color Picker dialog The default overlay

color is a neutral gray at 100% opacity,

but I suggest reducing the opacity to make

the gamut warning appear as a transparent

overlay

Units & Rulers

You can use this preference section to set the Ruler measurement (inches or centimeters, etc.) and type of units used The measurement units can also be changed via the Info palette submenu or by L right mouse-clicking a ruler to open the contextual menu You can also double-click the ruler bar as a shortcut for opening the preference window shown below The New Document Preset Resolution options allow you to decide what pixel resolution should be the default for screen display or print output work when you select a preset size from the File

➯ New Document dialog The Print Resolution setting is the more useful as this always has an important bearing on the size that an image will print The Screen Resolution has typically always been 72 ppi But there is no real signifi cance to whatever resolution is set here for an image that is destined to appear in a web page design Web browser programs are only concerned with the physical number of pixels an image has The resolution setting actually has no relevance

Figure 3.15 Ruler units can be set in pixels, inches, cm, mm, points, picas or as

a percentage The percentage setting is ideal for recording actions that you wish to apply proportionally at any image size.

Guides, Grid & Slices

These preferences let you choose the colors for the Guides, Smart Guides and Grid Both Grid and Guides can be displayed as solid or dashed lines, with the added option of dotted lines for the Grid The number of Grid subdivisions can be adjusted to suit whatever project you are working on and the Slice options include Line Color style and whether the Slice numbers are displayed or not

Figure 3.16 The Guides, Grid & Slices preferences.

Ensuring preferences are saved

Once you have confi gured your

preferences and got everything set up just

the way you want, it is a good idea to Quit

and restart Photoshop, as this will then

force Photoshop to save these preferences

to the preference fi le

Figure 3.17 The View ➯ Show menu options include Layer Edges When this

is selected the currently selected layer or layers will be indicated with a rectangular color edge border The Smart Guides option is useful as a visual aid for aligning layer elements The Smart Guides (shown here in pink) will fl ash on and off to indicate when a layer element is aligned to other layers in the image.

Accessing the JPEG 2000 plug-in

The JPEG 2000 fi le format plug-in is not installed as part of the regular Photoshop installation, but it will be installed in the Bridge Plug-ins folder So if you click the Additional Plug-ins Folder checkbox and click on the Choose button and navigate to the Bridge Plug-ins folder, you will be able

to save images out of Photoshop using the JPEG 2000 fi le format after you relaunch Photoshop

Plug-ins

The Plug-ins folder will automatically be recognized by Photoshop so long as it resides in the same application folder But you can also choose an Additional Plug-ins Folder that may be located in another application folder (such as Adobe Photoshop Elements) so these can in effect

be shared with Photoshop To do this click on the Choose

button to locate the additional folder If you install any third-party plug-ins that pre-date Photoshop CS3, they may possibly incorporate a hidden installation process that looks for a valid Photoshop serial number in the older style, consisting of letters and numbers To be honest, this change

in serial number formats happened such a long time ago,

it is unlikely you will need to bother with this But if you experience this type of problem, just remember that you can enter your old Photoshop serial number in the Legacy Serial Number box

If you keep the COLA keys held down at the beginning of the Photoshop startup cycle, this will pop a Navigation dialog that will let you point to the location of the Additional Plug-ins Folder

Figure 3.18 The Plug-ins preferences.

Type preferences

We could all do with smart quotes I guess, but the smart quotes referred to here are a preference for whether the text tool uses vertical quotation marks or rounded ones that are inverted at the beginning and end of a sentence The Show Asian Text Options is there for Asian users, to enable the Chinese, Japanese and Korean text options in the Character palette The Show Font Names in English option is of more signifi cance for non-English language users If they are using a regionalized version of Photoshop they will see an option for displaying font names in their native language

The Enable Missing Glyph Protection option will switch

on automatic font substitution for any missing glyph fonts (those swirly graphic font characters)

The Type tool Options palette also provides a WYSIWYG menu listing of all the available fonts when you mouse down on the Font Family menu (see Figure 3.19) The Font Preview Size menu will determine the font sizes used when displaying this list and this menu item should not be confused with the UI Font Size preference that is in the General preferences section

Figure 3.20 The Type preferences.

Figure 3.19 Photoshop presents the font lists

using a WYSIWYG menu listing.

T he aim of this chapter is to introduce you to the

basic Photoshop image adjustments Since this is what you are going to be doing to every picture you edit in Photoshop, it is worth spending some time understanding the underlying principles of what the adjustment tools do

When I fi rst started writing about Photoshop, one could assume that most images would have been brought

in from a scanner and had originated as rendered pixel images These days, a lot of photographers will be shooting digitally and therefore may be starting out with a raw capture fi le In this chapter I am going to focus on basic pixel image processing only and in the following chapter I will be showing you the alternative way to process camera capture images, using Camera Raw

Basic Pixel Image Editing

Chapter 4

Image capture and fi le output

All digital images will have been captured via a sensor of some kind If you use a fi lm scanner, the sensor device will pass across the surface of the fi lm or print to read the image and record the image capture data The scanner software will preview the capture data and allow you to make some basic adjustments before exporting it as a rendered pixel image A scanner will usually export such fi les as TIFF images

If you use a digital camera, the camera will record the light hitting the sensor and convert this into a digital capture fi le that can be processed in one of two ways If the camera is set to TIFF or JPEG mode, the camera will use an on-board processor (which is like a mini-computer)

to automatically calculate how best to interpret the raw capture data and render it as a fi xed TIFF or JPEG pixel image output If the camera is set to raw mode, it will instead save the unprocessed raw data as a raw output fi le and this will give you the fl exibility to make all the post-capture adjustments later and override the camera auto processing settings

The images you bring into Photoshop therefore fall into two categories Rendered pixel images are what most

of us are familiar with and these include: fi le outputs from

a scanner, images that have been captured digitally from

a camera using the TIFF or JPEG setting and, basically, any image that is not a raw fi le Such images can be opened directly into Photoshop and edited directly within the program The amount of editing that is required will depend on how well the images have been optimized But

in most cases you will need to use the adjustment tools described in this chapter to fi ne-tune your images, and the techniques discussed here should be regarded as essential foundation skills for Photoshop image editing Because, however, you bring your images into Photoshop, you will

at some point need to know how to work with the basic image editing tools like Levels and Curves, such as when adding adjustment layers to an image

Rendered pixels

In the main body text I refer to ‘rendered

pixels’ I use this to describe pixel images

after they have been converted from the

raw capture state This includes images

that are scanned as well as images that

have been captured with a digital camera

This is because all digital images are

captured using an analog sensor of some

kind The analog signal is processed to

form a raw digital image that can be saved

as a raw fi le or converted into a fi xed pixel

image by interpreting the raw data in a

specifi c way Once a capture image has

been rendered as a pixel image you cannot

revert to the raw data version unless you

have access to the raw data in a raw fi le

This is a key benefi t of shooting in raw

mode because preserving the raw capture

data as it comes off the camera will allow

you to interpret it in many different ways

before you fi x the raw data as a pixel

image

WYSIWYG image editing

If you want true WYSIWYG editing (what you see is what you get), it is important that you follow the instructions laid out in the previous chapter on how to calibrate the display and confi gure the color settings Do this and you will now be ready

to start editing your photographs with confi dence

In the case of raw images your choices are more open

You could use the raw processing software that came with the camera, or you could use one of the main independent raw processing programs such as Capture One from Phase One, Apple Aperture, Bibble or dcRaw But since this is a book about Photoshop I will be focusing later on how to use Adobe Camera Raw that is bundled with Photoshop CS3 This is the same raw processing engine that is used

by Adobe Photoshop Lightroom and the latest Camera Raw provides full compatibility with most of the develop settings in Lightroom

If you intend bringing your images in via Camera Raw,

it can be argued that the Photoshop image adjustment tools are unnecessary, because Camera Raw will provide you with all the tools you need to produce perfectly optimized images You can save Camera Raw adjustments to disk

or open Camera Raw processed images as rendered pixel images in Photoshop If you shoot digitally, I recommend you use the raw mode and suggest you carry out all the initial image editing in Camera Raw rather than in Photoshop, and would advise you to follow the instructions outlined in Chapter 5 for optimizing raw images However, you will still fi nd that the information contained in this chapter is important, because it will teach you how to use the basic editing tools These are the things that every Photoshop user should be aware of and need to use when applying things like localized corrections So, for now, let’s look at basic pixel image editing techniques

Scanner software

If you are scanning in images you will mostly be limited

to working with the software that was supplied with the scanner I recommend that you use the scanner software

to optimize the image to a minimum standard in which the levels are just about beginning to clip the shadows and highlights Some scanner software will allow you to add sharpening or noise reduction But you may prefer to bypass these built-in scanner controls, because you can also apply such corrections in Photoshop

Adobe Photoshop Lightroom

The Adobe Photoshop Lightroom program

is designed as a raw processor and image management program for photographers

As mentioned in the text, it uses the exact same Adobe Camera Raw color engine that

is used in Photoshop CS3, which means that raw fi les that have been adjusted in Lightroom can also be read and opened via Photoshop However, Lightroom has the advantage of offering a full range of workfl ow modules designed to let you edit and manage raw images all the way from the camera import stage through to print and web output

Digital camera histograms

Some digital cameras provide a histogram

display that enables you to check the

quality of what you have just shot This

too can be used as an indication of the

levels captured in a scene However, the

histogram you see displayed is often

based on a JPEG capture only If you

are shooting in JPEG mode, that’s what

you are going to get But if you prefer to

shoot using raw mode, the histogram will

not provide an accurate guide to the true

potential of the image you have captured

See Chapter 11 for more about digital

capture and shooting in raw mode

The image histogram

The histogram is a bar chart that graphically represents the shades of tone (described as Levels) that make up a digital photograph A basic 8-bit per channel grayscale image has a single channel and uses 256 shades of gray to describe all the shades of tone from black to white Black has a levels value of 0 (zero) and white has a levels value of

255 And all the numbers in between represent the shades

of gray going from black to white The histogram is like a graph with 256 increments, each representing how often a particular levels number (a specifi c gray color) occurs in the image If a picture contains mostly a lot of grays with number values of between 30 and 130 levels, you will expect to see a peak around the 30–130 levels point of the histogram graph Figure 4.1 shows a typical histogram and how the appearance of the graph relates to the tonal structure of a photographic image

Now let’s look at what that information can tell us about

a digital image The histogram show us the distribution

of tones in an image A high-key photograph will have lots of peaks towards the right of the graph and a low-key photograph will have lots of peaks to the left And most importantly, it shows the positioning of the shadow and highlight points When you apply a tonal correction using Levels or Curves, the histogram provides a visual clue that helps you judge where the brightest highlights and deepest shadows should be And the histogram also tells you something about the condition of the image you are editing

If the bars are bunched up at either end of the histogram, this suggests that the highlights or shadows are most likely clipped and that when the original photograph was scanned

or captured it was effectively under- or overexposed

Unfortunately, if the levels are clipped at either end of the scale you can’t restore the detail that has been lost And if there are gaps in the histogram, this will most likely indicate

a poor quality scan or that the image had previously been heavily manipulated

The histogram can therefore be used to check the quality of an image at the beginning of an edit session

If it looks particularly dreadful then maybe you should

Interpreting an image

A digital image is nothing more than a lot

of numbers and it is how those numbers

are interpreted in Photoshop that creates

the image you see on the display We

can use our eyes to make subjective

judgements about how the picture

looks, but we can also use the number

information to provide useful and usable

feedback The Info palette is your friend

If you understand the numbers, it can

help you see the fi ne detail that your eyes

are not sharp enough to discern And we

now have the Histogram palette, which is

a godsend to geeks who just love all that

statistical analysis stuff, but it is also an

excellent teaching tool The Histogram

palette will make everything that follows

much easier to understand

try rescanning the picture But must one be so absolutely pixel-correct about always obtaining a smooth histogram?

Any image editing you do will inevitably degrade the image Because after a picture has been manipulated the histogram will always look less smooth than it was at the beginning If you are preparing a photograph to go to a print press, you would be lucky to detect more than 50 levels of tonal separation from any single ink plate So the loss of a few levels at the completed edit stage does not necessarily imply that you have too little digital tonal information from which to reproduce a full-tonal range image in print But appreciate that if you begin with a bad-looking histogram, the image is only going to be in a worse state after it has been retouched, so start with the best image scan or capture

And in particular watch out for any signs of clipping

Figure 4.1 Here is an image histogram that represents the distribution of tones from the shadows to the highlights Because this photograph mostly contains dark shades of gray you will notice that the levels are predominantly located to the left end

of the histogram The height of each bar in the histogram indicates the frequency of pixels occurring at each level point.

The Histogram palette

There has always been a histogram in the Levels dialog and there is now also

a Histogram palette, which gives you even more feedback when working in Photoshop With the Histogram palette, you can continuously observe the impact your image editing has on the image levels You can also check the histogram while making curves or any other type

of image adjustment The Histogram palette only provides an approximate representation of the image levels To ensure that the Histogram palette is giving

an accurate representation of the image levels, it is advisable to force Photoshop to update the histogram view, by clicking on the Refresh button at the top of the palette

Figure 4.2 The warning triangle in the Histogram palette indicates that you need to click

on the Refresh button above to update it.