× Indoor shots using incandescent light bulbs 3000K å Indoor shots using fluorescent lighting 4200K ® Outdoor shots in direct sunlight 5200K ç Indoor or outdoor shots lit primarily by fl
Trang 1õ To set compensation hold the £ button on the top right side of the camera and rotate the Rear Command dial until the value you want is shown in the top LCD You can also see the value while looking through the viewfinder
Note: Choose the exposure compensation increment (third, half,
or full stopsF
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) with Custom Setting #B4 (see page <H438>)
Once set, exposure compensation remains set until you use
the control again and set a value of 0.0
Note: In Manual exposure mode, exposure compensation is
“invisible.” The zero point is moved when exposure
compensation is set Try it Set a correct exposure in Manual exposure mode and then dial in compensation: you’ll see that the manual exposure indicator moves off of 0 in direct relationship to how much compensation you dialed in
The D200 supports an alternate method of setting exposure compensation via Custom Setting #B5; see “Exposure
Compensation Control” on page <H439> When you set this alternate method, called “Easy Exposure Compensation” by Nikon, one of the command dials on the camera is used to
adjust compensation values, even when the £ button is not held down! (Which dial is used depends upon your exposure
mode and the value of Custom Setting #F5.) Frankly, I think this is a dangerous ability because if you forget that you have
it set, you may not notice that you’re setting compensation instead of apertures or shutter speeds Some D200 users do
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Half stops are shown in a series like this: 0.0, 0.5, 1.0, 1.5, 2.0, and so on Third stops are always rounded and are shown as 0.0, 0.3, 0.7, 1, 1.3, 1.7, 2, and so on
Trang 2find it useful, though, because they always shoot in one exposure mode (usually Aperture-preferred) and it gives them
a convenient way to quickly take an exposure at a value different from the metered one (i.e take a picture, twirl a Command dial (usually Rear, as the aperture is controlled by the Front), take another picture at the compensated setting)
White Balance
All light is not created equal The perceived color of an object depends upon the light source that illuminates it Our brains, however, are pretty good at overriding what our eyes see If someone wearing a white shirt walks from the sun into the shade (where the light is usually “bluer” due to reflections and light scatter), our brain knows that shirt itself isn’t getting bluer, even though the light being reflected by the shirt is now reflecting a bluer light
Unfortunately, both film and digital cameras respond to light
in a fixed fashion, so the resulting image taken with a camera
will reveal the shirt to be a bluish white in shade and a bright,
neutral white in the sun
Color temperature is an objective measurement that defines the temperature at which a “black body” object would have
to be heated to radiate light in the same wavelengths Color temperature—the color of light—is expressed in units of Kelvin Though it measures temperature, units of Kelvin do not get a degree mark, just a K (e.g 5200K, not 5200°K) Lower numbers indicate a “redder” light (to our eyes), higher numbers indicate bluer light The light itself isn’t “red,” it just has more red wavelength components than, say, a “bluer” light (which would have more blue wavelength components)
On digital cameras, you set a “white balance” to adjust the sensor to the wavelengths of light being captured D200’s have nine basic white balance settings:
â or A Automatic white balance Nikon claims that this
function works at any color temperature between 3500K and 8000K Note that most indoor lighting
Trang 3falls below that range! Moreover, my experience
tells me that the D200 gets less accurate towards the extremes I’d say the most accurate range is much narrower, perhaps 4500 to 6200K
× Indoor shots using incandescent light bulbs
(3000K)
å Indoor shots using fluorescent lighting (4200K)
® Outdoor shots in direct sunlight (5200K)
ç Indoor or outdoor shots lit primarily by flash
(5400K)
æ Outdoor shots in overcast skies (6000K)
ã Outdoor shots taken in shaded areas (8000K)
ä Manually set white balance using a white or
neutral object (Nikon doesn’t specify a range, but
we know that you can manually adjust a D200 from 2500K to 10,000K, so the range should be at least that wide)
K Individual Kelvin values can be set
Note: Digital cameras fare less well using the Automatic white
balance setting with light that falls under 4000K (note that
Nikon doesn’t recommend Auto below 3500K for the
D200; yet I find that even at 4500K the camera tends to set
a white balance that’s a bit too high in Kelvin for the light) That’s partially because the blue sensors receive very little information at these so-called “warm” color temperatures,
so the minute amount of blue wavelengths being seen by the sensor become a factor
One novel way of coping with the problem of getting good automatic white balance with indoor light is to simply imitate what we used to do with film: use an 80B filter! The 80B shifts the 2900K color temperature of a 100-watt bulb
up to about 4300-4400K (an 80A would push it above 5000K), putting it within the range the camera handles well Tip: Nikon’s choice for normal outdoor lighting (5200K) should
raise eyebrows, though I haven’t seen anyone specifically
Trang 4comment on it Daylight film is usually balanced to 5400K, and many digital photographers set their default daylight value even higher (The origin of the 5400K number, by the way, is interesting—it’s the average measurement of color temperature, taken at noon on summer and winter solstice
on the Mall in Washington DC in 1926! Since altitude, time
of day, time of year, cloud cover, and distance from the equator all alter daylight color temperature, one value does not apply to every situation.) Don’t be afraid to experiment
a bit to find the white balance you like best In general, I
find that Flash -2 is the quickest way for me to set a sunny
white balance I like, and I also tend to use much higher color temperature values than Nikon suggests for most
indoor lighting (e.g Incandescent -1 or –2)
The D200 detects white balance in two different ways: (1) via the 1005-pixel sensor in the viewfinder; and (2) via the main imaging sensor itself Nikon doesn’t reveal how these two systems interact, but it’s clear to me that the D200 has less accurate automatic white balance than the D2x, which has a dedicated white balance sensor
Let’s look at color temperature in action Since color
temperature for daylight was originally determined on the Washington Mall, let’s go there for our test Below you’ll find
a photo taken late in the day (in late April) of the Lincoln Memorial I’ve tweaked this photo a bit to saturate the colors and tone down the sky (which also has a graduated neutral density filter holding it back), but if you were standing next to
me at the time, this would be pretty close to what you saw:
Trang 5The left portion of the monument is the area we’ll work with (though note the slight orange areas under the eaves in the front—we’ll be coming back to those in a moment) Let’s look
at a number of options for white balance:
From left to right: 3400K, 3800K, 4400K, 4800K, and 5200K I’ve added just a bit of color saturation to emphasize the cast All photos taken at the same camera settings and processed through Nikon Capture the same
You should notice in the above examples that as the color temperature on the camera is set lower than the actual value present in the lighting, a blue cast appears in the photo (That again brings up Nikon’s choice of 5200K for Daylight—most
of the time you’ll find that it generates results that are slightly
on the blue side)
The further we get from the actual color temperature, the more distinct that cast is Note, too, that the cast applies to
Trang 6everything: sky, building, and bushes It isn’t until you get 5200K that we begin to see some of the warmth that is in the limestone and sky, and it isn’t until we get over 5500K that the greens actually become fully green (no hint of blueness; compare the larger photo with the rightmost small one and look at the greens)
Remember those orange spots on the walls of the Memorial? Those are areas lit by incandescent light, which has a lower color temperature than daylight Inside the Monument, Lincoln’s bust is mostly lit by incandescent lighting Here’s another full photo to consider:
Lincoln Memorial at night, when only the internal overhead lighting contributes to color temperature
Now we’re dealing with mostly incandescent lighting, which has a lower color temperature (most bulbs used on large buildings like this one are of the Photoflood variety, and about 3200K in output) There’s a bit of overhead fluorescent
in the Monument as well, but the incandescent pretty much overwhelms it where Lincoln sits
Trang 7From left to right: 3000K, 3200K, 3400K, 5000K, 6000K All camera settings and Nikon Capture settings otherwise the same
You should notice in the above examples that as the color temperature on the camera is set higher than the actual value
of the lighting, a red/orange cast appears in the photo The further we get from the actual color temperature, the more distinct that cast is
So remember that orange cast on the outside of the building? That was caused by setting a color temperature higher than the actual color temperature Most of the building was lit by the sun and sky, so the color temperature on those portions of the building was high (5500K to 6000K based upon my observation) The spots under the eaves that are orange were lit by incandescent light that was close to 3400K Thus, if the rest of the building is rendered correctly, those spots turn orange
This illustrates a common problem: in many scenes, there is
no single color temperature of light that affects everything An area in shade on an otherwise sunny day may be slightly higher color temperature than that in direct sun Indoors you may find both incandescent and fluorescent bulbs lighting different areas If the different lighting sources are equally mixed on your subject, you can use the Preset method of setting white balance and measure the value off a gray card (see below) But if the areas of different lighting are separate—incandescent lighting a foreground subject and fluorescent lighting a background, for example, you have to pick a color
Trang 8temperature and live with the results, as I did in the photo outside the Lincoln MemorialF
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õ To set the white balance: press and hold the WB button while rotating the Rear Command Dial until the icon for the desired method is shown on the top LCD The Front
Command Dial can be used to control the fine tuning of white balance (setting –3 to +3 increments on the basic value—more on that in a bit)
Alternatively:
1 Press the MENU key to show the menu system
2 Use the Direction pad to navigate to the SHOOTING MENU (camera icon tab)
3 Use the Direction pad to select the White Balance
option and press the > key on the Direction pad to see the submenu
Trang 94 Use the Direction pad to highlight the white balance option you want and press the > key to select it
5 Use the % and " keys on the Direction pad to set any fine tuning you desire and the > key to complete the setting
Nikon only provides a cryptic system for indicating the fine tuning changes (whole numbers from –3 to +3, where
negative numbers set a higher color temperature while positive numbers make the color temperature lower—what
was Nikon thinking?F
I don’t know But here’s what you should be thinking: higher values make for
cooler-looking pictures; conversely lower values make for warmer photos
Trang 10D200 White Balance Settings
Approximate resulting color temperatures are:
_Approximate Kelvin value _
-3 -2 -1 0 +1 +2 +3 Incandescent 3300 3200 3100 3000 2900 2800 2700
The asterisk indicates that these white balance values are not
color pure—Nikon uses hue adjustments to shift the colors to
better match the odd balances of fluorescent tubes Because
fluorescent lighting uses colored phosphors that don’t
produce the entire light spectrum, and because those
phosphors decay at different rates, most digital cameras have
fluorescent settings that attempt to deal with the
overabundance of green/blue values such light produces The
D200 does this, too If you use the fluorescent white balance
settings on light that was produced by a continuous spectrum
light source (most other lighting), you’re likely to see a cyan
and/or green shift.)
Put another way, here are the changes in color temperature
from the middle setting:
Change in Kelvin value
tuning increments that are small, others span over a much
wider range Fortunately, Nikon also allows you to set a
Trang 11specific Kelvin value in 10 MIREDF
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increments from 2500 to 10,000K
Let’s put those D200 preset and settable Kelvin values in context of actual lighting sources (all values except the first can be set on the D200 in some way):
1930K Candlelight (value can’t be set on D200) 2500K (lowest value that can be set on D200) 2550K
Trang 125200K DIRECT SUN, Carbon arc lighting (movie sets)
9200K SHADE -3, Shaded area in hazy sun
Note: If you also use a D1H or D1X, most of the named values
that were just shown are the same, though Nikon has made
a few shifts in the Incandescent values The D2 series,
D70, D100, and D200 share the same Kelvin values
The D200 also allows you to measure the lighting in a
particular location and manually select an appropriate white
balance using the PRE selection To select and set a white balance of PRE, there are additional steps you must take
õ To set white balance from a neutral reference source (if the
white balance is already set to PRE, you can skip to Step 7):
Trang 131 If the camera is in Manual exposure mode, set a correct exposure for the gray or white card you’ll use
in Step 8, below, before proceeding
2 Press the MENU key to show the menu system
3 Use the Direction pad to navigate to the SHOOTING MENU (the camera icon tab)
4 Use the Direction pad to navigate to the White
Balance option and press the > key on the Direction
pad to select it
5 Navigate to White Balance Preset and press the >
key on the Direction pad to select it
6 Navigate to the White Balance preset you wish to save
the value to (D-0 through D-4 are available) and press the ENTER button to select it
Trang 14a You can name your presets Press the center of the Direction pad You’ll see a new menu:
b Use the Direction pad to navigate to Edit
Comment and press the > key to select it
c Enter your name for the preset (Direction pad navigates to a letter, center of the Direction pad inputs the currently highlighted letter,
ENTER button ends the entry; same key
functions as in Image Comment)
d Your preset should now have a name (note bottom area of screen shot):
Trang 157 Press and hold the WB button on the camera until PRE
begins flashing on the top LCD and in the viewfinder
8 If you wish to measure off a neutral gray or white card, frame it fully in the viewfinder and press the shutter release
9 If an acceptable white balance value was measured, you’ll see GOOD on the top LCD (GD in the viewfinder)
If the camera couldn’t get a usable reading, you’ll see
NO GD in both the top LCD and the viewfinder If you see NO GD, return to step 7 and try again
If you see NO GD instead, check your exposure and try again
Note: You can perform the naming step (Step 6, above), after
you’ve performed the white balance, but I generally prefer
to do it in the order listed
To set a white balance from an existing photo:
1 Press the MENU key to show the menu system
2 Use the Direction pad to navigate to the SHOOTING MENU (the green camera icon tab)
3 Use the Direction pad to navigate to the White
Balance option and press the > key on the Direction
pad to select it