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Basic techniques for vray advanced

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Here are the basic VRAY settings I use for exterior Lighting: < Turn off Default Lights.. < Make sure the settings are the samenote these settings are optimized for fast render times Cli

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Basic Techniques For Vray Advanced

This tutorial is intended to get you started using Vray If you find something that you think I

need to change please email me.

Here are some other sites with Vray tutorials that I find useful:

www.chaosgroup.com/support(you will have to register) click on "V-ray docs" and open the Help

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Page 2Basic VRAY Tutorial

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1.1 Download Basic_VRAY_Tut_Start.max

1.2 Render the scene You should get something silimal to the image above Here are the basic

VRAY settings I use for exterior Lighting:

< Turn off Default Lights

< Use Adaptive Subdivision (for

now)-

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< Primary Bounces: Irradiance Map

(IR Map)

< Secondary Bounces: Quasi-Monte

Carlo (QMC)

< GI Environment: Check Override

Max's and set color to the ambientcolor of your choice (SceneDependant)

< Reflection/Refraction: Check

Override Max's (this isn't importantnow but it will be for HDRI lighting)

< QMC Sampler: these settings may

be a little high for now but we'll getinto that later

< Current Preset: Set this to custom.

< Make sure the settings are the same(note these settings are optimized for

fast render times) Click show calc phase if you want to see what VRAY

is doing during the IR Map passes

<Advanced Options: Blah, blah and

more blah

< Leave this alone as well

2. Environment Adjustmnets

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Page 4Basic VRAY Tutorial

Here is an example of what can happen to a scene if the environment is too high As you can see

the entire image looks blown out and oversaturated

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As you can see this approach produces shadows that are very soft and undefined This method maywork for you depending on the look you are after You can add a bitmap to the GI Environment by

clicking "None" and browsing to a bitmap of you choice (Adding a bitmap to the GI environment is

similar but but the same as HDRI lighting which we will cover later on)

3 Night Scene

Even on the darkest nights in the middle of nowhere there will always be some sort of "ambient light"(varying degrees of course) Light from the stars, moon, or like in many night scenes, light from

surrounding buildings and gereral "civlilization" can create enough ambient light to see an

object even if the object has no light source of its own (All of this depends on the scene you are

rendering) A good way to get this general ambient light is to use the GI environment

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Page 6Basic VRAY Tutorial

3.1 Set you GI Environment to 4 and pick a similar color to the one below.

3.2 Make sure the light Direct01 is off and then select and turn on the light "Inside Omni" This light

simply provides some interior lighting so its not so dark

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The VRAY light material allows you to create a light out of any piece of geometry I applied a VRAYlight material to the sphere on top of the structure.

4.1 Open the Material Editor (M), click on an empty material slot and click the top right button that

says "Standard" (If the button says VRayMtl then you didn't select an emty slot)

4.2 When the Material/Map browser opens select VRayLightMtl near the bottom of the list as shown

below:

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Page 8Basic VRAY Tutorial

Back in the Material editor you can adjust the settings of your Vray Light material Play with the color

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Aslo you can use a standard MAX material with self illumination to produce geometric lights See

Example below

The curving tube has a rainbow bitmap in the map slot under self illumination The material is a

standard MAX material

5 Color Bleeding

5.1 Turn off the light "Inside Omni" and turn on the Light "Direct01".

5.2 Under VRay Environment, adjust the GI Environment as we had it before when we made the

direct sunlight renders Give the multiplier a value of 3 and adjust the color back to a light yellow

5.3 Select the sphere on the top of the structure and assign the "Yellow1" material to it.

5.4 Render the Scene and you should get a result similar to the image below:

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Page 10Basic VRAY Tutorial

Roll over the image to see the effects of color bleeding Light is bouncing off the sphere and onto

the surrounding objects Though this effect does happen in the real world, I often see it over

exaggerated in renderings You can desaturate your materials (or their corresponding bitmaps) to

lessen this effect

6 VRAY Toon

6.1 From the top menu click Rendering then click environment (Or just press "8") This brings up the

Environment and Effects Dialog box

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6.2 Under the Atmosphere rollout click the "Add" button Select VRay Toon from the list that

appears

6.3 Scroll down a bit in the Environment and Effects Dialog box to see the VRay Toon settings and

change the line from pixels to world by clicking on the "World" radio button Give the line thickness aworld value of 6" as shown above

6.4 Render the scene You should get a similar result to the image below:

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Page 12Basic VRAY Tutorial

Note: You can modify the color and thickness of the line to get desired results Also you can use a

custom bitmap in the color slot of the line if you prefer

7 Interior Lighting

7.1 Switch to Camera02 and make sure the light "Inside Omni" is turned off.

7.2 Press "8" to open the Environment and Effects dialog box Under the Atmosphere rollout select

VRay Toon from the Effects list With VRay Toon selected click the delete button For this example

of interior lighting we want the VRAY Toon effect turned off

7.3 Select Pane01, right-click in the viewport and select VRay properties:

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7.4 With the VRAY Properties box open check "Matte object" in the top right Under Direct Light

check shadows The Matte object makes the plane invisible but it will still render the shadows and

reflections (Useful for studio lighting setups) We did this so that the ground plane wont show up inthe interior render (Also to explain Vray object properties) There are many useful settings in the

VRay object properties box their labels are self explanitory

7.5 Render the scene It should look like the image below:

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Page 14Basic VRAY Tutorial

It is obviously to dark As cool as VRAY is, most of the time it needs some help lighting interior

scenes In other words, a Direct light alone isn't enough This is where the VRay Lights at the

windows come in Notice they are positioned right outside of the window (adjust the positioning to fityour specific needs) and are the same shape as the window

7.6 Select VRayLight01 and click the modify tab on the control panel

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7.7 Turn on VRayLight01 by clicking the checkbox under the Parameters rollout The other five

VRAY lights in the scene are instances of Light01 and should turn on as well Make sure "Invisible"

is checked If it isn't, the light from Direct01 won't be able to pass through the VRay Lights

7.8 With the lights on, render the scene You should get a result similar to the image below:

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Page 16Basic VRAY Tutorial

The image looks somewhat grainy with the default VRay Light settings To correct this we can

change some settings in the VRay QMC Sampler rollout

7.9 Open the Render Scene dialog box if it isn't open already (press F10)

7.10 Click the Renderer tab and scroll down to the "VRay QMC Sampler" rollout and expand it if it

isn't alread open

7.11 Adjust you settings to match the image below:

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7.12 Render the scene.

Notice how the adjustments we made reduced the graininess to a more tolerable level However, the

render time has doubled You'll have to toggle the settings in the QMC Sampler until you reach a

level that optimizes quiality and Speed This is easier said than done and of course it varies from

scene to scene

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Page 18Basic VRAY Tutorial

Comparison of settings The yellow arrows show the dividing line of the same scene with the

different settings

8 HDRI Lighting

High Dynamic Range Image (HDRI)

The HDRI file used in this tutorial was created by Aversis Visit www.aversis.be for more

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8.2 Render the scene You should get something similar to the image below.

The scene is lit only by the light Direct01 and GI bounces

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Page 20Basic VRAY Tutorial

8.3 Press "M" to open the Material Editor Click on theVRay HDRI material in the top right.

Note: To load a VRay HDRI file select an empty material slot and click the blue "Get Material"

button which is highlighted in yellow above When the Material/Map Browser opens, select

VRayHDRI from the list highlighted in yellow below

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8.4 Drag the HDRI material from the material editor into both environment slots located in the VRay

Environment rollout of the render scene dialog box

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Page 22Basic VRAY Tutorial

Choose instance when promted and click ok

8.5 Before we render the scene we need to turn off the light Direct01 and make sure that the GI

Environment multiplier is set to 1 (highlighted in yellow above) Since the only thing lighting the

scene will be the HDRI light, the GI Environment multiplier needs to be higher Note: You can, for

example, use a direct light (sunlight) in conjunction with HDRI lighting But, its a good idea to have

one more powerful than the other to avoid burnt out images (see section 2) Make sure your HDRI

parameters are the same as the image above (play with the settings later)

8.6 Render the scene Your results should be similar to the image below.

The shadows are much softer and undefined The look is similar to straight environment lighting

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Note: HDRI file was created by Aversis Visit www.aversis.be/extra_hdri/00.htm to download more of his HDRI files and browse his VRAY tutorials.

This is what the HDRI file we are using looks like This is the image that is lighting our scene The

soft shadows in the scene are produced because of the Real World soft shadows captured in the

HDRI file

9 Material Settings

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Page 24Basic VRAY Tutorial

9.1 Give the Green, Red and Yellow1 materials a light grey color in the reflection slot You can copy

the color by right clicking the color and pasting it into the reflection slots of the other materials Seeimage below

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9.2 Render the scene Your results should be similar to the image above.

Settings for the glass:

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Page 26Basic VRAY Tutorial

Settings for the water:

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Page 28Basic VRAY Tutorial

Note: I used the turbulance noise preset but use what you think will work best for your situation You

can animate the bump amount to create a ripple effect in animations

9.3 Glossy Reflections

Change the settings for the red, green and yellow materials to match the following (Leave the

diffuse colors alone)

Results should be similar to the image below:

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Frosted Glass:

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Page 30Basic VRAY Tutorial

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The refraction glossies has been lowered to.95 I find this to be a little counter intuitive, but to

increase glossieness you have to lower the spinner

Note the increase in render time For animations you might want to find another way to achieve this

effect Remember we are still using Basic render settings Our custom Irradiance Map (IR

Map) is setup for quick rendering Higher quality IR maps will and higher output resolutions will significantly increase render times That being said I have managed to render animations

with moving objects using these "low" custom IR map settings without any noticable "flickering"

The flickering problem well thats a whole other tutorial in itself

10 VRAY Displacement

No steps to follow here just some examples and settings

A plane with a VRay Displacement map applied to it

Here is the plane without the VRay displacement Map

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Page 32Basic VRAY Tutorial

Plane with displacement

This is the Map:

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And the displacement map:

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Page 34Basic VRAY Tutorial

Remember that the white areas get extrude the most and the black areas extruded the least Keepthat in mind otherwise you may get unwanted results I spent some time in Photoshop making

certian ares pure white or pure black in order to aviod "spikes" in the displaced geometry.

To Apply:

1 Select the object you want to apply the VRay Displacement to.

2 Apply a Mesh Smooth Modifer to the object and set the iterations to zero.

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Page 36Basic VRAY Tutorial

4 Adjust the settings to match the image below:

In the common params, highlighted in yellow, there is a button to add a bitmap for displacement

This is where I added the black and white stone image seen above

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