BASIC TECHNIQUES FOR V-Ray ADVANCED

TOPICS COVERED:

1. Exterior Lighting
2. Environment Adjustments
3. Night Scene
4. V-Ray Light Material
5. Color Bleeding
6. V-Ray Toon
7. Interior Lighting
8. HDRI Lighting
9. Basic Material Settings
10. V-Ray Displacement

Download Basic_V-Ray_Tut_Start.max
NOTE: THE MAX ONLY WORKS WITH MAX 8 OR HIGHER

1. Before we begin do the following:

- Global Switches: Turn off Default Lights.
- V-Ray Image Sampler: Use Adaptive Subdivision (for now)
- V-Ray Indirect Illumination (GI): Make sure GI is turned ON.
- V-Ray Indirect Illumination (GI): Use Irradiance Map (IR Map) for Primary Bounces
- V-Ray Indirect Illumination (GI): Use QMC for Secondary Bounces

- V-Ray Environment: Under GI Environment Check Override Max's and set color to the ambient color of your choice (Scene Dependant)

- V-Ray Environment: Reflection/Refraction: Check Override Max's (this isn't important now but it will be for HDRI lighting)

- V-Ray QMC Sampler: These settings may be a little high for now but we'll get into that later.

- V-Ray Irradiance Map: Set the current preset to custom.

- Make the basic Irradiance Map parameters match those in the image (they are optimized for fast render times)

- Leave all other settings default for now

 

2. Environment Adjustmnets

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.

 

 

Setting the GI environment to .6 caused the result above.

Note: The "blown out" effect is also due to the Target direct Light in the scene. In combination with lights, high GI Environment multipliers can cause unwanted results. By contrast it is possible to light a scene using only the GI Environment

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2.1 Increase the GI Environment Multiplier to 1.0 and turn off the Target Direct Light (Direct01)

2.2 Render the scene

As you can see this approach produces shadows that are very soft and undefined. This method may work 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

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

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.

 

 

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.

3.3 Render the scene and you should get something similar to the image on the left.

 

 

 

4. V-Ray Light Material

The V-Ray light material allows you to create a light out of any piece of geometry. I applied a V-Ray light 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 V-RayMtl then you didn't select an emty slot)

4.2 When the Material/Map browser opens select V-RayLightMtl near the bottom of the list as shown on the left.

 

 

Back in the Material editor you can adjust the settings of your V-Ray Light material. Play with the color and multiplier to get the desired results

 

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Aslo you can use a standard MAX material with self illumination to produce geometric lights. The curving tube has a rainbow bitmap in the map slot under self illumination. The material is a standard MAX material.

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5. Color Bleeding

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

5.2 Under V-Ray 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 on the left

 

 

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

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6. V-Ray 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.

6.2 Under the Atmosphere rollout click the "Add" button. Select V-Ray Toon from the list that appears.

6.3 Scroll down a bit in the Environment and Effects Dialog box to see the V-Ray Toon settings and change the line from pixels to world by clicking on the "World" radio button. Give the line thickness a world value of 6" as shown above.

 

 

 

6.4 Render the scene. You should get a similar result to the image on the left.

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 V-Ray Toon from the Effects list. With V-Ray Toon selected click the delete button. For this example of interior lighting we want the V-Ray Toon effect turned off.

7.3 Select Pane01, right-click in the viewport and select V-Ray properties as seen on the left.

 

 

7.4 With the V-Ray 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 in the interior render. (Also to explain V-Ray object properties) There are many useful settings in the V-Ray object properties box...their labels are self explanitory.

 

 

7.5 Render the scene. It should look like the image on the left.

It is obviously to dark. As cool as V-Ray 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 V-Ray Lights at the windows come in. Notice they are positioned right outside of the window (adjust the positioning to fit your specific needs) and are the same shape as the window

 

 

7.6 Select V-RayLight01 and click the modify tab on the control panel

7.7 Turn on V-RayLight01 by clicking the checkbox under the Parameters rollout. The other five V-Ray 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 V-Ray Lights.

 

 

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

The image looks somewhat grainy with the default V-Ray Light settings. To correct this we can change some settings in the V-Ray 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 "V-Ray QMC Sampler" rollout and expand it if it isn't alread open.

7.11 Adjust you settings to match the image below:

 

 

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.

 

 

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 tutorials on HDRI lighting and many other V-Ray topics.

8.1 Switch to Camera03 and unhide the following objects: Bowl, Glass, Teapot, Torus Knot and Water.

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

 

 

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

 

Note:
To load a V-Ray 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 V-RayHDRI from the list...highlighted in yellow on the left.

 

 

8.4 Drag the HDRI material from the material editor into both environment slots located in the V-Ray Environment rollout of the render scene dialog box. 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 described in section 2. However, there are subtle differences. Don't think that HDRI lighting only produces soft shadows. If many cases it does, but that's because the majority of shadows in the real world have soft edges and HDRI intends to accurately re-create real world lighting conditions.

 

 

 

9. Material Settings

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. See image below.

 

 

 

 

WATER SETTINGS
Note: I used the turbulance noise preset but use what you think will work best for your situation. Yo

9.3 Glossy Reflections

Change the settings for the red, green and yellow materials to match the following. (Leave the diffuse colors alone) Adjust the Refl. glossiness to .85. The lower the value the more glossy the material.

 

 

Render the image. Results should be similar to the image on the left.

 

 

FROSTED GLASS SETTINGS

LOWER THE REFRACTION GLOSSINESS
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."

 

10. V-Ray Displacement

No steps to follow here just some examples and settings.

On the left is a plane without a V-Ray Displacement map applied to it.

 

 

 

Plane with displacement applied.

 

 

<Here is the diffuse map

<Here is the displacement map

Remember that the white areas get extruded the most and the black areas extruded the least. Keep that 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 create a V-Ray displacement map

1. Select the object you want to apply the V-Ray Displacement to.

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

 

 

3. Apply a V-Ray Displacement modifier.

 

 

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.