Toolkit 2 - Maya: AOV's

  AOV means Average Order Value, and can be used to make the visuals of a image/model better.  

 Firstly with our model selected, we have to make sure the Displacement map is working correctly. Under the characters Attributes, we correct the Displacement map scale to 1. When doing this with the render viewer closed, it can cause some deformation. Closing the render viewer, place the map to 0 and then re-render. Changing the value whilst running will help resolve the overgrowth. 

Over Growth

  To create the AOV's, open the render setting and under the AOV's menu (Tab), we can place the desired effect into the outputs. When using the render viewer, we will be able to select them from the pull down menu. There are 4 different levels of AOV's, mixing these can cause composition problems. So, this means being careful in what we want to choose. 

 From these, we create following AOV'S 

- The ID pass (assigns colours to parts of the model for isolating).

- Diffuse Direct and Indirect.

- Specular Direct and Indirect.

- SSS (Sub-Surface Scattering)

-  Transmission

 We also need the Ambient Occlusion, but this will have to be a custom AOV. Clicking on create custom and naming as AO, we hook in a shader via the pull down menu, and select the AOV node. Under the shader on the AOV Attributes, we select aiAmbientOcculsion and increase the sampling to 5.  

ID AOV

Custom AOV: Ambient Occlusion

   Using AOV is a good way to dissect what is wrong with a models texturing. When completed, we save the image as 32 bit EXR file and place it into After Effects.

After Effects

  In After Effects, we change the depth to 32 bit so to be able to read the image correctly. Once dragged down into the workspace, we place a ExtractoR extension onto the file. This will firstly remove the color correction (gamma) and make it into a raw mode, whilst allowing us access to the AOV's from Maya.

Raw Colour

 Using the ExtractoR extension, we create all of our AOV's, turning them off as we go. Once completed, we select them all and pre-compromise them into one project. We want to bring back the colour as the image is very washed out, so under the utilities menu, we use the linear input profile under the colour profile converter. 

  Using a 2 window view in After Effects, we start adding in the Diffuse Direct and Indirect, SSS, Specular Direct and Indirect, finally Transmission via the layer menu. The Ambient Occlusion is placed as a multiply and is reduced down to 33%. This stops complete darkening of the image. 

  For the SSS layer, we place in a Brightness and Contrast extension to lighten up the skin colour again. Moving on to the ID layer, we bring it to the final render project and place a Linear Colour Key over the top. Selecting the colour of the left eye with the eyedropper tool, we bring down the softness to 0 and the tolerance to 1. Track Matt allows us to isolate it completely, a whilst placing Brightness and Contrast key on the layer will help bring the colour out more. These two layers are duplicated, and then process repeated for the right eye. 

  To export, we select the final render project, make sure its on fame 0 and use the Save Frame Menu (Composition), file. This will save a PSD format, so we can check that there is no blow out. 

Final Image