Arnold Render Farm | Fox Render Farm

A friend asked me before, how to make LightGroup in Arnold 5.1 version, because with LightGroup, we do not need to divide the Light Render Layer. The method of Arnold 5.1's LightGroup is not the same as the previous version. I remember that the LightGroup property was added to the light at the beginning. This method only works for the alshader's shader, and then the light property bar is added in the AOV Light Group column, add LightGroup1 by ourselves in the AOV attribute, and apply the L.'LightGroup' command. After the Arnold 5.1 version, it was found that this method has failed. Even if you add the L.'LightGroup command to AOV, still not working. Next, let me talk about how Arnold 5.1 makes LightGroup. The first step is to create a light. In the AOV Light Group property column of the light, give it a name that you want of this LightGroup, I name it LGT_A here. The second step is to add the RGBA ([cloud rendering](https://www.foxrenderfarm.com/cloud-rendering.html) note that, it is must in uppercase) channel to the AOV channel. Why should we add the RGBA channel? Because I found that only the RGBA channel has its Light Group List property bar showing its effect. If you add a LightGroup channel, you will find that this property is in the closed state, and this RGBA must be uppercase, quite fucking. Then enter the RGBA channel properties and select the LightGroup you added to the Light Group List option. My scene made 3 lights, so there are three. LightGroup appears after the rendering below. Here is the rendering of render farm test:

Yesterday, I found that the Arnold of Maya 2018 has a directional error for the motion vector blur method made in the AOV channel. The motion blur method I wrote earlier applies to Maya 2016 and earlier versions, so I spent a little time studying it today. The problem has been solved now, and cloud rendering will use a small case to explain the production steps. Step 1: Creating the ball as a simple animated scene. Step 2: Turn on motion blur: Render a reference to motion blur. Step 3: Follow the method given in the official Arnold documentation: Change the camera's Shutter Start and Shutter End to 0.5 (why changed to 0.5 because my motion blur type is Center On Frame). Step 4: Create a channel for AOV motion blur: Here I will create two motion blur channels: The first is the motionvector channel that comes with Arnold. The second is to use the custom motion vector AOV of motion vector shader (giving the aiMotionVector material in the AOV channel). Cloud rendering note: MBlur is named according to your preference. The setting of aiMotionVector was wrote in the previous article. Step 5: Render this image to see two motion blur conditions. It can be seen that both the motionvector and MBlur motion blur channels in our AOV channel are in the wrong direction. Step 6: Next I will officially explain how to solve this problem: From the beginning. A: Turn on the Motion Blur button in the render settings: I chose the Center On Frame mode here. B: Change the Shutter Start and Shutter End in the camera Arnold attribute to 0.5, respectively, corresponding to the Center On Frame mode. (Note: When rendering the motion vector AOV, the camera Shutter Start and Shutter End should be the same value.) C: Create a new MBlur_2 channel in AOV (to compare with the previous MBlur.) D: Open the material editor and find the two nodes aiMotionVector and aiVectorMap under Arnold's material panel. 1) Connect the outColor of the aiMotionVector node to the input of the aiVectorMap node. 2) Then connect the outValue in the aiVectorMap node to the DefaultValue in the Shader property of the MBlur channel in AOV. Change the XYZ mode of the Order in the aiVectorMap node to YZX mode and remove the hook of the tangentSpace. 4) In the aiMotionVector node, enable Encoding Raw Vector. E. After the above steps are completed, start rendering the image and view it in Nuke. As shown in the figure: Maya's default motion blur is basically the same as the MBlur_2 channel we made in AOV, and the motion blur adjusted by Nuke is basically the same. Of course, I also found a bug in the Arnold renderer, its motion blur channel does not solve the shadow of motion blur, there can be seen in a big picture that cloud rendering attached below.

Arnold's motion vector channel has always been a bug. Today render farm are talking about another way to implement the correct Arnold motion vector channel. Step 1: Turn on Motion Blur Step 2: Manually create an MBlur channel (named according to your preferences) Step 3: Create two nodes aiUtility and aiMotionVector respectively Tick aiMotion Vector's Encode Raw Vector Assign aiMotionVector to aiUtility's color Change aiUtility's Shade Mode to Flat Step 4: Change Shutter Start and Shutter End to 0.5 under the camera property Arnold menu that you are rendering. This ensures that the rendered material layer is free of motion blur and that the AOV channel has the correct motion vector channel. Cloud rendering give you a note: The values of Shutter Start and Shutter End under the camera properties for the three motion blur modes.