'3D Studio MAX'

'Compositing For Production Using 3DSMax and Mental Ray'
Lee Johnson

Step 32:

Select the top Solid Operator, and a Set Matte operator, and load the Case Matte element that you just rendered.  Now change the blending mode to Overlay (Fig.29).


Step 33:

Select the Shadow Layer, click on the Layer Button and adjust the Opacity to 40% (Fig.30).


Step 34:

Select the Diffuse Direct Illumination Layer, and copy and paste it.  Move the Diffuse Direct Illumination(2) to just above the original in the stack.  Add a Set Matte Operator and choose the Matte – Phone element.  Now go to Operator > Color Correction > Brightness/Contrast.  Set Brightness to 10% and Contrast to 50% (Fig.31).


Step 35:

Select the Reflection Layer, copy and paste it, and bring the new copy to just above the original.  Rename them “Reflection – Ground” and “Reflection Phone” (Fig.32).  You’ll notice that unlike the Diffuse Direct layer, the reflections have now doubled in brightness.  This is because of the Add blending mode.


Step 36:

Add a Set Matte Operator to the Reflection – Ground layer and choose the Matte Phone element.  Do the same for the Reflection – Phone layer.  Now adjust the Reflection Phone layer to 50% Opacity (Fig.33).  At this point we have lost the reflection on the ground plane.  To get it back we are going to invert the alpha channel on this layer.  But if you add the Invert Operator in the Workspace tab, you will invert the reflection layer, not the alpha.


Step 37:

Double click on “Composite – Blackberry” to make sure that is what’s being displayed in the viewport.  At the top left of the viewport, right click and choose “Schematic”.  In the empty part of the new viewport, right click and choose Flow Direction > Flow Up.  Now hit “Home” at the left side of Combustion. This is what’s called a node based view of your scene.  It looks crazy at first, but if you look at it for a minute then you’ll start to see the method of how it reads (Fig.34).


Step 38:

You can see the two Reflection Layers at the left. If you zoom in, you can see the Reflection Ground Node being fed by a Set Matte node.  The Set Matte Node is being fed by the Reflection footage and the Matte – Phone footage (Fig.35).


Step 39:

Right click on the blue wire connecting the Matte Phone footage to the Set Matte Operator of the Reflection Ground.  Add Operator > Channel > Invert.  Now you can control the reflections on the phone and on the ground independently.  And you’re only using one piece of matte footage (Fig.36).


Step 40:

If you really want to optimize your scene, you can wire one piece of footage into multiple operators and layers.  This allows combustion to load each piece of footage only once instead of multiple times.  For example, select the Matte – Phone node for Reflection – Ground.  Now delete it.  Move your mouse cursor over the red bar at the top of the Matte – Phone node for Reflection Phone until it changes to a crosshair.  Left click and drag a wire to the white bar at the bottom of the Invert Node of the Reflection Ground.  Now you have one piece of footage feeding two nodes.  This helps your scene load faster.  Repeat this for the Reflection and Diffuse Direct Footage (Fig.37).


Step 41:

Now grab your Art Director, and make yourself his hero by dialing in everything to his approval without having to wait for anything to re-render (Fig.38)!


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