'3D Studio MAX'

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

Step 24:

Back in the Workspace Tab, select the top Paint Operator.  Right click and choose Operators > Channel > Set Matte.  Click on the button that says (none) and then click on Open Footage.  Now browse to and select “blackberry_illum_mask.png”.  Click “Load Selected Image Only” and click OK.  Add a Glow Operator,  Strength: 0.5 and Radius: 4.  Please note: If you go back and do this with the full rendered sequence, you’ll need to reload this footage, and set it to Load Image Sequence, and set the Frame Rate to 30.  Also you will need to track the Filled Shapes to cover the buttons as the phone rotates (Fig.22).


Step 25:

Now in the next step you’ll add a Depth of Field Blur as a post effect.  This is not as accurate as rendering it in 3D, but it’s much faster and adjustable on the fly.  However this still takes some time to calculate in 2D, and since this takes a lot of adjusting to get what you want, it’s not a bad idea to save your workspace.  So go to File > Save Image, and choose a format type and output directory to get a snapshot of what you have so far.  Close this workspace and open a new one, and import the image you just made (Fig.23).


Step 26:

On the blackberry footage add Operators > 3D post > G Buffer builder, and then Operators > 3D Post > 3D Depth of Field. Click on the G Buffer Builder operator and then on the Z buffer slot.  Choose Footage, and browse to where the ZDepth Element you rendered is saved.  Click OK (Fig.24).


Step 27:

Under the 3D Depth of Field operator, set the blur high, around 10 or so.  Now start adjusting the Z Near and Far values of both the G Buffer Builder and the 3D Depth of Field operators.  The large blur will let you see more interactively what the effect is.  This takes some practice to get what you want, so use the following values and then adjust to your liking (Fig.25): 
*G Buffer  Near:  -2000
*G Buffer Far: -600
*3D Depth of Field Near : -1500
*3D Depth of Field Far: 0 

When you get the ranges set, adjust the blur to more what you want.  I used 5.  Please note: You will need to stick with the Box Blur type.  The Gaussian blur, while better looking, requires other element outputs to be loaded in the G Buffer Builder.


Step 28:

Go back to your original workspace.  Highlight “Composite” in the top of the Workspace window and add your G Buffer and 3D DOF operators.  Load the ZDepth footage, and enter the ranges from before (Fig.26). Now you have it all in one file.


Step 29:

So you’ve put all these elements together, and fixed that little problem with the material on the buttons.  Seems like you’re all done.  Well this is usually when your Art Director comes over and says, “The reflections on the phone are too strong; I’d like the lighting on the phone to be brighter; the shadow is not dark enough; the client just called and said they want the case to be red instead of grey.”  If you have not rendered everything in passes, this requires going back to 3ds Max, changing settings and re-rendering everything.  Then you run the risk of spending render time on settings that are closer to what the Art Director wants, but not guaranteed.  You could spend 3-4 rounds of this getting everything just right.  But since we rendered everything in layers we can do most of the fixes in post.  First let’s go back to 3ds Max for a few things we need.

Step 30:

Open “blackberry_elements.max”.  Select the BlackBerry in the viewport, and go to Group > Open.  Now go to the Render Elements Tab, and add a Matte Element.  Rename it “Matte Case”, check Include, and choose the Case Top and Case Back Shiny objects.  Close the Blackberry group, and add another Matte Element.  Name it “Matte – Phone”, and include the Blackberry group object.  Now clean up the file paths, and disable all the other elements for now.  Turn off Indirect Illumination, turn off both lights, and hide the ground plane.  Render the Matte Element.  When this is done, you can turn everything back on (Fig.27). Please note: We are doing it this way because if you were to do a blanket material override to speed up the render, the TMobile Logo on the phone would not render correctly in the Matte Element.


Step 31:

Go back to Combustion.  Highlight the “Composite” operator, right click and add a new layer. Choose Solid from the type drop down, and set the colour to red.  Drag this layer below the Self Illumination layer (Fig.28).


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