Integrating 3D models with photography
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# 1 17-03-2013 , 07:02 PM
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Ambient_Occlusion_Render_Not_Shadowing_PillowRuffl es

Unfortunately, the pillow here is not showing the details of the edge "ruffles" via the ambient occlusion rendering. I thought it was the way I set up the UVs so I have included an image of them. If it is the UVs what can I do to correct them to show the detail of the wrinkles at the edge of the pillow? If it is not the UVs then what can I do to get Mental Ray show the detail via the AO? Any suggestions would be much appreciated. user added image

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# 2 17-03-2013 , 07:23 PM
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Could we have a bigger shot of the render............dave

Edit:if that is your UVs they should be inside the top right box of UV space




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Last edited by daverave; 17-03-2013 at 07:27 PM.
# 3 17-03-2013 , 08:14 PM
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I don't think AO is reliant on UVs. AO is typically used to shadow tight corner regions, hence occluding ambient light. But perhaps the ruffles aren't defined enough to occlude any light. Either way, try playing with the max distance and spread in the AO settings to see if you can get some shadowing.

# 4 17-03-2013 , 08:30 PM
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Dave,

Yes, those are my UVs. I will move them to the top right half of the box, thank you for the suggestion. Here is the larger AO rendering as you asked for.

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# 5 17-03-2013 , 08:52 PM
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Put a plane under it and turn on reflection in the occlusion setting.............dave

Edit:I was in a rush so did not see what Stwert said he could also be right




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Last edited by daverave; 17-03-2013 at 09:26 PM.
# 6 17-03-2013 , 09:59 PM
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Thank you! Adjusting the attribute setting and adding a plane made a huge difference in the result of the AO. Not to be obtuse but would you mind sharing a bit of the theory behind why this works? Also, now the "corners" of the body of the pillow are showing up as hard-ish edges. Should I add more divisions to the poly or is there an AO attribute I can adjust to remedy this development?

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# 7 17-03-2013 , 11:05 PM
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Can I ask what the purpose of the render is? If you are multiplying this over another render, you can reduce the opacity and the edges shouldn't show up as strong. You can also increase the samples, and try normals > soften edge, but I don't think AO looks at hard/soft normals either... could be wrong. Sorry dave will have to explain the plane, that's a new one for me.

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