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Jazzybob
01-05-2010, 04:22 PM
Hi!

I'm using 3ds max and uses after effects for post production. I wanted to create a Depth of Field effect outside Max, because it takes some serious time. I then add a regular rendered image and a zdepth pass image. Adding lens blur effect and zdepth pass as a depth map layer. Then everything gets blurred nice and smoothly, and you have nice control. But one thing is bugging me, and that is objects that rises up in the air (that has a great distance behind them) gets sharp edges, but the object itself is blurred, but not the outline/ conteour. I've tried several things, also ignored the alpha channels, but nothing seems to help.

Anyone know how to fix this?

jchedley
01-05-2010, 05:55 PM
thats always a bit of a problem with post solutions as far as i know. especially the lens blur/depth channel route inside after effects.

you might try frischlufts Lenscare plugin for a better result (try the demo). it works in a very similar way but is faster and looks nicer.

but extreme changes in depth between occluded objects is always a stumbling block i think.

can you seperate the scene into passes? that would solve it..


(http://www.johnhedley.co.uk)

Mylenium
01-05-2010, 06:51 PM
Anyone know how to fix this?

Yes. Make your depth map and your foreground consistent. The depth map must not contain undefined areas or "breaks" in depth. Empty areas must be filled with the color matching the farthest away point, which may be black, but often is just ta very dark grey. Likewise, pre-compose all foreground and backgroound RGB elements before applying the DOF to get correct edge behavior.

Mylenium

Jazzybob
01-06-2010, 11:17 AM
Thank you for your responses jchedley and Mylenium.
Im not sure I understood all of it though, Im all new to after effects.
precompose foreground and background RGB elements? You mean in after effects or 3DS MAX? I dont know how you do that. I feel I've tried it all.
I attached the files i use below. The zdepth pass and a regular render from 3ds max, plus an overview of my scene from the viewport in max.

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