| Rendered Objects on Matte Background Problem
| | | |
Rendered Objects on Matte Background Problem
by scott faulhaber
on
May 8, 2008 at 7:53:10 am
Have a rendered background sequence out of 3ds max that I needed to change the textures on several objects... After re-rendering the objects with updated textures on a matte background and compositing in combustion.... The new objects now have a 1 or 2 pixel outline bleed coming from the original objects in background sequence. I'm still new with combustion...should I use matte control operator with negative values or ???
Any tips or techniques for dealing with this in combustion and/or 3ds max ?
Thanks for any suggestions
Respond to this post Return to posts index
| | | | |
| | | | Re: Rendered Objects on Matte Background Problem
by Kenneth La Rue on May 8, 2008 at 1:45:44 pm
Hi Scott,
Yes you could use a matte operator from the keying tools and enable shrink but first try selecting each layers footage in the workspace panel and then on the Footage control panel at the Source controls turn on “Premultiplied with” option and leave the color to black. You will have to do that for each or the new layers you have rendered. It that does not solve it then use the matte controls operator.
Ken LaRue
Autodesk Application Engineer
Combustion / Toxik / Flame
Combustion Training DVDs
http://www.thestreetproductions.com
Respond to this post Return to posts index | | | | |
| | | | Re: Rendered Objects on Matte Background Problem
by Jeff Brown on May 8, 2008 at 2:11:19 pm
[Kenneth La Rue] "“Premultiplied with” option and leave the color to black."
If your BG color is other than black, it can help to "Premultiply" with the actual BG color from the 3D sequence (depending on how the sequence was saved to begin with).
-jeff
Respond to this post Return to posts index | | | | |
| | | | Re: Rendered Objects on Matte Background Problem
by Eric Craft on May 8, 2008 at 2:32:24 pm
You could also use the RGB Arithmetic operator to replace the or use mathmatic operations between the original and new versions. I have had issues with "Alpha bleeding" do to transfer modes effecting RGBA channels, alpha values adding up as they overlap, etc. So there are various reasons as to why you get the alpha expansion/bleed/inflation effect.
-Eric
Respond to this post Return to posts index | | | | |
| | | | Re: Rendered Objects on Matte Background Problem
by scott faulhaber on May 8, 2008 at 10:46:10 pm
Thanks guys, checking the "premultiplied with" option on new footage has greatly reduced this bleeding effect and gave me an acceptable result.. I'll need to do some reading on this and also will look into the RGB arithmetic and mathematic operations.
Thanks again for the fast help and pointing me into the right direction
Scott
Respond to this post Return to posts index | | | | |
|
|
|
