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maco
08-23-2011, 01:34 PM
I want to tonemap an image in post but get a problem when I batch render with mr to a 32bit image. I get aliasing where bright light meets darker areas.

Here is a image to display the problem. View i full size to see better.

http://img11.imageshack.us/img11/7117/aliasing.th.jpg (http://imageshack.us/photo/my-images/11/aliasing.jpg/)

I use physical sun and sky with a portal light, no lens shader on the camera, everything gamma corrected, framebuffer set to gamma 1 and data type 32 bit float(also tried 16 bit half)
Tried diffrent tonemapping softwares and they all display the same alisaing.

Saw this old thread which seems to be about the same problem but i donīt really find the solution to my problem while reading through it.
http://forums.cgsociety.org/showthread.php?t=228917

Hope there is a simple solution to this problem.

/Marcus
djx
08-23-2011, 02:20 PM
This is a limitation of doing the tone mapping after the antialiassing. If tone-mapping does not allow you to reduce the overbrights enough to smooth things out, then you can try adding a blooming effect to mask the jaggies. This blooming is similar to what would happen in a digital camera and can look quite effective.

David
Ekenryd
08-23-2011, 02:42 PM
David, do you have any tips on how to do blooming like that in post? What I can think of right now is duplicating beauty in photoshop, caping the color data at a very high level, so that only the brightest parts remain and then blur them. Although this way I think there still might be some jaggies showing through the beauty layer. Do you have a more efficient way to recommend?
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