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« on: 2018-02-22, 20:19:49 »
I've seen this happen very early when S&B was introduced but couldn't nail it down and thought it was an alpha problem. I had a strange dark banding around my objects but somehow worked around it. It's probably safer to stay away from S&B until it's fixed since it corrupts image data. It's particularly bad in compositing apps where working in 32bits is pretty common. I'm surprised no one else has seen this, though.
The issue is probably present with any other color channel, too. Happens in both the plugin (Max in my case) and CIE. Sharpen&Blur is referred to as S&B further in the text.
You can reproduce this with a simple scene, and you even don't have to save 32bits formats. The only thing is to use S&B, and use some level correction in PS to display the problem.
Attached a few images:
• Photoshop_levels_result___without_sharpen&blur_32bits_EXR.PNG - framebuffer saved to EXR without S&B, opened in PS, edit > levels > set gamma to 5 - no problem
• Photoshop_levels_result___with_sharpen&blur_32bits_EXR.PNG - framebuffer saved to EXR with S&B, opened in PS, edit > levels > set gamma to 5 - suddenly these ugly lines appear
• Photoshop_levels_result___with_sharpen&blur_16bits_TIF.PNG - framebuffer saved to 16b TIF with S&B, opened in PS, edit > levels > set gamma to 5 - not a 32b problem it seems, also present in a 16bits TIF
• After_Effects_Inverted_Alpha___without_sharpen&blur.PNG - the EXR without S&B in a After Effect comp (32b) with the gamma channel inverted - no problem
• After_Effects_Inverted_Alpha___with_sharpen&blur.PNG - the EXR with S&B in a After Effect comp (32b) with the gamma channel inverted - it gets bad again
The strange thing is - this does NOT happen in the frame buffer, it seems to happen only for saved output.
I've attached both EXRs - one with S&B and another without - so you can open in PS and check for yourself. A Max 2016 scene is attached, too.
PS. sorry for the disgusting example, got carried away with the material :P