Render elements don't add up to RGB result when using burn value for Reinhard mapping

[kosso_olli]

I have a small problem here. I rendered a rim for a car where I used the burn value in the Reinhard color mapping settings to reduce the burnt out areas. The problem now is that I can't get my renderelements to add up to the rgb result. The layered version is a little brighter. I fiddled around with the color mapping checkbox in the render element section, but that didn't help. The renders were saved as .exr. Am I missing something?



Regards

Oliver

[Pixelcon]

I think this is just how it works. Compositing has to be in a linear format and by changing the burn value from 1, you're changing the image to a non-linear format.

If you render with 32-bit you can emulate the burn value decrease with a curves adjustment in your compositing app.

[kosso_olli]

Okay. I am not sure but I could swear that it worked back in 2.4.
Also, the image is rendering in nearly half the time when using the burn value. Seems the sampler has an easier job that way.

[kosso_olli]

Now, is this behavior expected or am I doing something wrong?

EDIT: Tested it with color mapping set to HSV Exponential, with dark and bright multipliers set to 1. The problem is the same, I can't get the correct result with layering the renderelements.

[Svetlozar Draganov]

Have you tested it with color mapping set to Linear / dark multiplier 1 / white multiplier 1 / gamma 2.2 ?
If that doesn't work then there is something wrong. Are all materials in the scene Vray materials?
What application you are using from compositing? In what bit depth are the outputted files?

[vlado]

Okay. I am not sure but I could swear that it worked back in 2.4.

No, it didn't work either. (How can you swear about it if you are not sure )

Also, the image is rendering in nearly half the time when using the burn value.

Then set the color mapping mode to "None". You will keep the render times, but you'll get a linear image out in the end.

Best regards,
Vlado

[kosso_olli]

No, it didn't work either. (How can you swear about it if you are not sure )

Then set the color mapping mode to "None". You will keep the render times, but you'll get a linear image out in the end.

Best regards,
Vlado

That's true, checked it with 2.4 this morning, it didn't work. Don't know what I was thinking of...
Will revert to linear color mapping and default multipliers and find a way to reduce the burnt out areas.

Regards

Oliver