Need help to correct Corona Exposure

[Byteman3D]

I'm rendering two versions of an animation project, parts of which are quite the same. I have rendered version one entirely, and I was planning to render the different plans of the version two only and get the rest from version one. Unfortunately I have rendered the first version with exposure set to -0.5 while left the second version 0 as default.

Now I need to correct the exposure of one of the frame sets to match the other. I can try to match by trial and error but I wonder if anyone can tell me the exact value of a certain exposure workflow which will match this 0.5 eV shift in Corona?

[TomG]

The main question is, did you save to a format that supports HDR? Like EXR, or PNG with enough bit depth? If it was just JPG or straight to an animation format, then you can't adjust exposure in post and would need to re-render :(

[Byteman3D]

Unfortunately PNG without that much bit depth, but I guess a certain brightness value addition should help match approximately without perceivable difference.