Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: tom182 on 2022-05-06, 12:08:09

Title: corona8 frame buiffer, darker
Post by: tom182 on 2022-05-06, 12:08:09
Hi,
I seen to have a prob,
just started with Corona R8, and getting darker images than expected when i open in PS. gamma enables and set to 2.2 (reminds me of  the horrible vray days)
I render and save as png, > i open in PS then image is darker than the corona frame buffer image.
this wasnt happening in R6 (I skipped R7 )
any ideas?
Thanks
T

Title: Re: corona8 frame buiffer, darker
Post by: TomG on 2022-05-06, 13:32:15
What Color Settings are you using in Photoshop? (Edit -> Color Settings), in particular Working Spaces and Color Management Policies.
Title: Re: corona8 frame buiffer, darker
Post by: tom182 on 2022-05-06, 13:58:08
as per yours Tom, with the exception of a checked box for 'Compensate for Scene -referred profiles'

So if i save straight out as a png from the FB it will be dark in ps,
if I save as a cxr and then as a png it will be corect in PS but even with alpha split option ticked in the save options dialog the environment (corona sky with ground) I cannot load slection without the entire image being selected, i.e. object  and background not sepatated, what am i missing??? i havent had this issue in previous versions, I can upload scene if that helps,
Thanks,
Title: Re: corona8 frame buiffer, darker
Post by: TomG on 2022-05-06, 16:18:12
Scene, and screengrabs (so we can see how it looks in the VFB) and image (so we can try loading it into PS), could be useful (though someone may recognize this issue even without those).
Title: Re: corona8 frame buiffer, darker
Post by: tom182 on 2022-05-06, 17:35:59
ok stripped down scene, but same issue of diff between vbf and opening PNG in PS

hopefully this will help to see whats up with my scene.

thanks
Title: Re: corona8 frame buiffer, darker
Post by: TomG on 2022-05-06, 17:45:49
Your Bitmap Files Output Gamma is 1.0, and not 2.2, see this warning I get on opening the scene:
Title: Re: corona8 frame buiffer, darker
Post by: tom182 on 2022-05-06, 21:41:34
only when i restarted max that I saw that dialog,
wierd thing was that this was a scene from earlier Corona R6 that was rendering out fine, but gamma output changed after R8 or something else caused it that I am unaware of.

So i save out image at 2.2 from VFB. Thats what it should be at correct? or can i have it set to 2.2 automatically?

I have outputgamma @2.2 in currentdefault.ini file so presumed that took care of the bitmap output gamma

cheers
Title: Re: corona8 frame buiffer, darker
Post by: TomG on 2022-05-06, 22:12:35
So as far as I can see, versions of Max newer than 2014 do not offer separate controls for input and output gamma, and it's all covered in https://support.chaos.com/hc/en-us/articles/4528480099345-How-to-configure-gamma-for-rendering-

Based on that, this scene must have been saved from 2014 with incorrect Output Gamma, or saved from a Max with an incorrect .ini file that had the output gamma entry set to 1.0. The swap in versions of Corona won't have changed anything, since these are all Max settings, and must come from a different version of Max rather than an update to Corona. Hope that helps!