Saving to EXR is baking alpha into image and comes with double gamma

[PIXELBOX_SRO]

hi guys,

i ve found a strange difference when saving to VRIMG and EXR (in VFB rollout)
We have a scene with a logo on the black background.
Just for the sake of it, i ve put a black background in the environment slot as a black texture.

Saving to VRIMG is perfect, when opened in PS, is comes with regular gamma and showing the black background.
Saving to EXR 32bit from the same rollout, not only chops off the black color and makes it transparent, but also the rest of the image is double gamma!

Is ther any rule of thumb to prevent this happening when saving to 32 bit EXR from VFB rollout???

What am i doing wrong?

Thanks

Martin

[vlado]

What happens if you view the same files in 3ds Max itself? Which plugin are you using to open the files in Photoshop?

Best regards,
Vlado

[PIXELBOX_SRO]

when view the rendered EXR in material editor, through the vrayHDRI loader, it appears fine, but the material preview itself appears with alpha and wrong gamma (as per attached image)

I saved it as 32bit EXR.
Also the lens effects appear strange.

In PS i use proEXR plugin and it basically does the same thing as u can see in the material editor preview

Thanks Vlado!

[vlado]

Part of the problem is that the lens effects do not change the alpha, they only work on the RGB channel - something that we probably need to address at some point.

The other part of the problem is that the VFB shows the image with sRGB color correction whereas the Bitmap viewer in 3ds Max uses gamma 2.2; the two are very very similar except for very dark parts of the image, like in your case. If you duplicate the VFB image to a 3ds Max bitmap, do you get the same issue?

Best regards,
Vlado

[PIXELBOX_SRO]

I understand the 1st sentence, but I dont knwo what you mean by this:

If you duplicate the VFB image to a 3ds Max bitmap, do you get the same issue?

Do you mean that i shoudl save the VFB to Jpeg and open that in MAT editor?

[Svetlozar Draganov]

There is a button in the VFB which copy the image from VFB into Max Frame Buffer: