saving 8 bit files from the frame buffer in vray 5 issues

[Kirado]

Hi there,

I'm having an issue with the vray 5 frame buffer, after making some colour corrections, when I save an 8bit jpeg file, the gamma curve is not saved into the image.

If an 8-bit file is saved through the VFB or the Render Output / Save image settings, the sRGB gamma curve is embedded and the image appears as in the frame buffer when loaded in an external image viewer. If a 32-bit (exr, hdr, tif) image is saved, it remains linear and relies on the external image viewer to handle the gamma.

Now the strange thing is, it doesn't always do this. Sometimes it saves the curves then out of the blue it stops saving the gamma curves.

Would anyone have any suggestion as to what I may be doing wrong please? I'm not sure if my 3dsmax scenes have different vray settings that are resulting in this, they seem to be the same.

Any help would greatly appreciated.

[hermit.crab]

Note that the VFB gamma curve is preview only, the actual gamma application is done through the set 3ds Max gamma or via a custom override gamma value (both set in the Save Image dialogue). Otherwise, do send some screencaps, illustrating the issue and optimally, a scene where the issue is present so we can take a look.

[Kirado]

Hi Aleksandar,

Thanks for the reply. I'll put together two scenes to illustrate it working/not working

Ideally I'd like to burn in all gamma and colour corrections from the buffer to an 8bit image to avoid going into Photoshop to add the gamma back into the image.

Kind Regards
Richard

[hermit.crab]

You can apply a gamma curve through either the Color Mapping options (mode Color mapping and gamma) or through 3ds max (switch color mapping mode to color mapping (no gamma) to avoid double gamma application) as already mentioned above. Automatic (recommended) means that the gamma value will be taken from the 3ds max preferences.

[Kirado]

Hi Aleksander,

in Scene one, I tried applying the gamma curve through the colour mapping options (mode set to colour mapping and gamma) and the save image still looks different to the buffer

In Scene two, the colour mapping is set to do no nothing, and when I save a jpeg from the buffer it looks the same when opened.