Save image with VFB is different from print screen VFB

[Jiri.Matys]

Hello,

just what I said. When I save image (even in 8bit) in VFB, it has little bit different colors from the one I make with print screen and load to PS (it looks exactly the same as original VFB). Where is a problem? Now I have installed latest build of VRay from site and max 2017 SP3.

Thanks.

[crazy homeless guy]

By print screen do you mean screen capture? If so I would be surprised if it wasn't different.

But it could be any number of things causing the difference.... My initial guess would be that you are using a wide gamut monitor and you screen captured image doesn't have a color profile.

Are you trying to do production with a screen capture? Not sure why it is a big deal if they are different.

[dans]

When you save to a low dynamic range 8/16 bits per channel format (e.g. PNG, JPG) then 3ds max will apply the 3ds Max Gamma correction. In your V-ray VFB the sRGB correction used to display the image is slighty different from that. Try the 3ds max Framebuffer - if it now now looks identical to the saved image then you just noticed the Gamma/sRGB difference. If it is something else some example pictures would help.

There are many things interacting here: Photoshop color settings, 3ds max Gamma settings, V-Ray VFB settings, Bitmap format options...

Daniel

[Jiri.Matys]

Yes, I mean screen capture.

Its different even in 32bit. I didnt change anything in color settings - windows is set to srgb, PS is set to srgb, didnt change max or vray.

So I dont get it. And its a big deal, I want picture as I see it in VFB where I do some changes. When I save it, it look worse.

I will try copy it to 3ds max frame buffer or post some screen.

[Jiri.Matys]

I copy it to 3ds max FB and it look different too.
But I try to save it as 32bit vrimg and it looks the same as VFB. Still dont know why 8bit is different, but 32bit looks great now.

And one more question, try to save it as exr, but image is completely wrong, just only mess, never happen this to me, anybody know why this happen?

[crazy homeless guy]

Post screen caps or your image files. It is tough to diagnose without them.

[Morne]

Is it a little different or a lot different? Is it MUCH darker or WASHED out?
A little different could be monitor color profiles. A lot different could be max gamma issues

Instead of print screen, click the image in VFB. Then use Ctrl C to copy the image then go to PS, make a new doc and Ctrl V to paste it in there. How does it look now?

[Syclone1]

Wow I had no idea you could copy and paste from the VFB like that...

Is it a little different or a lot different? Is it MUCH darker or WASHED out?
A little different could be monitor color profiles. A lot different could be max gamma issues

Instead of print screen, click the image in VFB. Then use Ctrl C to copy the image then go to PS, make a new doc and Ctrl V to paste it in there. How does it look now?

[Alex_M]

Hello,

just what I said. When I save image (even in 8bit) in VFB, it has little bit different colors from the one I make with print screen and load to PS (it looks exactly the same as original VFB). Where is a problem? Now I have installed latest build of VRay from site and max 2017 SP3.

Thanks.

The problem is that saving 8-bit image applies gamma 2.2 curve which is not exactly the same as the sRGB curve. It's really close but not 100% the same. You'll mainly see differences in the darker tones which will be a bit washed out when saving 8-bit images. If you need 100% match with VFB, save out to 16-bit/32-bit float formats like EXR or copy the frame buffer image with CTRL+C and paste it in your image editor (PS etc.).

Here's a visual example of the sRGB and Gamma 2.2 curves:

[Jiri.Matys]

Its not 2x gamma problem. Only some colors is little bit different, little bit less saturated I would say.

But new problem with exr is really weird:



First image is jpg, second is exr - complete mess. What is that? No matter what I set in exr, this is what I get.

[Jiri.Matys]

anyone? where is a problem with saving exr please.

[vlado]

I'm not sure where is the problem yet; I'll ask one of the QA guys to look into it.

Best regards,
Vlado

[matanov]

Can you upload that exr here ?

[Jiri.Matys]

Here it is:
https://www.dropbox.com/s/ork43hba0wmghry/test.exr?dl=0

[matanov]

How is this saved and with what settings?