Lens effects make renders very dark

[Alex_M]

Something strange started happening with lens effects that I don't think happened before installing Vray 3.30. When I load images from the History panel that were rendered with lens effects, they get darker a second after I load them. Please check the images below. At the left is the image how it's supposed to look and to the right is how the image looks a second after it's loaded from History. If I render the images from scratch, there's no such problem. It's only when I load the renders from history when this darkening happens. Any help is appreciated.

[tashko.zashev]

Actually we just fixed an issue that looks very similar to the one you are facing now.

http://forums.chaosgroup.com/showthr...=bloom+element
http://forums.chaosgroup.com/showthr...+effects+gamma

Probably it's the same thing, but we will need a scene to confirm that.

[Alex_M]

Looks like a similar problem, yes. Please find attached the scene from my example. I've stripped it of almost every object except for the walls, floor windows etc. I hope this doesn't affect testing.

lens_effects_derkening.zip

[tashko.zashev]

Thank you for uploading the scene file Alex.
This is a different issue related to the color mapping/exposure settings and V-Ray lens effects. When loading an image from the VFB history and Lens effects (bloom or glare) are enabled the image is being color corrected again with the exposure settings used for the last render. Hope we can fix it soon.

[Alex_M]

Great to hear that you've pinpointed the problem. Is there a workaround until the fix is implemented?

[tashko.zashev]

The workaround should be to match or use the same camera exposure for the scene where the image is loaded. Otherwise this image loaded from the history will be color corrected using the default camera settings. I will search for more convenient way anyway.

[Alex_M]

Got it, thanks!

[andy_butler_7]

Just to check , is this fix in the latest build of VRay 3.30.04? I sent a render with bloom and glare on before I knew of this issue and it has come out darker that it should have. Which is the opposite of the previous posters problem. But I have checked it after reading this and when I turn bloom and glare off, my VFB returns the correct colours.

Cheers.

[tashko.zashev]

Just to check , is this fix in the latest build of VRay 3.30.04? I sent a render with bloom and glare on before I knew of this issue and it has come out darker that it should have. Which is the opposite of the previous posters problem. But I have checked it after reading this and when I turn bloom and glare off, my VFB returns the correct colours.

Cheers.

Yes, it is fixed in 3.30.04. But if you still experience any Lens Effects issues with that build please send us your scene file to support@chaosgroup.com

[andy_butler_7]

I re-sent again last night and the only problem (although I'm not blaming VRay as I'm not sure if it's the cause) is the bloom and glare elements did not save. I am tile rendering through Deadline and just to complicate it even more, sending the renders through RPManager.

Are there any known issues with the elements not saving when tile rendering? the reason I ask is because I can't add the Bloom and Glare elements in to my elements list, so I wonder if they don't get saved because they are not in the list.

There are on in the VRay frame buffer though. Any thoughts?

[vlado]

Are you rendering to tiled .vrimg or .exr?

Best regards,
Vlado

[andy_butler_7]

No I'm rendering to tiled .tiff 16-Bit.

[tashko.zashev]

Hi Andy,

I don't have RPManager here to perform a test with the same configuration, but I did one using Deadline tile rendering and Lens Bloom and Glare (VFB lens set to render elements only) was saved successfully.

The problem might be in the RPManager setup, so please try to run a test without it.

My setup is / Max 2016 / V-Ray 3.3 / Deadline 7 /
The job was submitted through 3DS Max Deadline submission script and VFB Separate render channel was used to output the TIF files and all render elements.
If I've missed something from your steps please let me know and will start another render job.

[Alex_M]

I just installed Vray 3.30.04 hoping that it will work fine now but I'm sad to report that I'm still having the same issue - dark renders. Please see below.

[tashko.zashev]

Hi Alex,
Can we get the scene file for this issue ?
Is that a regular render in 3DS Max UI ?