Flickering between frames on different machines.

[fingerindustries]

Hi,

We've got a render farm of 9 machines; all of which have the same version of V-Ray installed (3.00.07) and max (2014).

The problem we're having is that 5 of the 9 machines will render certain bitmaps lighter than the other 4. It seems to happen to texture maps where there is a lot of high frequency detail such as grass or pebbles.

When we view the frames as a sequence there will be a block of 10 frames that look different to the previous 10. I don't recall ever seeing this problem with V-ray 2.

It's happened on a number of different scenes but in general the render settings are something like:

Adaptive.
Irradiance Map and Brute Force.
Embree on.
Linear Colour Mapping.

I've searched the forums and found this thread that sounds like a similar problem, but I don't know if it ever got resolved.


Thanks in advance.

[Svetlozar Draganov]

Can you post a few images in order to see what exactly is the difference?
Have you tried to update to the latest 3.00.08 and run the same test?
Does the issue occur every time or it appears on random basis?
Have you tried to convert all 3DSMax Bitmap nodes to VRayHDRI nodes via the following tool:

[Dmerc]

+1

Just read your post, seems like we have a similar problem . See adjacent post ...

[fingerindustries]

Dmerc, yep that's the one. Looks like the V-Ray HDR map is the place to start short of upgrading to max 2015. I'll do some tests on our files.

For the record here are two frames from an animation which illustrate the problem - put them together in photoshop and you can see it's primarily the hill in the background that's affected.

Thanks for the heads up.

[Svetlozar Draganov]

Dmerc, yep that's the one. Looks like the V-Ray HDR map is the place to start short of upgrading to max 2015. I'll do some tests on our files.

For the record here are two frames from an animation which illustrate the problem - put them together in photoshop and you can see it's primarily the hill in the background that's affected.

Thanks for the heads up.

[ATTACH=CONFIG]21678[/ATTACH][ATTACH=CONFIG]21679[/ATTACH]

Would you please let us know whether the issue disappears if all the textures are loaded via VrayHDRI map instead of Bitmap node?

[fingerindustries]

Hi again,

This is it! Tested a different scene that was also doing it. Loaded the Bitmap vs Vray HDRI in to PDPlayer and it works.

Weird. I think our next upgrade will be to max 2016 rather than 2015, so we'll just have to work around until then.

Do you generally recommend using the VrayHDRI node instead of bitmap nodes even for normal textures?

[Svetlozar Draganov]

Thank you very much for your feedback.
Yes VrayHDRI node is preferable over Bitmap node in general.
It is optimized to save up memory by avoid loading unnecessary textures at the beginning of the rendering and it also supports tiled EXR/TIFF/TX files.

[alexyork]

Does the VRayLog window throw up a warning message if you load an HDR into a bitmap rather than VrayHDRI? Maybe it should.

[Svetlozar Draganov]

I don't think we have a warning for this. Both nodes support HDR images so there is no sense to print any warnings.

[alexyork]

I don't think we have a warning for this. Both nodes support HDR images so there is no sense to print any warnings.

But if using the bitmap loader regularly causes severe issues such as differences between frames and/or excessive memory usage then maybe it should be flagged up as a warning anyway? A "polite reminder" that we might want to use the VrayHDRI loader instead, basically. In the same way that Vray warns if you are using the max bitmap pager.

[vlado]

But if using the bitmap loader regularly causes severe issues such as differences between frames and/or excessive memory usage then maybe it should be flagged up as a warning anyway?

But there have never been issues with differences in older 3ds Max versions - and it is something that should be fixed by Autodesk anyways, maybe it is even fixed in 3ds Max 2015 already.

Best regards,
Vlado

[alexyork]

But there have never been issues with differences in older 3ds Max versions - and it is something that should be fixed by Autodesk anyways, maybe it is even fixed in 3ds Max 2015 already.

Best regards,
Vlado

Ah I see. I've not moved over to 2015 so presumed it was a general max issue.