V-Ray RT production rendering settings

[bvdsdesign]

I've got a Titan X in one workstation and GTX980Ti on another for some weeks now. To realize that I wasn't using Vray in a correct way:
I was still using Vray advanced (CPU) instead of V-Ray RT as a production renderer. No wonder I didn't see any change ..
So my question is what should I use? Engine Type CUDA or OpenCL,...
And what are good settings to use?
Are there any negative points using GPU rendering?
Any tutorials available regarding V-Ray RT as production rendering?

Thanks

[vlado]

If you have nVidia GPUs, then go with CUDA.

Good settings are the defaults Just enable GI and you are mostly ready to go. You might have to adjust the sampling settings for render time, or number of passes, but that's pretty much it.

Negative points are the limited amount of GPU RAM, and the things that are not supported on the GPU. There are less and less of those from one V-Ray release to the next, but you have to evaluate if there is something missing that is needed for your workflow.

Best regards,
Vlado

[bvdsdesign]

Hi Vlado,
Thanks for the reply. I did like you wrote. Just change the engine type to CUDA, but the resulting image is really different:
CPU GPU
Forest Pack default items seems ok
Vray Dome + HDRI is ok
Vray Textures are way of for some reason
Vray plane doesn't show
And some textures from the imported DAZ figure seem to be off also.

What can I do about this?
Also when rendering in GPU I really don't know when the rendering is finished..

[vlado]

You can specify if you want the rendering to finish after a certain amount of samples, or after a certain amount of time, or when a specific noise threshold is reached - it's up to you.

Support for VRayPlane is added for the next service pack. In the meantime you can just use a large regular plane.

The bump map on the water is probably noise and we don't yet support procedural textures for bump mapping on the GPU (the Noise works for colors though). You could try using a bitmap noise.

Finally, are you using a Tiles map for the pool itself?

Best regards,
Vlado

[bvdsdesign]

Hi Vlado,
First of all to be clear this is just a little test scene combining multiple models (dwg,daz,itoo..)
The tiles texture are made with tile maps. What about the rescaling of some textures (daz figure)?
My objective is to have a workflow that is faster using the potential of the GPU.
Are there any other way of using CUDA within vray, as it seems RT doesn't support everything yet.

[vlado]

The tiles texture are made with tile maps. What about the rescaling of some textures (daz figure)?

There is an option to rescale textures for the GPU; it is enabled by default.

Are there any other way of using CUDA within vray, as it seems RT doesn't support everything yet.

Nope. I don't know if there will ever be a time when the GPU renderer supports everything from the regular V-Ray, so don't wait for that time. You can still do a lot of things with what we do support on the GPU, and of course we are adding more and more things with each service pack. Some users have actually completely moved to GPU rendering.

Best regards,
Vlado