Render Region to PV?

[rodross]

Is there a way to actually render region in a finished manner? I didn't see any way in the manual. I have some water that is creating really horrible dancing grain, but it's only about 20% or less of the image. I don't want to up the samples for the whole frame, for the whole 300 frame animation, and lose a ton of extra time when I could maybe just up samples in one material, or do a separate render of that region with high samples.

[aoktar]

hi,
there is a problem with render region on picture viewer. First frame is done full, next frames will be under render region. I'll fix this soon. Tryed to describe usage. Parameters are animatable over frames

[rodross]

Ah, ok, thanks Ahmet!

[rodross]

Ok, so using RR seems to divide the sample count. I seem to get all the samples in the region in the LV, but in the PV instead of 2048 samples, I get 447. So the first image, like you said, renders the FULL image, but only the region gets full 2048 samples, then the next frame is just the region, and only gets 447 samples and is grainier than the first frame. So I think this may need to be addressed as a bug? I can't imagine rendering a region for compositing and not even getting the original quality of the render you're trying to fix.

I know you said you may need to up the samples, but if you're trying to match a render, but just change the color of a small part of it and end up with more grain or less samples or more samples and they don't match, then what good is RR? Do I need to come up with a formula to figure out how many samples the region needs to be to be at least equal to the other render?

[rodross]

Here's a frame 1 and 2 comparison.

[aoktar]

yes, it's same issue. There is a problem on algoritm for first frame. Start a full frame, then activates region in first frame. So this is reason to see pixellated area on out of region. This is for first frame.

For samples, this is not a mistake. Plugin does a estimation on maxsamples to match full frame noise ratio. So if you set 2048, it will not goes to 2048. It calculates new maxsamples value. I think first frame made you confused.

[rodross]

Yes, the first frame seems to have ran more samples into just the region render area, then not as many in the same area on the next frame. I did compare a full render with a region render and the grain seems to be pretty much the same. Thanks.