Region Rendering: Minimize difference?

[Lehm]

I've recently started trying out region rendering to get images to render quicker.  However I've noticed that sometimes the regions will render slightly different.  Especially in clouds.  Are there any particular settings that will help minimize this problem?

[domdib]

Could you be more specific? Do you mean crop rendering? If so, then go to the advanced tab in the renderer, in "ray detail region" set this to crop, and set the padding below to at least 1. May not totally cure it, but it's a good first step.

[Oshyan]

This is probably due to differences in the Global Illumination calculations. Similar (though probably more severe) problems are discussed here: http://forums.planetside.co.uk/index.php?topic=6234.0 The Ray Detail Region setting, using the "Detail in Crop region" option, may help. Try a value of 1 to start. You can also try increasing GI Sample Quality (not relative detail) and/or GI Blur Radius (Sample Quality will increase render time). Also make sure Supersample Prepass is on.

- Oshyan

[Matt]

Oshyan, the default setting for Ray Detail Region already is "Detail in Crop Region". "Detail in Camera" is what you'd need if the region looks different when it's rendered cropped, i.e. you make it match the rest of the image by setting it to use the same detail region as the whole image ("in camera").

Lehm, the differences are probably due to Global Illumination. The Ray Detail Region will not help there. Increasing "GI sample quality" on the renderer should improve things, but watch out for how it affects render times and find a value that works for you.

Matt