different shadows in preview and render ??

[fferro]

Left side shows a render (Full Render). Right side the viewport.
The heighfield is a DEM file. No clouds.
Shadows looks better in viewport. Render shows the sun in a lower position. Why?
Thanks

[PG]

This has already been spotted a couple of days ago. The preview window takes a number of shortcuts, including the GI prepass (which it prepasses fnarr fnarr) for performance purposes. So for now you shouldn't rely too heavily on the preview for lighting, just for terrain, shaders, that kind of thing. Matt said he's looking into a better way for an update after the release.

[neuspadrin]

Yep, lighting and gi is the big hit on rendering generally, so the shortcuts are taken to make the preview render go nice and quick.

[rcallicotte]

The preview is done in OpenGL and the differences are more controlled in the render through your settings - GI, shadows, Environmental Lighting, Clouds, etc.

[Oshyan]

OpenGL is only used to *display* the results of the render preview, it is not used to actually render it, so it has virtually no effect on the render quality.

The differences between the preview and final render do come down to detail and certain "shortcuts" taken to make the 3D preview reasonably fast. You will also notice less significant differences between detail levels in normal renders though. That's essentially what increasing detail does - it increases accuracy, which will of course change the result (though hopefully not significantly, and of course for the better, keeping in mind that "better" is somewhat subjective).

- Oshyan