Iray preview no longer works, just for one scene

DefaultName

Hey all. I've been working on a scene for a long time, and, for whatever the reason, it no longer shows the iray preview, not in interactive, or photorealistic. Instead of showing, it just remains in greyscale. I tried saving as a scene subset, unfortunately that has not worked as well.

My old scenes work just fine, as do any new ones. I tried setting the render settings to default, but that also has not worked.

The scene does render though, if I make it do a full render. So I'm stumped.

Anyone have advice? Thank you.

Richard Haseltine

How long have you left it? Does it take a long time to start rendering, or is that fairly quick?