Projector - any ideas?

[colorlabs]

Hi, I'd like to simulate a projector in Octane. My first thought was an emitter plane covered with a film plane which has the projected image as a transparency map. But of course, this just results in a blurry mess being projected.

(pic above is 3 planes - emitter at bottom facing up, film, and screen at top)

Perhaps I could create a VERY long tube to make a VERY narrow spotlight...then put the film at the opening to the tube.

Any ideas? Anyone ever done this with an unbiased renderer?

[trofaster]

I've done it, making gobos for an interior light project. The narrow spotlight approach worked for me, but i'm sad to say that I could only get it to work in maxwell - in Octane i had to crank up the exposure so high that colours started acting weird.

/rune

[colorlabs]

Well, here's the best I could do...here's 64k samples

attempting to project this image:

oh well, maybe someday I'll give it a shot again.

[Miguel Lescano]

Mmm... yes, I've done it with Twilight's unbiased engine. I believe Thea Render can do it, too.

I'm new to Octane -just bought a license- and I'm wondering why it should be so difficult to do. I guess the current version of Octane doesn't have spotlights, which in other software can load an image to project.

[colorlabs]

Yes and one of the Octane developers implied once that spotlights will never be implemented because they look unnatural and would slow down rendering.