Lighting, Translucence
Posted: Thu May 17, 2012 4:58 pm
I'm trying to light a huge envelope of material from the inside. The envelope (think of it as a strangely-shaped balloon) has been resized so that its apparent dimension is about 70" in length.
It's not looking anywhere near what I was hoping for, so perhaps you could give me a few more ideas.
The light source at present is a rectilinear shape, like a very long stretched cube, that runs almost the length of the envelope. I suppose I should just copy the outer skin/envelope, resize it a bit smaller, and place THAT inside the envelope as a light-emitting surface. That would surely take care of slight inconsistencies in lighting (but is not really the big issue).
I've placed a material I've called 0055 Yellow Emitter BOTH on the inside and outside of the envelope surface. I found it didn't really work if the outer surfce were not the same translucent material. I applied the light emitter template and left the power at 100, emitter normal, nothing else changed except that I gave the light a slightly yellowish hue.
EDIT: the envelope material. I left it out! It's based on sketchup's translucent gray and then has a twilight Realistic Glass[Common] material on top of that. Haven't changed much there, though I suppose that's the place where there's greatest hope that changes can move me in the right direction.
I've run it on Easy 09 and Easy 10. Usually only a handful of ray tracing iterations is enough to get a perfectly adequate result. And I'm doing it at lower resolution (849x400 at present) just to see it before committing to a longer run at higher res.
This creates a glassy sort of look which is interesting, but won't serve the ultimate purpose, which is to have this mimic a sort of fabric through which light is shining and ON the surface of which might be colorations in interesting patterns. The goal is to recreate something similar to a night shot of the goodyear blimp such as this: Here is what I've got so far: This is the result of a few days of wrangling! I'd be happy for suggestions.
I'm thinking doing something with the translucence of the surface(s) is the key. Something that isn't glassy but more like the cloth-ish material it is, and I suppose letting rather less light through and diffusing it as it does.
EDIT: I tried changing something with the surface of the envelope, without much luck. I changed the surface to a sketchup solid color (sort of a pale grey) then edited that to make it 80% opacity. Then I applied the twilight template Plastic[flat]. It made things darker which, I suppose, I should have anticipated. --
It's not looking anywhere near what I was hoping for, so perhaps you could give me a few more ideas.
The light source at present is a rectilinear shape, like a very long stretched cube, that runs almost the length of the envelope. I suppose I should just copy the outer skin/envelope, resize it a bit smaller, and place THAT inside the envelope as a light-emitting surface. That would surely take care of slight inconsistencies in lighting (but is not really the big issue).
I've placed a material I've called 0055 Yellow Emitter BOTH on the inside and outside of the envelope surface. I found it didn't really work if the outer surfce were not the same translucent material. I applied the light emitter template and left the power at 100, emitter normal, nothing else changed except that I gave the light a slightly yellowish hue.
EDIT: the envelope material. I left it out! It's based on sketchup's translucent gray and then has a twilight Realistic Glass[Common] material on top of that. Haven't changed much there, though I suppose that's the place where there's greatest hope that changes can move me in the right direction.
I've run it on Easy 09 and Easy 10. Usually only a handful of ray tracing iterations is enough to get a perfectly adequate result. And I'm doing it at lower resolution (849x400 at present) just to see it before committing to a longer run at higher res.
This creates a glassy sort of look which is interesting, but won't serve the ultimate purpose, which is to have this mimic a sort of fabric through which light is shining and ON the surface of which might be colorations in interesting patterns. The goal is to recreate something similar to a night shot of the goodyear blimp such as this: Here is what I've got so far: This is the result of a few days of wrangling! I'd be happy for suggestions.
I'm thinking doing something with the translucence of the surface(s) is the key. Something that isn't glassy but more like the cloth-ish material it is, and I suppose letting rather less light through and diffusing it as it does.
EDIT: I tried changing something with the surface of the envelope, without much luck. I changed the surface to a sketchup solid color (sort of a pale grey) then edited that to make it 80% opacity. Then I applied the twilight template Plastic[flat]. It made things darker which, I suppose, I should have anticipated. --