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Re: Backlit Rice paper
Posted: Thu Mar 19, 2015 3:12 pm
by dotcommer
Yeah, I've tried camera visibility tags already, both in octane and C4D tags. I think the issue is its just a ton of light being emitted and being reflected in such a small space. I don't have any specular or reflections on this texture though so I don't know how to reduce the glare any other way. I'm not sure if I need to look into another way to produce this backlit effect. Maybe SSS instead of just a transmission texture? I don't know yet, but its killing me because it is looking really good, just when you look at it from any angle other than dead on, you get that terrible hot spot.
Thanks for the suggestion though!
Re: Backlit Rice paper
Posted: Thu Mar 19, 2015 3:32 pm
by tomabobu
Can you post the scene so I can try to find a solution?
Re: Backlit Rice paper
Posted: Thu Mar 19, 2015 3:55 pm
by dotcommer
tomabobu wrote:Can you post the scene so I can try to find a solution?
Certainly. Unfortunately I'm away from my computer today. But later tonight I'll upload it (was planning to share the scene anyway once I got the look down).
Re: Backlit Rice paper
Posted: Thu Mar 19, 2015 5:33 pm
by dotcommer
We're in luck! I was able to remote access my comp and upload the scene file. Take a look.
http://www.deltawavefx.com/uploads/back ... e_test.zip
Re: Backlit Rice paper
Posted: Fri Mar 20, 2015 4:06 pm
by tomabobu
No luck. I couldn't get the light from one side to be transmitted on the other side without attenuation. The rice paper is so thin that the amount of light on one side is very close in value to the amount on the other side.
See the attached, fake solution, that doubles the paper geometry to darken the diffuse on the interior.
Re: Backlit Rice paper
Posted: Fri Mar 20, 2015 5:13 pm
by aoktar
Your dimensions are looking very big. You should work on real world sizes to get more realistic results. See my tests
Re: Backlit Rice paper
Posted: Sat Mar 21, 2015 2:09 am
by dotcommer
Ahmet, your test looks to be the same size as my lantern. And it has the same issue as mine: blown out on the inside. I'm not understanding what your test file is showing. Do you mean project scale? I'm working in centimeters right now.
Do you think SSS on the paper texture might give me a better result? Maybe letting more light through the paper without having to increase the light source intensity so much?
Re: Backlit Rice paper
Posted: Sat Mar 21, 2015 2:29 am
by aoktar
dotcommer wrote:Ahmet, your test looks to be the same size as my lantern. And it has the same issue as mine: blown out on the inside. I'm not understanding what your test file is showing. Do you mean project scale? I'm working in centimeters right now.
Do you think SSS on the paper texture might give me a better result? Maybe letting more light through the paper without having to increase the light source intensity so much?
your lantern's dimension was about 3 meters. I thought that should be problem. In my tests, i see the light source gives good effect on flat surfaces as in your example images. But on spherical geometry, illumination is more homogen. Wished effect is more visible only when light source is more close to surface.
Re: Backlit Rice paper
Posted: Sat Mar 21, 2015 5:16 am
by dotcommer
–
SUCCESS!
Tom, you were almost there with your test. You just needed to increase the brightness, and add an Octane object tag to the interior pieces and set the visibility down a little. Aw man, this is great! I'm going to have some fun with this lantern now that I've got the look down. Tomabobu, thank you so much for your help on this! It renders really fast too. Just need about 200 samples and its clean! I was able to get a single frame of this lantern rendered in about 20 seconds. Not bad!
I'm uploading the "final" project files for this lantern so others can download and experiment with it, as a thank you to this awesome forum! Thanks to everyone who helped out with this!
_
Re: Backlit Rice paper [SOLVED] [PROJECT FILE]
Posted: Sat Mar 21, 2015 7:40 am
by ten
Nice one DC. Thanks for sharing the results. Will help the rest of us out in a similar situation!
ten