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RogerRyan
02-19-2008, 10:14 AM
I am working on a personal project of a bedroom and running into difficulty with creating daylight. I am using GI with FG and photons are coming out blotted. Can anyone help me with creating this daylight with the right amount of photons + GI intensity. The sunlight will be coming into the window of the room. I have been reading 'Digital lighting & Rendering' 2/E, and things have not been turning out right. Please help!

Thank you:):wise::shrug:

Here's a link to the scene
http://forums.cgsociety.org/showthread.php?f=43&t=595972
frizDog
02-19-2008, 04:32 PM
It will be hard to comment on specific photon settings as it is scene dependent and you will have to dial those in yourself. If its 'blotted' that usually beans not enough photons.
Even with GI renders you will need to add a spot light to create the intensity of the sun. Especially for a brightly lit daytime scene. Dial that light positing intensity in first with ray traced shadows, then turn on your GI and dial that in. Think of your GI/fg pass as the bouncelight,abmitent light in your setup.

post some rendered images so we can help with specifics
RogerRyan
02-20-2008, 11:54 AM
Things have been getting better but the light still is not right. I used a spot light near the window (for the sun) and an area light (for the skylight). All images have GI+FG enabled.
frizDog
02-20-2008, 04:31 PM
It doesn't look like you have shadows enabled. . .
Without knowing what software youre using its hard to know what switches to put...
I would find a tutorial and follow the steps in them to see if you get a better result
RogerRyan
02-21-2008, 04:21 AM
The software I am using is Maya+ mental ray. I have also found some tutorials on GI and FG.
I will also check on the shadows.

One question I have is:
Does any lights need to be in the room when using GI+FG? Or just skylight and sun Thanks.
Sully
02-27-2008, 02:30 PM
If you are using GI you will need to have at least one spot light emitting photons in the scene, for more information have a look at this (http://forums.cgsociety.org/showthread.php?f=87&t=190232&page=41&pp=15&highlight=gamma) thread where you will learn all you need to know.
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