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View Full Version : how to control exposure?

ywmang
07-05-2002, 03:33 AM
hi,
I use the Viz 4's automatic exposure setting to control the light level of the scene. The problem is when I change anything in the scene, say take away an object or remove a light, the overall brightness of the rendered image changes. It makes so much trouble when I composite the image in photoshop, like making corrections..... because the brightness/contrast are not the same!

Does anyone know how to solve this?
Is there any way to fix the exposure value?
TheDevil[DK]
07-05-2002, 01:41 PM
hehe... the auto exposure is a killer... do the lightning good and fix the exposure problems in PS
ywmang
07-06-2002, 05:03 PM
just in some case I can't avoid using the auto-exposure, like I have same set of interior lights for day scene and night scene.
in the day scene the interior light level is insignificant when compared with the sunlight. (but somehow i can't turn them off, or the interior will be completely dark!)
but if the same level of interior light amount is used in the night scene, the outcome will be a completely dark image, can't see anything at all. Here's where I need exposure control.
Everything would be fine for me IF the exposure is not automatic.

Just because the it's an AUTOMATIC exposure, when I ever change anything in the scene, the overall brightness/contrast of the rendering will be changed. That makes a lot of trouble when I try to correct a small part of a previous rendering by render region. The little piece of re-render region usually won't fit into the previous because of different brightness!

This is my problem........

does anyone have any advice?
24mm
07-06-2002, 05:12 PM
Hey, I really want to solve your problem. But I need to know what exposure and aperture is. Any information or a link will be useful. And thanks, I think you can make it. Just think on it more.
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