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arlau
09-18-2004, 11:30 AM
hi everyone, just wondering if anyone has experience comping keyed materials on top of overexposed background. It seems that the superwhite background image would bleed right through the foreground. Another problem is the edge of the matte. Overexposure would probably cause the edge of the foreground to be burnt. But in the comp, it seems that the matte is being choked by the hotspots from the background severely and turn a decent key into something pretty awful.

any advice is appreciated. Thanks very much

jussing
09-20-2004, 10:57 AM
Hi,

can you post screenshots of the two plates?

I don't have the experience you're looking for, so I'm only shooting from the hip here...

Why is the background overexposed? I ask because this is essential to what your foreground element should look like. I think there are two basic scenarios:

1) The background was filmed using too high exposure, which should ALSO make the foreground too highly exposed

2) You're shooting against the light (like taking a picture indoors, of a person up against the window), which should make the foreground plate almost silhouette black.

BLEED:
Yes, I think the background would bleed onto the foreground element either way, but don't do it by changing the matte... composite the shot normally, then apply the background plate again ON TOP, through the INVERSE key matte, and blur that layer, lower opacity, maybe change "mode" to screen or something...

:shrug: Like I said, I'm only guessing. :)

Good luck,
- Jonas

arlau
09-20-2004, 10:01 PM
Sorry, for confidentiality reason, I can't really post the images. But you're right, it's shot indoor and back lit. So the background is supposed to be overexposed for keeping the interior at the right intensity. Unfortunately, the foreground elements can't be a silhouette since the details have to be readible.

Actually, I tried using your suggested method like a light wrap kind of technique for rim lighting. But the edges of the matte is still acting very weird once it got overlaid over the superwhite background. Thanks very much for your tips. I'll keep working on it.

bartrobinson
09-30-2004, 04:42 PM
Perhaps you could elaborate on "matte is still acting very weird" with respect to the light wrap you have applied. Also, I don't know how strict your confidentiality agreement is, but perhaps you could post an extremely cropped image from a frame showing your matte edge before and after composite and with light wrap applied.

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