Color Adjustment is reducing quality of my clip

I abandoned trying to use chroma keying with my green screen
and am now trying to adjust colors to make my clip work (backlit
dancers against green screen and some white wall). I've had
pretty good success with the color adjustment, but when I
do, it lowers the quality of the clip (jagged looking, blurred
and pixelated at edges, etc.).

Does anyone know why this is happening and how I can
prevent it? I'm using FCP 7 on an iMAC. The footage
is 16:9 converted with MPEG Slipstream. Again, the
footage looks fine, it's only when I try to alter color,
saturation, etc. that it looks bad (if I only desaturate,
it looks fine too). But I'm trying to change the greens
to reddish orange (trying to change everything to
that color except black silhouettes of dancers).

I'd be done with the project (book trailer) but this
is stopping me cold. This is the first time I've used
FCP by the way.
Thanks so much for any help!

Cheers,
Robert

Where did the footage come from - what was it originally? What did you convert it to? Green screen becomes more difficult the lower the quality of your footage. If the edges of things get blurry, they become more difficult to separate, because the exact colour begins to vary. Can you get a good key in AE? If not, you may need a better quality original.

(jagged looking, blurred and pixelated at edges, etc.).

sounds like you haven't rendered.


nick

If you are color correcting in fcp you can only go so far. At a certain level of chroma changes fcp is gonna be struggling. Don't get me wrong i have seen some nice results there from some but i would suggest you give Color a try if you have given up on keying.

Both Motion and AE do a much better job at keying than FCP.

How was the green screen lit during the filming?
Dancers move a lot so in most cases that i have filmed them on green screen, I have had 2 things to look out for.

ONE, if my lights were coming from the ceiling then the top would be perfect and the light would get darker towards the floor creating perfect green up top and a darker green at the bottom (like a gradient).

TWO, if i do 4 corner lighting which would be better than situation ONE i might get a darker area in the middle of the green screen. (depends on how wide or tall your Green screen was.

ONE, FCP can not handle but AE can ( as long as the darker area wasn't starting to lean towards a Kelly-like green). There are tolerance issues if it does gets close to Kelly green.

TWO, FCP can handle with the right plugins but the native keyer may not. In this case i would ship to Motion via round trip.

FCP does not key hair well without plugin help. Try Keylight which is a native plugin in AE.

You could even do all of your edits in fcp and then export an XML that could be loaded to AE. Then key away and CC there also if you would like. AE has a mean level curve to get some nice contrast effects.

""" What you do with what you have, is more important than what you could do, with what you don't have."

> > > Knowledge + Action = Wisdom - J. Corbett 1992 """"