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Chroma Key Channel Issues
Hey,
I recently spot something with a very well-lit and even green screen and am in post working on the keying elements of this video. We shot it on a Panasonic SDX-900 with a huge green screen, lots of Kinos and other lights, etc.
Prior to pulling a key, I wanted to look at my channels to make certain that I can pull a good key. I am noticing that the red has a little noise in it (which is fine), the green is perfect (as to be expected) but the blue channel is causing me to have a tremendous headache! This channel is extremely noisy and my subject is wearing jeans. This is causing some noisy pixel around the bottoms of his pant legs.
I have already tried to combine channels, shift channels and set channels and nothing seems to work well in getting rid of this noise. Can someone please help me understand the best way in softening this noise prior to pulling the key? I really appreciate any and all advice. Thanks.
Seth
Opportunity is missed by most people because it is dressed in overalls and looks like work.
Thomas A. Edison -
5 Replies
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for some reason the blue channel is often noisier than others… you may be able to apply a slight blur to the blue using the channel blur effect to help.
Kevin Camp
Designer – KCPQ, KMYQ & KRCW -
Thanks Kevin.
Yeah, I know the blue is always noisier than any other channel and I have really not seen something this noisy since I started in this industry and was shooting on crappy mini-dv. I was hoping the SDX in DVCPro50 mode would work better. It significantly did but the blue is still more noisy than I would like. I will give your idea a shot. I appreciate it!
Seth
Opportunity is missed by most people because it is dressed in overalls and looks like work.
Thomas A. Edison -
there is also the ae preset called reduce dv blockiness, which does a typical trick for chroma smoothing of dv prior to keying… (channel combiner, rgb-yuv; channel blur g & b; channel combiner, yuv-rgb)
Kevin Camp
Designer – KCPQ, KMYQ & KRCW -
Kevin,
I saw that and that’s what I was really going for here. However, when I preview out on my broadcast monitor, I am getting a lot of schmutz around my principals face as well as in his jeans. So, I have decided to key the whole thing (primary matte, core matte, edge matte and light wrap) in Shake. Thanks for the tip. I will have to try something else in AE when I am not on such tight deadline. I really appreciate your input here.
Seth
Opportunity is missed by most people because it is dressed in overalls and looks like work.
Thomas A. Edison -
hey,
i want to know that how to remove chroma without using keying and keyling or any other key. use only channels. how can remove the chroma using only channels.
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