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We have a glass object falling and shattering into many shards. Unfortunately the green screen was uneven causing different shadings on the background.

Our edior says to use the shot, he would have to rotoscope all the frames which is not practical on our budget for our short film. It is a very important shot.

Is there an alternative way of removing all of the green screen by computer by screening out a range shades of green?

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  • What application are you editing in? (Or which apps do you have access to?) – user1118321 Jun 2 '17 at 1:45
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    A screen-grab of the footage or a sample clip would be helpful too. – stib Jun 2 '17 at 3:01
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If the example were a lightbulb at the top dropping to the bottom you would take one frame with the bulb at the top and one frame with the bulb at the bottom, then simply use half of each as a mask.

Choosing a range of colors is also possible if it's not so wide as to reduce the remaining.

Movement detection is also possible.

Where this would be really tough is a moving camera and a light colored Green Screen that was poorly lit with a darker green object that moved slightly and rotated in one spot - better to use a red or blue screen in that case.

Here's a manual and automatic Photoshop technique example: https://phlearn.com/tutorial/automatically-remove-objects-photos-photoshop/ .

Uploading the Video to YT as unlisted would allow us to give a more precise answer than guessing the situation and providing a general answer.

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I don't even see how rotoscoping would help and can't think of a way to solve the issue directly with the green screen footage (if I understand the situation correctly anyway). If the glass is transparent, it is going to cause further distortions and the green screen itself is going to impact the color of the glass. That alteration to the color would still be there after green screening.

This sounds like something that should be done on a matte black background and luma keyed rather than chroma keyed on green. You'd get better information about the transparency of the glass then.

Alternately, the easiest way would be just to simulate the object entirely in CG. You can make really realistic glass objects pretty easily using the video itself as an environment and get something that works better than either a chroma or luma key is likely to work.

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