You can try importing the vido clip into an editor program and then use some digital backlighting tricks. Sometimes those programs have a "quick fix" or "One-touch edit" feature.
You may also try to mess with the gamma (darkest area vs lightest) which will kill the color accuracy but the image's contrast itself will brightened.
I have a few 30 seconds movie clips taken with a canon S1 Is Digital with video capability.I negelected to use enough light in the room and they are hard to view.I know how to correct this with still shots but how can I brighten up a video?
Unreplaceble vids of the grandson at xmas with guitar.

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