opencv Background Subtractor

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I'm trying to use Background Subtractor to try and extract a moving hand in a background. However, a problem I have when trying to extract my hands are that there are these black blotches found within my hand which are not helpful at all. Even with a non moving background I still find this occurring. I want to the best of my ability as much as possible have a majority of my hand included that can make out or distinguish my hand from the background without these noticble blotches. here's an example of one which I just took

Just to clarify, What im intending to do with this is to use it for a mask to extract the hand shortly after.