Hello AbsoluteRyan, and welcome to the friendly Camera Labs forum!
To enjoy your stay here please have a look at the
house-rules!
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Imho a room 13 feet long is too short for capturing full body-shots of a standing person. You have to subtract the necessary distance of the person in front of the background and you yourself need at least 1m "wiggle-room" behind the tripod. So you get max 2 meter operating distance between your lens and the subject
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Thomas (beware: Nikon-fanboy and moderator!)
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