Just to confuse you, are you sure it's the same guy? To me the day pic shows an average guy in shorts, a hoodie with a big logo and piping, and sunglasses which are probably not prescription because they're on his head. The night guy stealing the bike is skinny, has long pants, a hoodie with no logo or piping I can see, and appears to be wearing glasses that are most likely prescription. Who wears sunglasses in the dark in unfamiliar yards? Everything he is wearing looks light coloured but might be dark in the day and just reflects IR at night to look bright. My money is on them being two different people. The day guy might be innocent and just cutting through your yard to skip the construction.
As for the CSI stuff, their magic pretty much consists of starting out with great footage, fuzzing it up to make it lousy, and then saying "enhance" or "zoom in and sharpen it up a bit" and showing the process backwards to get to the good stuff from the crap.