>>3229251It happens with all single element DIY lenses that I've seen so far. Some are worse than others. The one I made with an actual lens out of an old camera lens has it too (pic), just not as bad as the $5 lens out of the magnifying glass. The brighter things are the worse it gets. It isn't from light bouncing around for these. However, the PVC pipe does have that problem even though it is painted flat black inside. I will probably put in some flocking later on. It also has major light leaks where the groves are for the helical focus. There's 3 grooves and when it is focused on something close, those are wide open to let light in. Though, I don't see evidence of that being a problem. I'm still going to cover them as soon as I figure out a good method to do that.
