Try a theaterical supply company for better prices and larger rolls than a photo store. Gaffer's tape comes in a rainbow of colors for color coding wires and cables. I mark lots of things like meters and loupes with bright yellow so I don't leave them behind on a job, it is easy to not see a small black object but yellow stands out. You can tell it from duct tape because it is a cloth tape, not a plastic tape with threads in it like duct tape. If you need somthing even stronger look for military "hundered mile an hour" or "six hundered mile an hour" tapes. It can be used to fix holes in aircraft durring combat.