For years I've wanted to mess around with UV photography. Unfortunately, all the websites on DIY UV seem to assume an infinite amount of money and access to specialized equipment on my part. There are two things that I don't like, when someone tells me I HAVE to spend a lot of money (quartz lenses starting at $3000) or that i need specialized equipment (Wratten 18A filters, not cheap either).
So I set out to do it my way, and here's my $5 solution to UV wavelength photography.
Step 1: Finding a filter
There are two kinds of blacklight bulb (at least), incandescent and fluorescent. I tested both, good for you, because the fluorescent kind DID NOT WORK. This is good because the incandescent is safer to work with, and cheaper.
Step 2: Take your light bulb
Here it is already to mount on my digital camera.