I'm in the process of trying to make a specific light source with one of my strobes. I need a light that produces a thin wide band of light for lighting a model. So - I took one of my strobes, put a cardboard tube on it about 2 feet long with a cover on the end with a very narrow slit in it expecting to get a narrow band of light. Instead, when I fired the flash, I got a perfect reversed image of the flash tube in my strobe! Duh, it took a while for it to finally sink in that all I had created was a version of a pinhole camera. So - any ideas on how to pull this off. The light source can as close as about 3' away from the model and the light band needs to be about 1" tall by about 12" wide. A simple version is the sun shining through the blinds on a window, but that won't work with the studio type of set up that I have.