Gary, the only numbers on the unit refer to the angle for bounce. I wish it had a dial or reference scale. I made a note somewhere that suggested the guide number is 160. If that means f16 at 10 feet for ASA100 film, I am then trying to figure the settings for ASA 400 film. I suspect they would be a 2 stop difference, f32 at 10 feet. Unfortunately, my camera syncs at 1/60 and my 50mm. lens only goes to F16, so it may be too strong for ASA400. Any thoughts?

I have not used the flash enough to know how to work with it. I need to record my classroom for my master's project, so I have got to force myself to use it. I may have to resort to the old Vivitar 2000.

Thanks for your feedback guys.