Not sure whether I should post this here or in DIY, but here goes:
I recently built a UV exposure unit out of a series of fluorescent light fixtures (see attached photo). The thing is, I now need to suspend this over any alternative process contact printing I'd be doing (Cyanotypes and Carbon prints). However, I'm unsure what height to set the lights. There's got to be a "sweet spot" region, because if I set the lights too low, I would be too close to the bulbs and get banding across the image, whereas I don't want to set them too high, because of increased exposure times thanks to light intensity falloff. (Also, it would be a chore to move). Does anyone have any suggestions as to how to determine the height at which I should set these bulbs?
The bulbs are F15T8 unfiltered blacklight bulbs, if that makes a difference.