On another thread I am discussing aspects of my film testing experience. As I am about to run the tests again, I would like to ask for any advice regarding the use a small electronic flash unit as a precise source of exposure, to contact print a 31-step Stouffer tablet onto the film I am testing. I would like to explore this option in more detail before I fall-back to using my enlarger, which I would prefer to avoid, due to its longish lamp warm up and start-up times, and the blue/green colour of light (Ilford 500H). At my disposal I have a few units that let me adjust their flash power. I am thinking of using a Nikon SB-800 as it has always performed well, and I have a reliable, and calibrated flash meter, Sekonic L-508, which I have used for the last 12 years. I suppose a studio flash head would be less precise, but I could use it, too.

Please share your experiences of using a flash for this purpose, any gotchas, suggestions and so on. Ideally, I would like to find a fixed position for the flash unit, and a set of relatively fixed parameters, so I could use this set-up for ongoing film testing.

I am also curious about the math of calculating the exposure for this application, though I realise I can arrive at that through additional testing.

Many thanks.

PS. It is hard to find second-hand EG&G sensitometers in Europe.