microfilm or high res low speed film

To be honest these are my first experiances with this kind of films. Resolutions of about 600 - 800 linepairs/millimeter at 1:1000 contrast and a gamma of about 3 in their typical applications are the benchmarks. For regular photography they need to be developed very compensating, often used are special developers. But also high diluted Rodinal can be used, f.e. 1:100 and a very short dev time below 10 minutes.

I was given a big box of long time expired films like Kodak Technical Pan, Kodak Imagelink, Agfa Ortho etc. in 35mm format and the first result with Technical Pan in Rodinal was very promising.for the second try I used Caffenol-C-L and it came out even better. 15 minutes with regular agitation (initially 10 times, then 3 times every minute) at 20 °C and with 0.4 g/l pot bromide, because I read that streaks are a common problem with this kind of films. I exposed at EI 50, but 25 or so maybe would have been better, but I need more data for this rating. As the negs were slightly underexposed, I had to brighten the images a bit in postprocessing, but not too much.

I am very pleased with the results, no fog at all, perfect even development, crystal clear transparent base. The TechPan with the panchromatic sensitation (up to 700 nm) has a nice tonal rendering, the grain is invisible and not resolvable with my scanner, sharpness is extraordinary.  A pity this film is not available from new production. Despite of strong backlight no tonal rendering probs and no halation effect at all, the tiny cables are resolved perfectly against the bright sky even in the distance. That's really something!

If you want to go into high resolution film based photography I recommend that you try Agfa Copex Rapid, that is made by Agfa-Gevaert in Belgium. Drawback is the PET filmbase, so the film must be loaded/unloaded in almost complete darkness. The ESTAR base of TechPan is easy to handle besides a strong ugly curl.

Inportant note: I found that using demineralized water is necessary for the developer and the final rinse and I very gently wipe the wet film, otherwise I get masses of small dots on the film. Treated as described here and the dots are gone completely.

Cheers - Reinhold