Quote Originally Posted by Kiwi7475 View Post
Actually reciprocity failure happens both on long and on very short exposures. However modern films only exhibit issues on the short end when the exposure is below ~1/5000 second, most even less than that, so you should be fine with a flash unless you’re using really exotic, very high speed flashes.

This is very technical information thank you! Hope the exposures were ok, shot ten sheets pretty much blind. I did my best!