FilmHolders vs Silverlog Flash

The FilmHolders App allows to store the status of your large format film holders. It is a one purpose application which does not aspire to solve other problems, like registering your 35mm or 120 rolls (you find better apps for this in the store). I have also made sure that it is easy to save and reload the data, since part of the motivation was the frustrating experience that apps come and go in the app store. So if you don't want to feel notches in the dark you might want to use this functionality;) I appreciate everybody using it and giving feedback below. I programmed this purely for my needs and for my education but believe that I am not the only one in need of such an application. The app is largely self-explanatory to those who have ever shot large format. It was tested extensively on my iPhone 12pro Max under iOS 15 but should work on older or newer models as well. Maybe the UI suffers a bit on smaller screens.

Silverlog Flash calculates flash exposure using guide numbers — the fundamental relationship between flash power, distance and aperture. HOW IT WORKS Choose what to solve for and enter the other two values. Find the aperture for a given flash-to-subject distance, the maximum distance for a given aperture, or the guide number from a known distance and aperture. Adjust ISO to see how sensitivity affects your working range. FEATURES • Guide number to aperture calculation • Guide number to maximum distance calculation • Guide number from distance and aperture • ISO adjustment • Metric and imperial distance units • Works offline — no internet connection needed • Clean, focused interface • Dark mode support USEFUL FOR • Manual flash photography without TTL • Working out flash-to-subject distance for off-camera flash • Understanding your flash's effective range at different apertures • Film photographers using manual flash units Part of the Silverlog photography toolkit. No account required. No data collected.