Zone Tool vs LF Companion

With this tool you can calculate your exposure and needed adjustment for development. It uses zone system theory originally invented by Ansel Adams and Fred Archer. First decide zone of your shadows and measure the shadows. Then device highlight zone and measure the highlights. Measure these with the film ISO you are going to use. You also need to decide shutter speed in beforehand. The app calculates exposure aperture for you and also tells if you need to shorten (N+..) or expand (N-..) your development time. You will get best results with a spot light meter but mobile apps will probably do fine.

LF Companion is a simple assistant for photographers of any kind. The core functions are designed to help you become a better image-maker. The 4x5 mode flips your viewfinder to mimic looking through a large format camera. Combine this with your preferred grid size to make the perfect composition every time. Reviewing your 35mm, 120, or sheet film negatives on the light table? Use the Invert Colors toggle to review your film without modifying your iPhone's accessibility settings. Turn on the 'Save Photo with Filters' toggle to create digital contact sheets straight on your device - now your photograph's are ready to head straight to Instagram, Facebook, or wherever for editing and sharing. Be sure to use #lfcompanion when sharing your photos!