Vintage Lenses on APS-C and Micro Four Thirds: Crop Factor, Flange Distance and Speed Booster Tables
Put a Helios 44-2 on a Fuji body and it stops being a 58mm lens, at least as far as framing goes. It frames like an 87mm. On an Olympus Micro Four Thirds body it frames like a 116mm. Same glass, same aperture ring, very different lens in practice. Most of the …