Mike Fox

S16 v 16. The new GBCT Kelly 16mm version was designed for Super16. As the original 16mm aperture area is less than that of S16, the Depth-of-Field (for 16mm) will be increased. But remember, ALL Kelly Calculators were designed for accuracy on the BIG SCREEN (ie, cinema) where DoF becomes critical and cannot be judged just by checking it by eye-focusing or what it looks like even on the best of monitors. Perceived DoF is a factor of the degree of magnification. What looks sharp on a frame width of, say, 32in (or much less) is very different when seen on a 40ft screen. You can only see your actual DoF when viewing the material on a cinema screen (film or digital). It was why the Kelly was invented back in the Fifties. The modern Kellys still work superbly well and to a finer degree of Circles of Confusion than they did back in the Fifties. Most importantly, you can rely on them 100%.