If I shot with HD cameras at a native 1.78:1 ratio (1920x1080), how should I crop to…
1.85:1?
2.39:1?
On blu-rays I find different values and I don't know why. For example, with 1.85:1 I see black bars on the top and bottom with 22 pixels each (1920x1036) and with 20 pixels each (1920x1040). But on UHD blu-rays I always see the same thing, bars on the top and bottom with 42 pixels each (3840x2076).
In the case of 2.39:1 something curious happens. Most blu-rays are 2.40:1 instead of 2.39:1, that is, black bars on the top and bottom with 140 pixels each (1920x800). I find 2.39:1 (1920x804), and black bars on the top and bottom with 138 pixels each, on rare occasions.
What is the correct pixel value? 22, 20? 140, 138?