Normal aspect ratios/resolutions used in cinemas:
2K DCI F Flat 1.85 1998 x 1080
2K DCI S Scope 2.39 2048 x 858
4K DCI F Flat 1.85 3996 x 2160
4K DCI S Scope 2.39 4096 x 1716
All cinemas have presets for F and S.
Not commonly used aspect ratios/resolutions
DCI 2K C Full Container 2048 x 1080
DCI 4K C Full Container 4096 x 2160
Full container is not commonly used in cinemas. If a DCP is made in Full Container C, it will often be played in Flat with some cropping on the sides.
Letterboxed and pillarboxed aspect ratios inside Flat and Scope
Films made in 2:1 or 2.2:1 aspect ratos are mastered in letterboxed Flat instead of Full Container or Scope. When the film is mastered in Flat, the side masking setting for Flat still fits the sides. The DCP is marked with the custom aspect ratio, like this F-220 for 2.2:1.
Films made in 2.66:1 are mastered in letterboxed Scope.
It is possible to make new projector channels/presets for F-220 2.2:1 and similar aspect ratios to avoid letterboxing in a common height cinema. In a common width cinema, every format wider than Flat is letterboxed. In a common height cinema, every format wider than 2.39 Scope is letterboxed.
A new channel based on the flat channel for 2.2:1 in a common height cinema would:
-Add more power to the lamp
-Be more zoomed in
-Have a new focus setting
-Have new digital masking. And ideally a new physical side masking setting.
A DCP made with letterboxing should have subtitles above the letterboxing so it is possible to make a custom projector setting.
F-220 2.2:1 (Tenet), F-178 1.78:1 (HD), and F-210 2:1 have been used on some films and some cinemas have made presets for them.