Sparked by some of the discussion about how to handle IMAX in a CIH world, I've been pondering what an idealized, cost-is-no-object screen would look like. I am coming at this very much from a CIH angle, and I firmly believe that CIH is the correct approach easily 90% of the time. But there are outliers - IMAX, especially in its modern-day, variable AR incarnation, is one. Another is Ultra Panavision titles, which, being wider than 'Scope, wind up being letterboxed on Scope screens. There are only a handful of Ultra Panavision releases, but, on the other hand, there are only a handful of true IMAX titles best delivered at 1.89.
A very small thing to address as well is the fact that Super Panavision titles are not as wide as 'Scope, despite having much higher resolution in the original images - arguably Super Panavision should be displayed with a larger image area than anamorphic 35mm.
Here's what I came up with - building around a CIH paradigm, with a viewing distance of 2.0x screen height, almost all content can be viewed at CIH by adjusting the side masking. 1.78, 1.85, 2.00, 2.39, 2.55, 2.76 - all accommodated comfortably in the CIH area.
Then, on the day you pop in Lawrence of Arabia, you keep the same width as Scope but adjust the height to get you to the 2.20 AR of Super Panavision. And likewise, when you decide to watch some Christopher Nolan you keep that same width but keep opening the top & bottom masking all the way, resulting in an AR of 1.89 and a viewing distance for full frame imagery of around 1.6x.
Because the number of titles that *need* this additional screen area is so small, I think this exercise does show how valuable a CIH approach is - there's a lot of expense involved in accommodating 30 or 40 movies that need to be wider or taller than a ~2.39 screen CIH cinema can handle. But it's also an interesting thought experiment on how to build a screen that follows CIH guidelines while also accommodating some of cinema's most remarkable films, should you be lucky enough to be building a cost-no-object home theatre.