Almost every movie poster I’ve seen from 1950something to the early 70’s has had “in CINEMASCOPE” blaring on it. Exactly what is Cinemascope, and why was it abandoned?
Here you go. There have been numerous threads on various widescreen processes over the years, if you want to get some practice with the SDMB Search function. 
Darn. I went looking for that real cool link I found months back on wide screen formats and ArchiveGuy already put it up.
Basically, Cinemascope refers to a process in which anamorphic lenses are used to squish the picture in the horizontal dimension so that the entire area of the film frame can be used. When the film is shown, a special lens is used to spread out the image so that it fills the width of the screen. If you look at the film for a “scope” movie up close, all of the people look really tall and thin.
In traditional “flat” films, the aspect ratio of the movie screen makes it such that there are substantial swaths of real estate on the frame that are not used, so these other techniques came about in an attempt to utilize more area of the film, increasing resolution.
Anamorphic lenses have not been abandoned. When I was showing films ten years ago, over half of our films were shown with a “scope” lens. I suspect that they don’t shout much about it in the same way that you don’t see too many motels these days sporting the words “C o l o r T V” on a huge sign in multi colored letters since it is a given.
It is not uncommon to show “flat” trailers before a “scope” film and modern projectors have a turret lens affair that rotates when a special signal is given (usually a bit of foil cue tape on the film).
Damn straight anamorphic lenses haven’t been abandoned! I shot my short film in anamorphic, which I thought was unusual for a short film, but there were generally one or two others as well at the fests.
(Sorry. Nothing really to add that ArchiveGuy’s link doesn’t cover. But I figured since this thread was going to come up in one of my vanity searches anyway, I might as well post to it. :D)
Wrong, and wrong. The total frame area on a CinemaScope film is virtually the same height and width as a “flat” movie.
And an anamorophic image decreases, not increases, resolution, at least horizontally. It forces the same frame size to be projected onto a wider screen than normal.
That bad, huh?
Perhaps I didn’t express myself well.
After the gate in the projector masks off unwanted portions of the frame to show “flat” film, there is less usable grain making its way onto the screen. As you stated, the total area is the same, four sprocket holes in either method, but in “flat”, a good portion of that frame is masked off.
I wasn’t really considering the exact directions in which resolution increases, but it would appear that “scope” resolution increases vertically by a good amount and decreases horizontally by a somewhat lesser amount.
I base my statements about resolution and area (in a general sense) on the idea that on “scope” film, every last bit of the frame is used and displayed, while in “flat” film, it is quite common and acceptable to have thick black frame lines between the frames, throwing away perfectly good grain.
Specifically, CinemaScope changed the aperature size from 0.825" x 0.600" to 0.912" x 0.715". That is, the aperature height was increased by 10.5%, and the aperature width was increased by 19.2%
Meanwhile, CinemaScope lenses increased the screen ratio from 1:1.37 to 1:2.55 (later 1:2.35). That is, the screen width was increased by 86%. Given that the aperature width only increased by 19.2%, this represents a significant net loss in horizontal resolution.
Thanks for the stats, Walloon. Remind me never to say “higher resolution” again when I really want to say “more dots on the screen”