David Mullen ASC
Moderator
True 15-perf 65mm IMAX photography shot on slow film in daylight is amazing to see on the big screen, but there have been a lot of smaller formats used for IMAX release, including 3D HD like for "Ghosts of the Abyss", not to mention all the 35mm and HD movies that have gone through the IMAX DMR process (de-graining and re-sharpening). I'm sure 4K RAW will be used for some IMAX project, no doubt, and it may look OK. At least it won't have to be degrained, and that will help retain some sharpness.
As much as everyone says that 35mm is more like 2K than 4K, every HD movie I see on the big screen (technically 1.9K, nearly 2K) looks slightly soft unless it is digitally projected. Last one I saw was "Speed Racer", before that "21", "The Other Boleyn Girl", and "Forbidden Kingdom", the last looking the best because I saw it digitally projected.
To really be crude and inaccurate (using pixels as a measure of resolution, which I said was not a good idea), I'd say that good 35mm anamorphic photography is more like 4K, good Super-35/1.85 is more like 3K, and HD is naturally like 2K. And your more mediocre work in 35mm is more like 2K.
As for the advantages of grain, the biggest advantage is something that can't be simulated in post, that the capture medium changes the position of its "photosite" (the silver halide grain) on every frame, reducing the chance of any aliasing artifacts. Sensors with fixed patterns of photosites, on the other hand, need anti-aliasing filters to get rid of the problem, thus losing resolution. Adding grain in post just adds a graininess to the image, which is fine if you want that.
Another benefit to some moderate grain on a theater screen is that if the grain looks sharply focused, it gives the impression of a sharper image, which is why some scenes shot on 50 ASA film, nearly grainless, can seem blurrier than scenes shot on grainier stock. Digital has the same "problem", the grainless image forces the eye to look at the true sharpness of detail in the frame and judge that. This is one reason, I believe, that still frame comparisons almost always show that the 35mm movie frame has less detail than some 4K digital frames, yet the impression when the movie is projected is that the digital image seems softer than the film image.
As much as everyone says that 35mm is more like 2K than 4K, every HD movie I see on the big screen (technically 1.9K, nearly 2K) looks slightly soft unless it is digitally projected. Last one I saw was "Speed Racer", before that "21", "The Other Boleyn Girl", and "Forbidden Kingdom", the last looking the best because I saw it digitally projected.
To really be crude and inaccurate (using pixels as a measure of resolution, which I said was not a good idea), I'd say that good 35mm anamorphic photography is more like 4K, good Super-35/1.85 is more like 3K, and HD is naturally like 2K. And your more mediocre work in 35mm is more like 2K.
As for the advantages of grain, the biggest advantage is something that can't be simulated in post, that the capture medium changes the position of its "photosite" (the silver halide grain) on every frame, reducing the chance of any aliasing artifacts. Sensors with fixed patterns of photosites, on the other hand, need anti-aliasing filters to get rid of the problem, thus losing resolution. Adding grain in post just adds a graininess to the image, which is fine if you want that.
Another benefit to some moderate grain on a theater screen is that if the grain looks sharply focused, it gives the impression of a sharper image, which is why some scenes shot on 50 ASA film, nearly grainless, can seem blurrier than scenes shot on grainier stock. Digital has the same "problem", the grainless image forces the eye to look at the true sharpness of detail in the frame and judge that. This is one reason, I believe, that still frame comparisons almost always show that the 35mm movie frame has less detail than some 4K digital frames, yet the impression when the movie is projected is that the digital image seems softer than the film image.
