David Mullen ASC
Moderator
I watch netflix on a 4k screen, I notice a lot of indie films that have huge grain and I stop watching them(actually stopped watching a "ok" indie film yesterday since it was just to irritating on the grain, on a OK film that isn't messed up I will at least keep it on).
What I think is happening is the 2k film scan on Indie's is multiplying the grain size, I don't see this on 4k film scans which are more common on the non-indie's. I think it has to do with how the sample was done, and if the grain happened to be in the middle of the sample | between two pixels | between 4 pixels - it takes that one grain and hugely multiplies it for between 1 and 4 pixels.
No a 2K does make grain larger than a 4K scan -- if anything, 4K scans are considered to be more grainy than a 2K scan. I think what you are seeing is the effect of post-sharpening, which is more common with 2K. It will make the grain stand out more.
But I think the bigger issue is whether visible grain is a bad thing or not. If the grain is there in the original, I'd rather see it preserved. The only reasons to employ grain reduction would be in restoration work to save a dupe optical effect that has aged faster than the surrounding shots, or in a modern D.I. session where the cinematographer needs to fix a shot or scene that doesn't intercut well due to excessive graininess.
But otherwise I can't imagine stopping watching a movie because of visible grain... The thing with 4K distribution is that you're going to notice more clearly the differences in sharpness and grain -- is that a bad thing? Isn't that one of the advantages of 4K, that differences stand out?