jtulli said:
Thats surprising I would assume a 70mm blow up would be much closer to the negatives in detail. Wouldn’t it technically still be best to scan at 6 or 8k because when viewing on an 8k tv you would see more of the natural grain rather then the 4k pixel structure. even though there may be little to no more perceptible detail.
“Closer” is a relative term. Optical duplication reduces fine detail and adds another layer of grain. The more times you do this, the worse it gets. 70mm gets very slightly less loss of fine detail, and the added 70mm grain is finer and less noticeable than the chunky grain of a 35mm print, and it’s usually duplicated from a source closer to the OCN – so yes, a 70mm print is a nice resource, when you’re stuck with prints.
But you’ve still got baseline quality issues to contend with. I say that a pristine high-quality negative could be worth scanning at up to 6K. But Star Wars negatives are not that (it’s possible that the negatives may not be worth scanning at >4K), and even a single pass through optical duplication puts a serious limit on quality.
For example, that six-way Han image up in my first post – that 4K83-based image (bottom center and bottom right) was taken from an extremely high-quality 35mm print source that is duplicated from the same high-level sources as a 70mm blow-up. It’s also using better 1980’s filmstock that adds a less obvious layer of grain to the duplicated image. As far as 35mm prints go, this thing is a unicorn. The best possible source – it’s a wonder that we have it, and I’m delighted with it.
But if you look closely, you’ll see two things about it – one, that in terms of fine image detail, the only image it’s clearly better than is the DVD downscale. The other is that it does resolve the grain better. But there are some caveats about that grain observation – that the grain on the UHD-sourced images is fake anyway, so it’s impossible to do an apples-to-apples comparison on grain alone, and that while it’s a common refrain among film enthusiasts that “the grain IS the image”, that statement is less true the more you move away from the negative. By the time you’re dealing with a projection print, most of the grain is simply grain that’s been added to the image, and was never on the negative to begin with – this type of grain doesn’t create the image, it erases it – the grain added via optical duplication is just an analog form of fake grain – it’s arbitrary destructive noise layered on top of the real image (the real image has its own grain). Honestly one last thing you should notice is the toll taken by degraining the UHD source. This process did clearly wipe away a ton of fine detail on the UHD, but not enough to be equivalent to what’s lost with optical duplication.
What the six-way Han image tells me is:
- DNR is terrible
- DVD is terrible
- A 1440p-ish scan of the print would capture all of the fine image detail on this best-possible 35mm print, aside from maybe the grain, and the extra resolution of the 4K scan definitely takes care of that
You’re not going to see the 4K pixel structure upscaled to 8K. Even on a screen large enough to see the 4K pixel structure, no display’s upscaling process uses pixel-doubling, so it wouldn’t be visible at 8K (and even if it did, you could just upscale it better yourself and then display it at native 8K). At greater than 4K, any grain detail you’re theoretically capturing is purely grain detail, without any associated fine image detail. Yes, technically you could scan a print with an electron micrograph and see the molecular structure of the film. You would get more detail – there’s always more to see at higher resolutions. But none of that detail comprises the image captured on the film. That, I’d say, for prints of these films, tops out somewhere in the neighborhood of 1440p. 4K already provides a generous buffer on top of that.