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Comment by snowwrestler | Hacker News Reader

> A modern full-frame DSLR sensor has greater resolving power than normal medium-format film.

This really depends on the film and MF lens. I've shot 6x6 Provia on a Mamiya 6 and had it scanned at 40MP and 80MP final output sizes; the latter was clearly better. Resolution can be even higher with modern fine-grained black and white film.

> You still want to shoot handheld, so you want a really fast lens to minimise the impact of camera shake.

Or image stabilization, which also adds weight and size.

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>This really depends on the film and MF lens. I've shot 6x6 Provia on a Mamiya 6 and had it scanned at 40MP and 80MP final output sizes; the latter was clearly better. Resolution can be even higher with modern fine-grained black and white film.

Film scanning is a bit deceptive, because film doesn't have pixels. You'll get more resolution from an 80MPix film scan, but that doesn't mean that the film actually has 80Mpix of useful resolution. A lot of information is lost in the conversion between silver particles and a scanner sensor, so you really need to substantially oversample. In the ideal case for color MF film (a ~200MPix drum scan of 6x7 Velvia 50) you might just about match the resolving power of a A7R III, at the cost of a substantial amount of dynamic range - film has a lot of exposure latitude, but it has substantial innate dynamic range compression.

Technical monochrome films can significantly exceed the resolving power of modern 35mm sensors, but at the cost of ~6 stops of sensitivity. Unless you're shooting landscapes or test charts from a very substantial tripod, you won't benefit from the extra spatial resolution. There's still a place for medium- and large-format film, but the inconvenience outweighs the benefits in the overwhelming majority of cases.

Here's a great article that goes in-depth on comparing the resolution and image quality of MF and LF film vs. images from a D800e. A D850 or A7R III has about 10% more linear resolution than a D800e.

https://www.onlandscape.co.uk/2014/12/36-megapixels-vs-6x7-v...

I love this article because it not only looks at lines per mm, it considers other image quality factors like local contrast and color resolution.

The article shows that the Velvia 50 isn't resolving significantly more detail than the D800e's sensor. It's not surprising that the CMS 20 shows more detail. CMS 20 is a technical film that's not usually practical for normal photography.

I'd suggest taking a closer look at the first set of test chart comparison shots. The D800e is not resolving any lines on the chart at all--the "lines" you see in the D800e shot are moire.

You can see the same thing in the comparison shots of the camera. In the D800e shot, the Nikon logo and fine print on the lens are smeared, with yellow and blue artifacts. In the Mamiya Velvia shot, the Nikon logo is sharply defined, with no color artifacts. However, there is grain in Velvia shot.

This is a good example of how there is more to resolution and image quality than just counting megapixels. If you hate grain, the D800e shot is better, despite the moire. If you'll tolerate grain for more resolution, the Mamiya Velvia shot is better.

I've seen the comparison shots - that's what I'm basing my comment on. The medium format film shots don't resolve the lines either - except the CMS 20, which is not a practical film for normal photography. These black and white line pair charts make film look more impressive than it really is, since film has a long "very fine detail at very low contrast" tail. A more instructive comparison would be medium contrast line pairs.

As I said in my other comment, the easy way to prove that a medium format negative can resolve 80MP worth of detail is to provide an 80MP scan which loses detail when downsampled to, say, 40MP. I've asked a bunch of people for examples of such a scan over the years and never received one.

For some reason, the comparison site you link to doesn't provide any of the original files, so it's difficult to draw any conclusions.

>I've shot 6x6 Provia on a Mamiya 6 and had it scanned at 40MP and 80MP final output sizes; the latter was clearly better.

The real test is whether you can find any details visible in the 80MP scan that are lost if it's downsampled to 40MP.

The 80MP scan passed that test for me.

I don't think you understand. The wrong comparison is between the 40MP scan and the 80MP scan. The right comparison is between the 80MP scan and the 80MP scan downsampled to 40MP.

I do understand.

Can you give an example of an 80MP scan that loses detail when downsampled to 40MP?

>Or image stabilization, which also adds weight and size.

In-body stabilization is a great solution for this. f/1.4 primes and in-body stabilization are a great combination for available light photography.

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