A modern full-frame DSLR sensor has greater resolving power than normal medium-format film. You need a really, really good lens to get the full performance out of a >40MPix sensor. You still want to shoot handheld, so you want a really fast lens to minimise the impact of camera shake. Sharp/fast/light - pick any two. Zeiss, Sigma and Sony have broken the old Canon/Nikon duopoly with a range of phenomenally good but relatively heavy lenses that can exploit the full capabilities of modern sensors.
Casual customers who need a "good enough" camera are perfectly satisfied with their smartphone or a cheap kit lens. Aftermarket lenses are inevitably going to target the pixel-peeping crowd who care about every lp/mm, because they spend the big bucks on lenses. There's still a market for lightweight aftermarket lenses, but it's nowhere near as big or profitable as the market for monster glass.
> 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.
>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.
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 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.
> A modern full-frame DSLR sensor has greater resolving power than normal medium-format film.
Scanned at 5,300dpi (which seems to be the higher end offered by negative scanning services), my medium format 6cm square negative yields a 156 megapixel image. [1]
I'm not aware of any crop sensors offering comparable resolution, in fact this round-up of current cameras seems to suggest <50mpx is more likely and I'm sure some of those are "full frame".
Scanning at 5300 dpi or 156 megapixels doesn't mean you have that much resolving power (I can scan a negative taken with a cheap lens at any resolution I want but that doesn't mean I magically get massive resolving power out of my crappy camera and lens).
When scanning traditional film you generally want to scan at significantly above the resolving power to capture all the grain structure and other analog characteristics of the film medium.
The easiest way to measure your resolving power is to print a black and white pinwheel - a large number of alternating black and white pie slices around a circle (more pie wedges is better). Pull your camera back and take a photo. Zoom into the pixels of the photo looking for the point near the center where the black and white regions stop being black and white and turn into a gray. Measure the diameter of the gray circle and use the diameter to compute the circumference (measure in pixels, then use the info about your sensor or scanner to convert from pixels to mm). Count the number of black pie slices and divide by the circumference to get your resolution. For extra fun try opening up one of your lenses to its maximum aperture and then compare the results to the same lens stopped down to f/16 or something like that - it's much easier to make a lens that performs well at a small apertures than large ones, and zoom lenses are harder to design well than fixed focal length prime lenses.
To get really trippy, just look at the pinwheel with your eye, and you can use the same technique to measure the angular resolving power of your eye (using your distance from the chart to measure the diameter in angular degrees rather than in mm).
Depends on the scanner! The "listed" DPI targets for scanners often aren't realized in practice. Take a look at the "image quality" section of this plustek optifilm review [0]: this one is actually very good. It's common for the "best" quality to come from scanning at 6,000+ DPI and downscaling to get ~3,000 effective DPI.
In practice, it's a _lot_ of work to get more than 3,200 DPI out of a 120 negative. You can certainly do it if you wet mount and use a flextight X5 scanner [1] (list price $23,000).
There's also the question of how fine the grains are in the film emulsion you're using. If you use ISO 50 film, you're likely to get more than 3,200 DPI of detail in the negative, but you don't have unlimited detail! Faster films have bigger grains - that's why they're faster!
So just keep in mind that the amount of detail you can extract is a combination of the following: how much detail the lens transmits, how much detail the photographic medium records and how much detail the digitization process retains. Digital cameras are a handy hack in that the photographic medium and digitization process are one step! Film is more complex.
The easiest way is to print optically rather than digitally. A midrange enlarger lens is easily capable of outperforming a high-end scanner, and high-end apo enlarger lenses are still top dog. Avoiding the quantization inherent to pixel-based formats makes it much easier to deliver resolution to paper.
I agree that there are good aesthetic reasons to avoid digitization all together (or even just digitize prints). Color correction with scanned negatives can be a true nightmare if you want to preserve the look you would get with a traditional print.
Personally, I've always shared pictures primarily through the internet and so traditional printmaking has been less attractive.
Really, you just have to accept that a print made from a negative is a picture-of-a-picture. There is no inherently "right" way to convert a negative to a positive, any more than there is an inherently "right" color balance for a film to make the first capture with. The color balance and contrast levels you select are just an interpretation of the image, just like the initial exposure.
It's not too bad to get color balance right when scanning, as long as you didn't mess up the exposure too badly. Set the white and black points according to the histogram, adjust the gray point until the contrast looks right. Then, if there's color shifts in the highlights or shadows, play with the white/black points on one of the color channels until it looks right. Then pull it into Lightroom and do your final adjustments. It's intimidating at first but mechanically it's not that difficult, after you do a couple rolls you'll have the hang of it.
(background: film is basically three separate emulsions with their own color response curves, that happen to look normal when shot at box ISO. The farther you get away from box ISO, the more color shift you tend to get, eg clouds will start going yellow in an overexposed image)
Also worth noting that a flat scan is preferred to a high-contrast scan in most cases... you can always increase contrast in Lightroom but you can't pull back data that's clipped to zero or doesn't have sufficient bit-depth for good tonality. To phrase it more specifically, you want to try and allocate a good chunk of your bit depth to whatever tonal ranges are significant for a particular image, while trying not to clip anything to pure black or pure white.
Also, you should definitely give wet printing a try, it's a lot of fun for techie types who don't work with their hands for a living. You do pretty much have to be shooting B+W these days, not a whole lot of people still wet-printing color anymore, but as with everything B+W it's quite simple. With variable-contrast paper, you just make a couple exposures on test strips to find your highlight exposure and shadow exposure, then add these to produce a final print (split-filter printing/split-grade printing). You can then scan the finished print, if you like.
It's more of a fun thing than a technical necessity for 8x10 prints of 120 film, there is plenty of detail there for a 8x10 even on a basic flatbed scanner. But if you are doing 8x10s from 35mm film or larger prints from 120, then it's usually noticeably superior to do wet prints. If you are really going balls-to-the-wall on your hybrid digital workflow you can get a decent 8x10 or maybe 11x14 from a 35mm negative, but you'll need something like a Flextight or a drum scanner, which start getting pretty expensive to buy and run. Or, you send it out to a pro shop and pay $100 to have them scan it for you.
I could scan a blank piece of card at 156 megapixels, but that card wouldn't contain 156 megapixels worth of information. You're scanning discrete particles of silver metal, which are effectively opaque and have a finite size. Shoot a test chart and you'll see what film is actually capable of resolving.
Basically, to make a film 'faster' you capture phonons from a larger area. Or the other way around, film that can resolve very fine details needs a lot of light.
Film has a built-in low pass filter. Typically 'sampling' in film is random enough that you can capture very fine detail if the contrast is high enough. It behaves quite differently from digital sampling techiques.
For this reason, you want to scan film at a very high resolution. But that doesn't mean that the image actually contains a huge of informaion.
Casual customers who need a "good enough" camera are perfectly satisfied with their smartphone or a cheap kit lens. Aftermarket lenses are inevitably going to target the pixel-peeping crowd who care about every lp/mm, because they spend the big bucks on lenses. There's still a market for lightweight aftermarket lenses, but it's nowhere near as big or profitable as the market for monster glass.