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Comment by galago | Hacker News Reader

A lot of cameras are sticking at 24MP because that's where a lot of lenses start to reach a weak point. Also, file size to utility becomes a consideration because most people expect cloud/sharing. I feel like 100+MP is going to be an enthusiast thing for a long time. It seems a lot like car speeds. Every car sold today can go over 100 miles per hour. Some people still care about how fast their car can go, but most don't really think about it or even know their car's top speed.

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I have a couple of photography colleagues who use the 50MP Canon 5Ds. The detail they gather is astounding, more than my 21.1MP can grab even with a teleconvertor on the lens. So they can shoot with shorter focal lengths, which means less weight and better stabilisation.

They can then go into post-processing and "crop the hell outta it" and still end up with more detail than my image.

It is a cliché but high-density sensors really are a "game changer". They give so much potential to reframe the photo after shooting, selecting the most relevant area of the frame and still having enough detail to blow-up to prints.

Exactly this. Being able to crop is why I use a 42MP camera.

Top of the line tools really make a difference in photography. Back in 2007 when taking a photography class, you could see the difference in quality between a top of the line DSLR that some senior students had and point-and-shoot cameras without interchangeable lenses.

Even though the composition was good from both, the difference in quality really made you biased towards photos produced by the higher end gear. Depth of field, sharpness, noise, all those things.

And everything you mentioned as well - not having to take multiple shots, because you can always crop later, not having to get as close to the subject for people photography, so perhaps getting more shots.

A good quality 2x teleconverter will make your sensor the equivalent of 80mp in this context.

Ie with the same lens, a 20mp camera with 2x teleconverter will resolve more detail than a 50mp sensor.

But it's a losing race; adding a 2x teleconvertor halves the amount of light received, so I have to drop my shutter speed and / or raise the ISO to compensate. Both of which are disruptive to image detail.

Plus the distorting effect of the extra glass in the lightpath.

-Unless I am much mistaken, a 2x teleconverter will cost you two stops - meaning 1/4 of the light. (I’ve mostly used a rangefinder in later years; they do not lend themselves well to teleconverters. :-)

You lose almost no light.

You are changing the area of the sensor the part of the scene is spread over.

Its a triviality as a result of us expressing the F number as the ratio of the focal length and the aperture size.

The effective SNR of the sensor is increased due to more sensor being used for a given part of the scene, so the lower light level does not increase noise comparatively.

Yeah. Teleconverters are true lens "stress" testers.

People often forget that 2x increase in one dimension equates to a 4x increase in area and number of pixels. I didn't expect that of this community though, which is how I'm interpreting the down voting here.

This is my profession so if the down voters know something I don't I'm very interested to hear where I've gone wrong.

> So they can shoot with shorter focal lengths, which means less weight and better stabilisation.

It doesn’t mean better stabilization once they crop. The weight isn’t a major factor in stabilization. The effective magnification is.

I think Dingaling means that, if you're holding the camera in your hand, you'll be able to hold it steadier if it weighs less.

Probably, but it's not really true. It's more comfortable to hold a lighter lens but the heavier lens has more inertia so resists micro-tremors more effectively. In the end it's pretty much a wash.

Locked down on a good tripod with a remote shutter release, the very best prime 35mm lenses will resolve about 40Mpix worth of useful detail at their optimum aperture. The pro-level PJ zooms (24-70mm and 70-200mm f/2.8) will manage about 30Mpix on a good day. Handheld, all bets are off - you're at the mercy of image stabilisation and your own hands. In many circumstances, you'll have no choice but to use a sub-optimal ISO or aperture setting to get the shot, losing even more effective resolution.

High resolution sensors are very useful in some applications, but you'll often see little or no benefit in real-world use. All the major manufacturers offer both a >40Mpix and a ~24Mpix sensor option in their high-end cameras, because resolution isn't the be-all and end-all of a sensor.

The Canon Mark II 'big white' primes are said to be designed for 100MP. The smaller Mark II / III zooms are indeed in the 40 - 50 range. Bear in mind that the 24MP crop sensors have been pushing past the 50MP-full-frame-equivalent for several years and really show up any lens flaw.

The one example that stands out is the Canon 70-200 f4 IS zoom, which has an ageing early-digital-era reputation for being razor-sharp but never managed that even on my old 1Ds III and looks like mush on a 5Ds. Hence a Mark II is to be released this year.

Interestingly the even older non-IS f4 version was on the list of lenses approved for the 5Ds, which shows how difficult adding those extra optics makes lens design:

https://www.the-digital-picture.com/News/News-Post.aspx?News...

I have a 5Ds. Once you have used one, you know that medium format is dead in the water as a category. That said, for most shooting scenarios they are definitely complete overkill, and lens quality becomes paramount.

I tend to think this 120MP sensor is probably going to be sold commercially as a surveillance product first.

There's a lot of need for products like this in stadiums, arenas, large public areas etc.

That marketing video seemed to be highlighting specifically that. They even had the shot of the security woman at the very end.

See also WAAS [11] and ARGUS [22]

[11] https://foxtrotalpha.jalopnik.com/how-one-new-drone-tech-fin...

[22] https://www.youtube.com/watch?v=0p4BQ1XzwDg

The file size is insane though - imagine having to store hours of video from hundreds of 120MP cameras. Even the bandwidth required to continuously stream hundreds of those cameras to a central location would be enormous.

If it's for surveillance, you connect them to gigabit fiber.

Sony had an ad for a eye-of-sauron type application for a gigapixel imager array that could track someone across an entire city from one location. Surveillance will be the major consumer of >100MP sensors.

> I feel like 100+MP is going to be an enthusiast thing for a long time.

Or maybe not? Optical system design often allows you to trade one thing for another. So for instance, years ago, light field capture (each "pixel" is a little lens in front of several real pixels) was bottlenecked on image size. You're spending resolution to buy angle information. An order-of-magnitude or two of resolution. There's also exposure (HDR), and time (anti-blur), and so on. 100 MP sounds like a lot... until you start spending it in order-of-magnitude chunks to obtain other system features.

The lens quality barrier at 24MP isn't arbitrary; that's basically the equivalent digital resolution you get from 35mm film.

Not true - obviously it slightly depends on the grain of the film but the theoretical resolution of high quality 35mm film is ~87MP

Full frame, obviously.

Much higher brightness range on film too (potentially -- depends on the film of course).

You'd need to be using Kodak Technical Pan at a rated speed of 12 to 16 (before filter factors, for continuous-tone images with smooth gradients) in order to get there, though. Kodachrome 25 (in the K14 process version) and Ektar 25 weren't terribly far behind, but neither had a great deal of latitude. And you'd also need something a little flatter than the typical film aperture and pressure plate to really use it. More typical 35mm films - those with usable sensitivities for general photography - wouldn't get you anywhere near there.

Sure, there’s tons of variation of course and 87 is the upper limit, but from what I’ve read it’s still the 40-50MP range before you hit the limits of a decent typical 35mm film.

Lens quality does start to become a factor a bit earlier than that too.

A lot of the comparisons I've read (and internally Leica's own tests) say otherwise.

https://petapixel.com/2014/12/18/comparing-image-quality-fil...

I mean... in that very article the 80MP camera looks worse than film (tho more sharpened, go go digital image processing!)

You appear to have provided counter evidence to your own position.

Take a look at the 35mm section, that's explicitly not the conclusion of the article.

"The results are very impressive and from our comparisons we think scanned color slide film has a digital equivalent resolution of between 12MP and 24MP depending on what aspect you look at (12MP for overall sharpness appearance, 14-16MP for luminosity resolution, and 24MP for color resolution). These figures are estimates based on a good Imacon or Drum scan and would be even higher for projected or enlarged images."

So you're basically reading that and going, well I think I'm right anyway.

There are all kinds of films out there, including very very high resolution ones. Gigabitfilm is supposedly 720 lp/mm, which would give you

    36*24*(720*2)^2 = 1.79 gigapixels

(theoretically, of course)

To Canon's credit starting with the 35mm f1.4L II a few years ago, they've started releasing pro grade lenses with the optical performance to handle extreme resolution sensors.

Still though 24MP is more than enough for me.

The lens 'weak point' depends on the aperture you're using. Even relatively inexpensive lenses will resolve a hell of a lot of detail at f/8.

I do agree that it's an enthusiast thing, and will remain so for a long time, but it's not that hard to utilize that resolution.

I think most lenses, cheap or not, already lose resolution at f/8 due to diffraction.

Most of my lenses have resolving peaks somewhere between f/4 and f/5.6.

We need a better file format that JPG for sharing these large images.

JPEG is a compressed format; it intentionally sacrifices quality for smaller size. It still has its uses, but it should never be used where image quality is the primary concern. There are many widely-adopted alternatives that suit other purposes and have no data loss. One alternative, PNG, is supported everywhere that matters, but there are plenty of others.

We need lossy state of the art codecs, PNG sucks for large images. TIFF and EXR are also great. But I think we need a lossy large image format, probably based on AV1 and similar technology.

We have jpeg2000 and dng.

JPEG is still used because of ubiquity and because it always was good enough, we have over two decades of better replacements lined up if we need them.

> I feel like 100+MP is going to be an enthusiast thing for a long time. It seems a lot like car speeds.

Is there anything in photography analogous to speed limit? Because that's often a reason why folks don't go over say 80mph not to mention well over 100.

If tomorrow 100MP cameras appeared and were cheap enough I don't think people would think twice about getting them.

Yes, people would buy them, but they do require very disciplined shooting. That kind of resolution is very unforgiving of even slight movement or mis-focus.

> Is there anything in photography analogous to speed limit?

Maybe price, weight and the size of the RAW files they generate? At some point it's not worth to invest more.

That's true if you're using 35MM equivalent lenses. One must switch to medium format sizes.

Unless you're looking at the Mamiya or Hasselblad MF lenses, good 35mm lenses tend to out-resolve MF and definitely LF. Projection circle is only part of the effective resolution.

Only really cheap zoom lenses would max out at 24MP. Most lenses will have no problem with 100MP.

I'd say even 24MP is an enthusiast resolution. Most people are now fine with their smartphones, and the most they do is share their photos on social media sites in very low resolution.

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