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Comment by shortcake27 | Hacker News Reader

I ditched all my cameras 5 years ago in favour of convenience. I’m a bit disappointed that the difference is still so large. I was convinced phones were going to approach crop sensor quality but it’s not even close, the 80D completely smoked it.

> There is a notable drawback for the iPhone 15 Pro Max in the 3X to 4.9X range (~72mm to 119mm full frame equivalent), as it’s stuck using the main sensor, rather than switching to the telephoto.

I’m super glad Apple couldn’t figure out the tech to get the 5x lens in the non-Max models. I make way more use of 3x than 5x. Cropping the main sensor up to 5x is a bad call IMHO. This is the equivalent of walking around with a 24mm and 120mm prime. Who’s doing that? MaxTech dropped a vid today and the 4.9x shot is atrocious; the 3-5x range is basically unusable on the 15 Pro Max models.

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I quite often find myself in situations where I'm wishing I had my Sony HX400V. Despite having a recent iPhone that can take stunning shots, it absolutely falls down when trying to take photos of dramatic landscapes or low light (try taking these[1] photos of the moon on an iPhone!).

I may have to just keep a normal camera charged and sitting in my car for when I'm out.

[1] Some random photos I've taken of the moon https://flic.kr/s/aHBqjAVLCE

There's only so much you can do with a tiny sensor and mass produced plastic optics. The design going into the optics is incredible but big glass is coveted for a reason.

You say 'mass produced' and 'plastic' as if these were obviously bad things, but why?

Mass production brings down costs and makes it economical for manufacturers to spend more on R&D. If Apple was selling only as many iPhones as Cannon sells cameras, you'd be paying through the roof for all the advanced technology that goes into the iPhone camera system. I'd also point out that all modern lenses and cameras are mass produced. The lenses are not hand-ground!

Plastic moulded lenses enable aspheric designs that would be impractical or impossible to make out of glass. Given the size constraints imposed on smartphone camera lenses, the lenses would probably perform worse, not better, if they were made out of glass (which would require totally different optical designs).

> I was convinced phones were going to approach crop sensor quality but it’s not even close, the 80D completely smoked it.

What is the size of a crop sensor (either APS-C, or even m5/4), and what is the size of the typical phone camera? How functionality do you have with aperture with a camera lens versus that of a phone (which often isn't real/physical, but may be simulated aperture)?

What’s the size of a photon? You seem to be suggesting that the limiting factor is the physical size of the sensor, which is totally absurd. Photography optics are not even close to approaching the limits of physics.

Wrong. Silicon image sensors are benchmarked by their "quantum efficiency" - the number of electrons generated by a photon. That number is something like 0.5, which isn't far from 1.0. There is very finite room for improvement in sensors. https://en.wikipedia.org/wiki/Quantum_efficiency

Now, the following point is not well-known, but the most important thing that determines image quality is simply the frontmost piece of glass in a camera system. Not the sensor size, not the ISO. The front glass determines how many photons you receive per second, how much the depth of field is, and how noisy the image is.

For example, shoot with a certain lens on a full-frame sensor. Now take that lens, put a "speed booster" behind it, and shoot with a crop sensor. Both images will come out essentially the same in terms of field of view, depth of field, and noise. Again, the front glass is what matters, and everything behind it in the optical system are just technical details.

Also as a reminder, shot noise is proportional to 1/sqrt(n), where is n is the number of photons. There are a very finite number of photos you can collect per pixel per aperture per second in real-world shooting situations, and that number is something like 10000. https://en.wikipedia.org/wiki/Shot_noise

> "quantum efficiency" - the number of electrons generated by a photon. That number is something like 0.5, which isn't far from 1.0.

QE is a ratio as described by your Wikipedia link. There is a massive difference between a ratio of 0.5 and 1.0!

0.5 to 1.0 is just one F-stop in photography. If you make your sensor 2× better, that's not going to overcome a 100× reduction in front glass area when moving from a DSLR to a phone.

No, I’m saying you have completely misunderstood QE. 1 is the upper limit - 100% efficiency. You can’t just say 50% is very close to 100%!

> Photography optics are not even close to approaching the limits of physics.

The relationship between aperture sizes, pixel sizes, and diffraction sizes certainly do effect the quality of images:

* https://www.cambridgeincolour.com/tutorials/diffraction-phot...

* https://fstoppers.com/science/closer-look-lens-diffraction-5...

* https://www.edmundoptics.ca/knowledge-center/application-not...

* https://en.wikipedia.org/wiki/Airy_disk

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