With Smartphone Photography, Size Matters ⭐

I’ve been researching smartphone photography and video capabilities and I keep running into the same issues. While Apple, Google, Samsung, and other smartphone makers are keen to promote these capabilities in their devices, it’s curious to me how much information is misrepresented or simply ignored. And some of it is, I think, crucial.

Granted, some of this is these companies simplifying descriptions of complex topics that many people wouldn’t understand otherwise. But it can feel deceptive, too.

For example, when Apple claims that its iPhone 17 Pro models deliver “8x optical zoom,” it’s crossing a line of sorts because these phones are only capable of 4x optical zoom when using the full telephoto lens sensor: The 8x zoom is a 12.5 MP crop of what is typically a 25 MP original image. Likewise, the “200 mm” telephoto lens is not literally a 200 mm lens, it is a tiny lens that delivers a view that is roughly similar to a real 200 mm lens, or what we call a 200 mm equivalent. I owned such a lens for my Minolta SLR camera in the late 1980s and 1990s, and they are physically large (6 inches-ish in length) and heavy, and they have a fixed focal length, so they can’t zoom at all either.

Computational photography can help improve matters dramatically and close the gap between digital SLRs and smartphone cameras. But it should be obvious to anyone that a tiny smartphone camera lens, something that’s typically smaller in diameter than the contact lenses I wear in my eyes every day, will never deliver the same quality as a large physical camera lens. Less obvious, perhaps, is that each of the lenses in the camera system of your phone is a different physical size and provides a different level of quality. That is, even though all three of the rear lenses on the iPhone 17 Pro models are high resolution 48 megapixel (MP) sensors, the main lens is always the biggest and highest quality lens, no matter the phone.

And there is so much tied up in that fact that it’s difficult to even know where to start.

But start we must. Many are familiar with the notion that megapixels aren’t all created equally and that a higher megapixel count doesn’t equate to higher quality images. But what that really means is that a small 48 MP sensor will typically deliver inferior photos than a large 48 MP sensor, all other characteristics being equal. In other words, megapixels do matter, but sensor size really matters.

I celebrated when Google and then Apple finally upsized all their rear camera lenses to high megapixel counts (at least in their respective Pro models). But what smartphone vendors don’t do is advertise the size of those sensors. In fact, I can’t find this information anywhere. All we get are vague and occasional comparisons. Not to harp on Apple, they all do it, but it claims that the iPhone 17 Pros feature the “longest ever” telephoto lens (equivalent) and that its sensor is 56 percent larger than that of its predecessor. That’s a big improvement, but we don’t know the size of the previous sensor, just as we don’t know the size of the current one.

You can see this for yourself if you look at the rear camera system on your phone at the right angle and with the right lighting. But the image at the top of this article, which is from Apple, illustrates the differences nicely. In addition to being different shapes, which is interesting, the lens on the far right (in the image) isn’t just bigger than the other two, it’s much bigger. And that, of course, is the main (wide) lens.

In some ways, the chicken and the egg on this is important, meaning it’s not clear if the main lens is always the highest quality lens because that’s the one people use the most and so phone makers focus (ahem) more on it than the others (or vice versa). But it’s a fact, and with all lens sensors getting bigger over time and offering higher megapixel counts (resolution), we’re seeing more instances in which a sensor crop is more desirable than zooming, despite the reduced resolution when doing so. Google and Apple both do this, and both are doing it more. (As with the 4x/8x zoom on the latest iPhone Pros.)

And that is why having a single camera lens on the rear of a phone, as is the case with the iPhone 16e and iPhone Air, may not be all that bad for many users. I’m not a fan of Apple marketing the single rear camera lens on the iPhone Air as “two advanced cameras in one,” but it’s fair to say that the experience for the mainstream users who purchase this device is like having two lenses. If you change the default resolution, you could even get the same 12.5 MP images regardless of how or whether you zoom. That may be good enough for most.

I have a bigger problem with Apple marketing the iPhone 17 Pros as having a rear camera system that is “like having 8 pro lenses in your pocket,” given the audience. But at least they say “like.” And those customers are likely more savvy about what it is they’re really getting. At least some of them.

It’s not clear to me why phone makers don’t clearly state the size of each camera sensor. (And if anyone knows where I can find this information, I am quite interested to hear about it.) But I suspect that will change now that most pro camera systems have consistently big megapixel counts and as the sensor sizes keep growing. It can and should be a marketing comparison, and unlike with megapixels, it’s one that universally matters.

Or maybe the pixel counts keep growing and we start cropping 96 or 128 MP images down to 48 MP or whatever to achieve a better resolution for cropped images. Whatever happens, some clarity here would be welcome, as would some kind of an in-camera heads-up that whatever crop or zoom we’re doing—8x zoom on the iPhone 17 Pros, for example—will result in a lower resolution final image. That actually matters to some of us. Including those who spend extra on that pro model phone.