As it turns out, there’s little reason to ever zoom in on a smartphone (or most digital cameras, for that matter). You’re sacrificing resolution without gaining much.
There are exceptions, of course, but for most phones, it’s not helping you get a better picture! The software is tricking you into thinking you’re magnifying the image when you’re actually not.
Digital Zoom VS Optical Zoom
Part of the issue is that we use the word “zoom” for two very different processes.
Optical Zoom – This is what you’re really thinking of when you say “zoom in.” It magnifies the image. Like a telescope or binoculars, it allows you to look at things further away with greater clarity.
Digital Zoom – This is a software effect. The camera lens is NOT magnifying anything. The image you see when fully zoomed out is the same as the fully “zoomed in” one. “Zooming” in this instance is just cropping the outer parts of the same image, and increasing pixel size (or extrapolating them).
What does all this mean? Simply put, zooming in on a digital camera isn’t doing you any favors. You could just take the full photo, totally zoomed out, then blow it up and crop to get the same image.
Yeah. Crazy, right?
It makes a lot of sense when you think about how cameras and zoom lenses work.
Defining Camera Zoom
A camera, in essence, is just a lens and a light-catching sensor.
The relative distance of the lens from the sensor is what determines the magnification (or zoom) of an image. Optical zoom, true zoom, is a measurement of focal length. The focal length is the distance from the center of the lens to the sensor.
When you’re using a top-notch camera with a variable zoom lens, the way it varies the zoom is by moving the lens away from the camera. The effect is that a smaller amount of light, a smaller area of focus, takes up the same amount of space on the sensor – effectively magnifying it.
That’s the concept and mechanics behind optical zoom. It makes sense now that a smartphone with a single, immovable lens is incapable of true optical zoom.
How to Achieve Optical Zoom on a Smartphone
That’s not to say that optical zoom isn’t possible with smartphones. On the contrary, it’s pretty easy to acquire once you know that you don’t already have it!
Get a Phone with a Dual Camera
Phone manufacturers are aware that digital zoom is snake oil. For the discerning customer who won’t settle for less than the best, some phones do have optical zoom.
Well, sort of.
Manufacturers are ever-trying to build a smaller phone (even if nobody asked for it). There is certainly a premium on space inside every mobile phone, so fitting in a decent camera mechanism is a challenge. Fitting in a camera with a lens that can move to any appreciable degree is nearly an impossible task.
Enter the dual camera. You’ve noticed that the back of your phone has several little lens-y, lightbulb-y kind of things? If you’re particularly observant, you might have noticed that there are more of those than your phone from a few years back had.
Those are different cameras (and you were right about the light). Allowing for a movable lens would require giving the camera more depth in the phone, and you can’t have that. Instead, they just added another camera and lens with a different focal length. When you zoom in, the phone automatically switches to using the camera with the lens that will produce the best quality photo for that shot.
That’s pretty slick, huh?
Phones With a Dual Camera Setup
- OnePlus 6 (16MP rear camera with dual LED Flash, f/1.7 aperture, Sony IMX519 sensor, OIS, EIS and a secondary 20MP camera with Sony IMX376K sensor, f/1.7 aperture, 480 fps slo-mo at 720p, 240 fps at 1080p, 4k at 60 fps)
- Huawei P20 Pro has 3 rear cameras – (40 MP (RGB, f/1.8 aperture) + 20 MP (Monochrome, f/1.6 aperture) + 8 MP (Telephoto, f/2.4 aperture)
- Samsung Galaxy S9 (12MP dual-camera setup with f/1.5-f/2.4 variable aperture and 2x true optical zoom)
- Honor 9 Lite (13MP+2MP combo is available on the rear as well and front)
And more! With each generation of smartphones, more and more are adopting the rear dual camera setup (and sometimes even dual cameras on the front!).
Alternatives to Digital Zoom
Buying a new phone ain’t cheap, though, so we’ve come up with a couple of other products and techniques to get around using digital zoom.
Use an Aftermarket Lens with Your Phone
A phone camera lens is the obvious one. Phone camera lenses are becoming both more widespread and higher-quality. It’s not just a thing you hear about – lenses are things you see on the street.
As their popularity increases, so does the range of offerings. From cheap and straightforward telephoto lenses to high-quality telescopic lenses, phones have almost the whole range of lenses available to them that traditional cameras have.
Here’s a guide to some of the top lenses available to smartphone photographers. Here’s a great example of a telephoto lens that will offer optical zoom at a considerable distance:
Take the Full (Zoomed Out) Photo
This advice sounds lame, I know.
Still, it’s offered to you because Photos With Phones is big on improving your photography skill through restrictions on shots. Not being able to take a shot the way you want or expect to, forces you to think outside the box and develop new strategies to tackle the problem. Putting yourself in difficult situations is the only way to improve.
So, yeah, if your phone only can only do digital zoom, take the whole picture. You’ll have to play with the composition a little to get an appropriate substitute for the shot you wanted, but it’s okay if the subject is small. It doesn’t even have to be in focus. Photography is art.
Editing the Full Frame Photo
If you’re not entirely satisfied with that zoomed out shot, you can edit it. Remember – cropping is what your phone was going to do anyway if you tried to zoom in. You can experiment with cropping and find the point at which the resolution becomes unacceptably poor.
… Then probably back up a bit. What can you do with the photo? Reframe your perspective (and maybe the picture, too). There are many ways to edit a photo to reduce the negative impact of low resolution:
- adjusting contrast
- background or foreground blurring
- go for a retro look – adjust the saturation or hue
- crop it to just the subject then frame it with another image/background and text
Need an excellent photo editing app? Here are our favorites.
Digital zoom isn’t the end of the world. You just have to be aware if you’re using it and know how to work with it! What tips do you have for using digital zoom phones, or how do you implement optical zoom on your smartphone?