Smartphone cameras are becoming more and more capable by the day, with the world’s leading smartphone manufacturers constantly working to one-up each other. One of the smartphone’s camera features that is often talked about and improved upon is the camera’s zoom feature. More specifically, smartphone cameras are getting closer and closer to having a true optical zoom, but are they there yet?
Smartphone cameras do not yet have true optical zoom, in that the glasswork within the camera of a smartphone is not capable of moving in order to adjust zoom. Instead, smartphones have multiple cameras with different focal lengths and use these together to closely mimic optical zoom.
While smartphone cameras do not have a true optical zoom like DSLR and point-and-shoot cameras do, they are able to very closely emulate the effects of an optical zoom by way of using multiple camera lenses. Additionally, smartphone cameras, of course, have a digital zoom, and some are using hybrid zoom as well. In order to better understand the differences between all of these zoom features, let’s talk about each in a bit more detail.
What Are the Different Types of Zoom?
In the world of photography, there are three primary types of zooms, all of which have unique distinctions that differentiate themselves from the others.
- Optical Zoom – When it comes to DSLR and point-and-shoot cameras, this discussion is slightly less relevant as nearly all cameras of this type are equipped with optical zoom. Additionally, almost all current smartphones on the market have a dual-camera system that can closely emulate the effects of optical zoom (we’ll talk more about how that works later).
- Digital Zoom – However, if you have an older smartphone and haven’t yet upgraded to the newest models, you may still only have a camera with digital zoom.
- Hybrid Zoom – Additionally, many newer smartphone models are equipped with hybrid zoom, which is a combination of both optical and digital zoom. Hybrid zoom only works on multi-lens cameras and zooms by choosing the lens with the inherent zoom closest to what is desired by the user, and then fine-tuning digitally. As we learn more about the inner workings of both optical and digital zoom, you’ll begin to see why this can be beneficial.
So, let’s go over the differences between each type of zoom, and how you can tell which type of zoom your smartphone camera has.
Optical Zoom
According to Gear Patrol, optical zoom works by making physical, mechanical adjustments to the glasswork within a camera lens. A camera lens that is equipped with optical zoom is equipped with the hardware necessary to do this, whereas cameras with other types of zoom are not.
This manipulation of the glass within the camera affects zoom by adjusting the amount light that enters the camera, creating a zoomed in or zoomed out perspective, depending on what the photographer is trying to do.
Optical zoom is widely agreed upon to be the best type of zoom available and is the type of zoom that you’ll want to be using if you are trying to zoom in without any loss in image quality. In other words, optical zoom is the best type of zoom because it is lossless; this means that photographers can zoom in without losing any image data or pixels.
A photograph is nothing more than a series of pixels, and, generally speaking, the more pixels there are, the higher quality the image will be. Other types of zooms lose pixels when they zoom in, decreasing the quality of the picture being taken. Optical zoom, however, does not lose pixels when it zooms in, which is what we mean when we call it lossless and is why it is widely considered the best type of zoom.
While optical zoom is the clear winner in terms of photo quality and ability not to lose pixels when used, there are some limitations with it, especially as it is applied to smartphones.
The primary limit of the optical zoom is the fact that you need to have a relatively advanced lens in order to make it work, which means that a lens with true optical zoom will be expensive, which is not conducive to a strong product offering in the very competitive and already very pricey smartphone market.
Another limitation is the amount of space that is needed within a lens for optical zoom to work. In order for a lens to have true optical zoom, it must be large enough to allow the glass to move enough to actually get meaningful levels of zoom. With current technology, this is very difficult to do with smartphones. Smartphone buyers are looking for something sleek, and a large camera bump attached to the back of the phone will simply not work.
Digital Zoom
The next common type of camera zoom is called digital zoom, and it is distinctly different from optical zoom in the way that it works to create a zoomed-in image.
As we discussed, optical zoom lenses actually move the glasswork within the camera in order to manipulate how the light rays hit the camera sensor, which affects the perspective, i.e., the closeness of the image. However, with a digital zoom camera, the actual hardware within the lens does not move at all, no matter how much you adjust the zoom. You will see a zoomed-in photo as you zoom, but the camera lens itself stays put, so how does it do this?
In effect, the digital zoom is nothing more than your phone actively cropping an image as you zoom in. Basically, the phone will take the same picture, regardless of how zoomed in you are, and it will just crop the image according to how zoomed in you want the photo to be.
What this means is that the more you zoom in, the lower the quality the image that you’re taking will be; this is because the phone will crop out the parts of the image that are not within your zoom, which means that it will be losing pixels as well. The result is a photo that is of much lower quality than a picture with identical framing taken with an optical zoom lens.
You can see for yourself the effects that zooming has on image quality when doing so digitally. If two photos with identical framing are taken, though one is with digital zoom and one is taken by actually moving closer to the subject, the zoomed image will be of far worse quality than the photo that was captured closer to the subject.
For this reason, it is generally advised that people looking for a high-quality image do not use digital zoom, or do so wisely and with as little zoom as possible. In fact, Android Authority recommends not using digital zoom at all. Instead, they recommend taking the picture at 1x zoom and simply cropping the photo later to create a zoom effect. This way, you can actively track the photo’s degradation, and do your best to use as little zoom as possible in order to minimize it.
So if digital zoom yields lower-quality photos, why is it used? The simple answer is that it is, assuming the phone only has one camera lens, as many older phones do, the only option. It is the only type of zoom that the small size of a smartphone allows and is thus the only choice for single-lens smartphones.
Hybrid Zoom
The final zoom type that we need to discuss is called hybrid zoom. As you may have been able to guess by the name, the hybrid zoom is a combination of the above two zoom types that we’ve already mentioned. Hybrid zoom is only possible on smartphones that multiple cameras though, as it needs to use both to mimic optical zoom, and then adjust the fine-tuning of the magnification using digital zoom.
Hybrid zoom works by selecting the lens with the inherent magnification that is closest to the magnification level that the user selects, and then finishes the zooming digitally.
This process is best explained using an example: let’s imagine that a smartphone user is trying to take a photo at 3.5x zoom, and their phone has a camera with two lenses, a 1x lens and a 3x lens. In this instance, the phone will select the 3.0x lens, which means that it can do about 85% of the zooming without losing any pixels, which is great for image quality.
Then, it does the final 15% of zooming digitally to get all the way up to 3.5x zoom, losing only a small number of pixels and thus image quality in the process, because much of the zooming was done “optically.”
How Smartphones Mimic the Effects of Optical Zoom
We put the word “optically” in quotation marks just above for a very specific reason. This is because smartphones do not yet have a true optical zoom as a result of the amount of space that is required for true optical zoom to work within a lens. Instead, smartphones use their multiple cameras in order to very closely emulate the effect of optical zoom.
We touched on how they do this briefly in the example above, but let’s break it down in a bit more detail now. Smartphones have multiple cameras that have varying focal lengths, which are important factors in how modern smartphone cameras zoom. There are three different primary categories of focal length for smartphone cameras:
- Ultrawide: ~13mm
- Wide: ~26mm
- Normal/Telephoto: ~52mm
Those above listed focal lengths are off of the iPhone 11 Pro (the one with three camera lenses), and the focal length within each category will vary from phone to phone, but stay within a range close to those above-listed numbers.
These different focal lengths are essential to understand because zoom is a direct function of focal length. The higher the focal length, the more zoomed in the image will be. The important thing about this as it relates to smartphones though is that each lens will have a different focal length. This means that when a user selects their zoom setting, the phone can decide which camera has a focal length whose zoom is closest to the zoom that the user is requesting.
So, when some say that smartphone cameras have “optical zoom,” they are actually referring to the camera’s ability to choose between these different lenses in order to match the zoom level requested by the user. There is no physical movement of glasswork within the lens, so it’s not true optical zoom, though it is gaining zoom by using hardware rather than software, so the term optical zoom can only loosely be applied to this process.
How to Tell What Type of Zoom Your Smartphone Has
After all of this discussion on the different methods that smartphone cameras can use in order to zoom in, you may be left wondering what type of zoom your smartphone camera has. Luckily, this is quite an easy thing to find out.
The simplest way to find out what type of zoom your smartphone camera has is to simply take a look at the camera arrangement on the back of your phone.
If the camera setup includes more than one lens, then it is likely that your smartphone’s camera has the ability to do the pseudo-optical zoom that we talked about, as well as digital zoom. If your smartphone is newer, it is also likely using some form of a hybrid zoom as well.
However, if you take a look at your camera setup and find that there is only one lens on the back of your smartphone, then you very likely have a camera with digital zoom alone. This is because in order to have anything but the digital zoom on a smartphone camera with just one lens, you will either need to have a huge camera lens bump or have multiple camera lenses.
How to Make the Most Out of Digital Zoom
Smartphone manufacturers have almost entirely moved away from single-lens camera setups in recent years, as consumer demand for a smartphone with fantastic image quality has sharply risen. However, if you have yet to upgrade to the newest, latest, and greatest smartphones with an advanced multi-lens camera setup, you may be thinking that you’re out of luck when it comes to taking good photographs.
If you’re trying to take high-zoom photos only, then we regret to report that you may actually be correct. It is very difficult to get a high-quality zoomed-in image with digital zoom alone. However, there are a number of different tips and tricks that you can use in order to avoid having to use zoom in the first place, thus avoiding one of your camera’s biggest sore spots: digital zoom.
Move Closer to the Subject
Zoom is generally used for one of two reasons on smartphone cameras:
- The lesser common reason is that the user wants to alter the perspective of the photograph by using a different focal length. Adjusting focal length will affect how the photo looks, and certain focal lengths may be preferred for compositional reasons.
- The other, more common reason that zoom is used is because the subject is too far away. If you have a high-quality optical zoom setup, then using zoom is a great way to remedy this. However, if you only have digital zoom, you probably want to avoid using this too much. This can be done by simply moving closer to the subject.
You don’t have to move so close that absolutely no zoom is required at all, but it would be wise to move as close as you can and use as little zoom as you can, as you will lose fewer pixels by doing this and end up with a higher quality image.
Shoot at 1x and Zoom in Later
This may seem a bit counterintuitive: if you want a zoomed-in photograph, shouldn’t you just zoom in while you’re taking the picture? Again, if you have an optical zoom, yes! If not, then it may best that you don’t.
Instead, an excellent option to avoid the use of your camera’s digital zoom is to take the photo without using any zoom, and then simply edit the photo later and crop it however you like, emulating the effect of zoom.
While this will not result in any less pixel loss, it will allow you to more carefully adjust the cropping in photo-editing software, rather than having your phone do it for you on the fly. In the end, the goal of this is to crop out as little of the photo as possible, and it’s easier to see exactly how much cropping/zoom is needed afterward as opposed to while you are actually taking the picture.
Final Thoughts
As you can see, the concept of camera zoom is actually quite complex, likely more so than you had originally thought. And while all of these different options can be difficult to conceptualize as a smartphone shopper, modern smartphone manufacturers have actually made it quite easy by equipping nearly everything with a multi-lens camera. This means that if you’re buying a brand-new smartphone, you’re probably getting a fairly high-end camera as well.