This content is offered by Samsung and produced by Humanoid xp
If you are on a family WhatsApp group, you have inevitably come across one or more photos that look like piles of degraded pixels, badly framed and often blurry and which are always accompanied by the famous comment: “So what do you think? It’s beautiful isn’t it? If you are the polite type (and for the sake of household peace), you will answer yes. If you’re not afraid to take on your family, it’s time to teach them how and when to use their smartphone zoom.
These overly pixelated and poorly detailed photos were often taken with the zoom of the phone’s camera app. Poor quality photos which is simply explained by the fact that the zoom of a smartphone is not as powerful as a real optical zoom of a camera.
There is zoom (optical) and zoom (digital)
In this article, we will not go into technical details. If there’s one thing to remember, it’s that in the vast majority of cases, smartphones are pretty bad when it comes to going beyond × 3 or × 5 zoom. It is a problem of space: an efficient zoom without loss of quality physically requires space. It’s not for nothing that camera lenses exceed so much. Space, precisely, there is little in smartphones whose thickness now rarely exceeds a centimeter.
On a smartphone, as on a camera, there are generally two types of zoom:
- Optical zoom : in this case, a lens above the photo sensor will magnify the scene. This type of zoom is optimal, because the photo is very little or not at all degraded.
- Digital zoom : here, we will directly crop the photo taken with the sensor and the base focal length. The advantage of this type of zoom is that it allows you to go very far in the magnification, with the counterpart of considerably degrading the image by zooming more and more.
On recent high-end smartphones, equipped with several photo sensors, the photo module often includes a classic “wide-angle” main sensor, which will serve as the basis for digital zoom. These are sensors that take photos in very high definition, which allows you to make clean “cutouts” in the photo when you want to zoom in on it afterwards. This is what the Galaxy S20s do for example with their zoom.
These smartphones also (sometimes) include a telephoto lens, a sensor with a lens that allows it to perform a true optical zoom (often × 2 or × 3) without losing image quality. Here, the image is then naturally magnified by lens, so the photo taken does not lose quality. This is the case of the Galaxy S20 Ultra, for example, which has a telephoto lens capable of zooming losslessly up to × 4.
On the Galaxy S20 Ultra, as on other smartphones equipped with telephoto lenses, once the user exceeds the maximum zoom of optical magnification, the phone will then automatically switch to digital zoom. This is what explains why the quality of high zooms on smartphones can seem poor.
How to use the zoom of Galaxy S20?
On the Galaxy S20, there are two ways to use the zoom on the photo app. The first is to use the forest, tree and leaf shaped icons at the bottom (or right) of the photo preview. They correspond to zooms × 0.5, × 1 and × 3, respectively. By clicking on these icons, the smartphone will automatically zoom in or out on these zoom values.
To zoom in or out directly in the image, simply “pinch” the preview of the photo with two fingers. But it’s easier (and more stable) to slide your finger over the three preset zoom icons. Automatically, a slider will appear indicating the zoom level you are at. Below this ruler are also preset zoom buttons, ranging from × 0.5 (ultra-wide-angle) to × 30 (the maximum zoom of the Galaxy S20).
Some tips to improve your zoomed photos
Here are some basic tips for improving your photos when using the camera zoom.
- Often, it is better to take a photo without any zoom, then crop it yourself afterwards in the gallery to zoom in on the desired element. We have explained in this article how to easily crop your photos with Samsung’s Gallery app.
- If you still decide to use the zoom, try not to go any further than the × 5 zoom. Beyond that, the quality will be felt.
- If your smartphone is equipped with a true optical zoom (telephoto), pay attention to the ambient light when taking your photos! These sensors need light to be truly effective. The low light will only add extra noise to your photo.
- Finally, stabilize your smartphone on a wall or against your body. By definition, the zoom is sensitive to the slightest movements you can make. To stabilize it well, the solution is to frame your scene well with the zoom, to set up a self-timer of a few seconds and to stabilize the smartphone well while waiting for it to fire.
So when should you zoom in and when shouldn’t you zoom in?
The answer is quite simple: on a smartphone, use the zoom in moderation. Understand: beyond the × 3 or × 5 zoom, the image quality deteriorates rapidly and we do not recommend that you zoom further. To illustrate our point, we took several photos with the Galaxy S20 +. We started with the main sensor, without any zoom.
Then with the × 2 zoom. In terms of rendering and quality, the photo is still excellent and quite usable.
With × 4 zoom, the quality begins to deteriorate slightly. We are starting to lose a bit in detail, in sharpness.
Things start to go wrong right from the × 10 zoom. But even if the photo loses detail, the laps displayed here two kilometers away are still sharp!
With × 20 zoom, the picture becomes ugly. We are starting to see the pixels, the sharpness is no longer there.
Finally, the × 30 zoom barely allows you to read the logo. The rest is very scrambled, very noisy. From an artistic or photographic point of view, the photo has no interest. From a technological point of view, however, we have to admit that this is really impressive.
As with the flash of a smartphone, the zoom has above all a “practical” utility. Essentially, you’ll be using it to take a sticky photo, not to post the result on Instagram.