When choosing their future smartphone, buyers value three features: the screen, the battery and the camera. In the age of selfies, the camera is increasingly coming to the fore, at least in the minds of manufacturers. That’s why they constantly improve it. But sometimes too much is like not enough…
There’s nothing quite like the launch of a new phone by a global tech giant than… the launch of a phone by one of its competitors. In a few minutes we praise the brightness of the screen, the number of pixels found there, the ability to use the device for hours before the battery needs to be charged, and then… we spend the next hour praising the sensor and the to describe in detail the lenses his cameras are made of.
As a sign of the times, manufacturers are now integrating some of their phones with a front camera whose sensor is more efficient than that of the rear camera. Or they present their flip-screen phones as the ideal way to take the best selfies: you can point the phone’s most powerful camera at you and see the frame on the screen in real time.
Pixels that are… mega
For a while, major electronics brands touted the high pixel count in photos taken with their phones. Each pixel is a point of light that is captured by the digital sensor and recorded in the resulting JPEG file (or RAW for those familiar with Photoshop).
Other high-end cameras have digital sensors that reach 100 megapixels. 100 million points of light that make up each photo. That is much ! Most of the time it is also unnecessary. We rarely need so many pixels.
For example, if you print a photo on photo paper, you actually only need about 300 pixels (or “dots”) per inch, the (imperial) measurement used in photography and graphics. If you need to print a 6 x 8 inch (15 x 20 cm) photo, the math is simple: you need an image that is 1800 pixels high and 2400 pixels wide. It will have 4.3 million pixels.
Photos taken with a phone very rarely end up spread out on photo paper. We see them more often on a screen whose density is less than 300 pixels per inch. We don’t need a 100 megapixel sensor for this.
This means that the more pixels you capture, the more you can improve your photos. Both Apple, Samsung and Google combine data from multiple pixels to improve the sharpness of the image, its colors or other of its characteristics.
A phone equipped with a 48-megapixel sensor could produce photos that end up being just 8, 12, or 24 megapixels.
Zoom-Zoom
To date, mobile phones are not able to perfectly reproduce the variable focal length telephoto lens. In one word (English): Zoom. With automatic cameras, it was this little wheel that you moved with your index finger to frame your subject more accurately.
In cell phones, several lenses arranged next to each other are used to compensate. The Samsung Galaxy S23 Ultra has five. The iPhone 15 Pro Max, which Apple unveiled this week, has three, but they are configured to create the illusion that the phone has seven.
One of the lenses on the iPhone 15 Pro Max is very special: it creates a “5x zoom” effect that is equivalent to a 120mm telephoto lens. Like Huawei and Samsung before it, the Californian manufacturer had to curve it like a periscope (mirrors and all) to fit into its phone.
The 120mm focal length of the Apple lens is specifically designed for portraits. Professional photographers who specialize in weddings like to use this type of lens with a focal length of 120 to 135 mm.
Photographers looking for rare animals prefer a longer focal length, which can be up to 400 or even 600mm. Samsung offers image magnification on its S23 Ultra that simulates the effect of a 100x telephoto lens, which is huge. But the resulting images are mostly blurry or “pixelated”, where we can clearly see the automatic retouching carried out by the phone’s algorithms.
But we’re not there yet. While you wait for a phone with a true vari-focal telephoto lens, you’ll have to choose between phones whose cameras are getting bigger and bigger