Optical vs. digital zoom method on smartphones.
If someone goes from the early days of mobile phones today, they might be confused that one of the most important features in our phones is cameras.
The early phone cameras were downright terrible, but the ability to carry your camera wherever you go quickly made them extremely popular. So manufacturers are investing a huge fortune in camera development, and now we have camera phones that can give professional cameras the opportunity to make their money. At least under the right conditions.
However, one thing that relatively few smartphone cameras currently have is optical zoom. Over time, however, you will start to see this in new phones. So now is the time to discuss the issue of optical and digital zoom.
What Is “Zoom”?
You probably already know what camera zoom is. At least you know what he does. “Zoom” is a function with which a subject in your photo, which is far away, appears nearby. The effect on a photo is to essentially reformat it, making the subject or person fill most of the space.
There are different ways to achieve this effect, but most smartphone cameras use a technique called digital zoom. To understand how optical zoom differs from the digital zoom method we currently use, we first need to explain the digital zoom, which is currently used in the vast majority of phones.
Everyone’s Doing It: Digital Zoom
Digital zoom is almost the same as cropping and resizing a photo in an application like PhotoShop. The main difference is that you do it live when you take a photo or shoot a video. So what’s the deal? It all comes down to pixels. Hence the “digital” digital zoom.
When you enlarge a digital image, it becomes more “pixelated”. This is because you have a fixed pixel headroom. The only way to enlarge is to make the pixels bigger. The image becomes grainy, uneven, and the result is a low fidelity image.
It sounds like a disaster for smartphones then, but smartphone manufacturers have developed various tricks over the years to make pixelation effects on digitally scaled images less problematic. Because modern phone cameras have sensors capable of picking up a lot more pixels than most people usually need. Thus, you can crop to the full sensor resolution part without loss of quality.
This is great if you want to take a photo suitable for social media, but if you want to take a photo in full camera resolution, you cannot enlarge any part of it without losing detail.
Most people probably don’t want massive full-resolution images that can’t be downloaded to FaceBook or Instagram in their true quality anyway. However, more and more people are taking smartphone photography very seriously. This means there is a market for more premium solutions. This is where optical zoom comes in.
Poon is completely deliberate.
Bending Light: Optical Zoom
Optical zoom is simply a zoom method that uses light to magnify an image. It works just like a magnifying glass by deflecting light through an optical medium (lens) to create a larger image.
In a dedicated camera such as a DSLR (digital single-lens reflex camera), you have large lens units that you can magnify by physically moving the lens back and forth. This changes the focal length between the lens and the camera sensor. Projects an enlarged image onto the entire sensor.
As you can probably tell from the way it works, this means that the magnified image projected through the lens covers the entire sensor at full resolution in light. This means that the zoomed image has as much detail as the full image from a digital zoom only camera. This is truly a lossless magnification.
Optical Zoom Is Hard in a Smartphone
Achieving optical zoom in a smartphone is not trivial. There can’t be a huge motorized lens on the back of a phone. Although in fact it was done. For example, the Samsung Galaxy S4 Zoom was essentially a smartphone with a compact digital camera glued to the back. Take a look at this:
Clearly, this is not something that you can just stick in your pocket, so this approach never caught on. Instead, modern smartphones simply attach a bunch of cameras to the back of our phones. Each camera has a different focal range, so when you put all the cameras together, you get an optical zoom range.
This is not the same as having, for example, a large telephoto lens on a DSLR. This is because you can change the focal length of a telephoto lens to focus an image at different zoom levels onto the same sensor. The problem is that most multi-camera smartphone settings have different sensors for each lens. The main camera usually has the largest sensor with the most pixels. With wide-angle and telephoto cameras with smaller and cheaper sensors.
Doesn’t that negate the point? This is true in a way, but the multi-camera setup still offers the best high-quality zoom range on a phone. Engineers have come up with ways to combine these different approaches to scale up something larger than the sum of its parts.
Best Of Both Worlds: Hybrid Zoom
The so-called “hybrid” zoom systems use the optical capabilities of onboard cameras along with digital zoom and so-called “computational photography”.
Computational photography refers to a suite of software techniques that use artificial intelligence and other bizarre mathematical techniques to modify and enhance the images that a camera can capture. For example, artificial intelligence can increase the resolution of an image by “imagining” how it would look at a higher resolution.
This may sound like magic, but it actually works very well in most cases. Such software techniques can also help you combine different images from built-in cameras to enhance photo details at the upper end of the optical zoom range. Even when digital zoom comes into play, all of these image data sources and intelligent software algorithms can create some pretty stunning images.
Should You Care About Optical Zoom In A Smartphone?
High-end smartphones like the iPhone 12 have a good optical zoom range. It’s actually not quite a telephoto, but in general, you can expect an image size increase of 2-2.5x without pixelation. This is ideal for typical use cases, such as photographing something close enough that you cannot physically get close.
It’s certainly a nice feature, but the vast majority of users will be completely happy with digital zoom. Especially when combined with a good dose of artificial intelligence. If phones start offering optical zoom ranges above 2.5x at the same resolution as the main sensor, it’s time to sit down and pay attention. However, at the time of writing, this feature should not influence your buying decision.
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Optical vs. digital zoom method on smartphones
Optical vs. digital zoom method on smartphones
- The A – Z Of Optical Vs. Digital Zoom