Why are the impacts of the smartphone camera so great?

Whether it’s the new Samsung Galaxy S21 Ultra, Apple’s iPhone 12, or the Huawei Mate 40 Pro, the protrusions on the camera case look bigger than ever. In fact, phones with larger camera cases often end up taking better pictures. Narrow phones, on the other hand, have fallen into the social hierarchy. Although this trend appears to have a positive effect on the quality of the photograph, it is not the most aesthetically pleasing compensation and makes phones more bulky.

When it comes to cutting edge mobile photography, it is impossible to escape the impact of the camera. But why? To understand, let’s dive a little deeper into the inner workings of the smartphone camera.

Here are some examples: Mega shootout: the best tested camera phones

Focal length, lenses and crop factors

Before getting to the heart of explaining the camera’s impact, we need to familiarize ourselves with some of the essential attributes and terms of all camera designs.

We’ll start with lenses and focal length. All camera lenses, from DSLRs to smartphones, focus on light entering the focal point, known as convergence. This focal point is where the image sensor is located to digitally capture your image. The focal length defines the distance from the lens to the focus point, measured in millimeters. However, in reality, complex layers of lenses mean that the actual length is usually less than that listed. However, the effect is the same.

Dive deeper: What is focal length in photography?

Simply put, the focal length defines the camera’s field of view and “magnification”. Longer focal lengths narrow the field of view and increase magnification. This results in a zoom effect. You can imagine this considering how the change in focal length changes the angle of view as light is refracted by the camera lens. See the image below as an example.

It is important to note that the focal length affects the perspective of the image as well. There is less visible separation and distinction between foreground and background objects at longer magnifications. See the apparent distance between the trees in the image above. Remember this, as we’ll get back to that later. This nuance has been the cause of many debates about OnePlus’ zoom capabilities in the past.

Explanation of the terms of the photograph: ISO, aperture, shutter speed and more

The other equally important part of this equation is the “harvest factor”. It is often confused with the properties of focal length. The crop factor of a camera depends on the size of the image sensor. Imagine looking through the camera lens. The lens captures an image regardless of the size of the sensor. Therefore, the final image captured by the lens is cropped depending on the size of the image sensor.

Note that a smaller image sensor has the side effect of producing a narrower cut and a narrower field of view. This creates a more enlarged appearance for full-frame images, known as focal length multiplication. This is one of the reasons why you will find small image sensors used in smartphone telephoto cameras. However, cropping does not have the same perspective effect as a native full-frame focal length at the same magnification. It is important to understand the crop factor, as it influences the fields of view of zoom and wide-angle cameras found on smartphones.

The search for larger sensors and longer zooms

With the concepts of focal length, magnification and crop factor in our curriculum, we can turn our attention to the trend for thicker smartphone camera cases.

See too: The best camera phones you can get

The first reason for larger camera boxes is the search for longer range zooms. As mentioned earlier, focal length is a key component of a camera’s magnification. Although complex lens structures can increase the effective focal length, in the final analysis, a greater distance between the lens and the sensor is required for zooms of greater distances. This requirement is the determining factor behind the use of periscope technology for cameras with long-range zoom without a major camera impact. They extend the distance from the lens to the image sensor using mirrors to reflect light. The trend towards longer telephoto zoom capabilities is almost certainly a factor in thicker camera overhangs.

The second factor that leads to the camera’s larger bumps is the desire for larger image sensors. These sensors improve light capture and image quality. Although the size of the sensor is related to the cutoff factor instead of the focal length, there are reasons why longer focal lengths may be desirable with larger sensors.

For starters, smartphones probably want to maintain the same picture frame and magnification as previous designs when switching to a larger sensor. Maintaining the same cutoff factor with a larger sensor requires a longer focal length. Otherwise, you end up with a wider field of view that may not be desirable. This is most important in the context of systems with multiple cameras, where defined magnifications are required between the configuration of the ultra wide angle, main and telephoto camera.

Read More: Why camera sensor size matters more than more megapixels

Finally, we need to consider lens distortion, which is usually more noticeable at the edges of the lens. Increasing the size of the sensor and using a larger cut of the lens can result in more noticeable distortion. This is more likely to be an issue with small, wide-aperture lenses used in cell phones. See the image below as an example.

High quality lenses can help here. However, they are notoriously difficult to build for compact smartphone formats and their very wide openings. An alternative solution is to adjust the focal length. Then, the field of view passes through the lens quality point closest to the center, where there is less chance of distortion. However, this again requires the use of a longer focal length and therefore a larger camera housing.

Likewise, consider the inverse requirements of wide-angle sensors. Larger sensors or shorter focal lengths are used to widen the cut and / or increase the field of view. That’s why you’ll notice a lot more distortion at the edges of your wide-angle images.

Why are the impacts of the smartphone camera becoming so great?

Although there is no single explanation for the increase in the thickness of the camera overhangs in recent years, there is a common theme. The trend comes down to smartphone camera designers fighting the laws of physics to improve camera features and image quality.

Related: What to expect from smartphone cameras in 2021

The desire for greater zoom capabilities and larger image sensors to close the gap in DSLR cameras are the two biggest factors driving the trend. It is no accident that smartphone cameras that offer industry-leading sensor sizes, zoom capabilities and image quality tend to feature larger camera bumps. While phones that offer more traditional camera features can maintain finer form factors.

Not to mention the demand for larger batteries, 5G antennas and several other bits of technology, all vying for a precious space within modern smartphones. There is simply no other option but to build thicker phones or larger cameras if you want all this technology.