Ever since we have had video recording on the iPhone, people have been wishing they could record in portrait while keeping that widescreen video. Just about everyone has, at some point, recorded a video in portrait and regretted it later. You would think it would be simple enough for these devices to just allow landscape recording while in portrait, but it is a bit more difficult.
A camera, be it in a phone, tablet, computer, or the traditional video camera, consists of two major components necessary to take a video. The first is a series of lenses that focuses the light into a manageable beam. The second is the sensor that captures that beam and sends it off to be turned into the final image you see.
The lenses that make up the camera’s optics are generally circular. This might be what leads many to believe that it would be a simple fix to have video recording in portrait. However, these lenses are round because it saves effort in manufacturing, decreases light distortion, and improves the camera’s aesthetic appeal. These lenses do not dictate the sensor’s ability to collect information.
The sensors in these electronics are actually rectangular. They are, in fact, the same aspect ratio as the final image or video that is taken. (Traditionally, it’s 16 pixels wide for every 9 pixels high, or a 16:9 aspect ratio.) When you turn your phone to portrait, it is like getting any other camera and turning it sideways. Due to the fact that the sensor is now taller than it is wide, your photo or video will also have to be taller if you want to keep all of the data that the sensor receives. This is what forces the video to be at a 9:16 aspect ratio while recording in portrait.
For the manufacturer to fix this problem, it would have to make the sensor a square instead of a rectangle. This way, the final image could be cropped to the desired aspect ratio. In the instance of 1080p video, the sensor would record in 1920×1920 and the top and bottom of it would be cut off to get it down to 1920×1080 or 1080p. The reason that manufacturers today do not do this is because of the increase in size of the camera, the increase in the necessary power for the image processor, and the increase in manufacturing cost. Manufacturers have to weigh the pros and cons of each and they normally decide that it would be better if they saved some money and took away one small feature.
A square sensor would add to the price of a phone or other device with a camera. Because of this, I would agree with the decision that the companies have made to stick with a rectangular sensor. The feature is not something that would convince me to buy one phone over another, and the companies kept that in mind when making their decision to exclude it from today’s smartphones.