‍

360° cameras continue to grow in popularity as they become better in quality, and more affordable in price. With latest releases from innovative companies such as Insta360 and LabPano more and more people are drawn to the unique capabilities of 360-degree cameras.

So… how do 360-degree cameras work?

‍

360-degree cameras work by capturing an entire panoramic view in a single instant.

Standard cameras, like the one on your smartphone, typically have a field-of-view, or the area that is visible through the camera, of about 60-90 degrees. Even a “wide angle” lens generally covers only 100 degrees or so.

360-degree cameras typically have multiple, wide-angle (“fisheye”) lenses arranged in a carefully designed circular geometry, which allows them to capture a complete panoramic view with a single synchronized exposure. Different manufacturers use different hardware designs, with two major design approaches.

Two-lens 360 cameras, such as the one provided in the Avatour hardware kit, offer a very straightforward solution. They utilize two ultra-wide fisheye lenses, one on each side of the camera, each typically covering about 200° of the visual field. The lenses work together to cover the entire 360-degree field on two 180–degree opposed frames. This is the simplest and cheapest 360-degree camera design, and also enables the most compact device. However, cost-effective image sensor chips are generally 4k, or 3840x2160, so most two-lens 360° cameras are limited to 5.7k resolution. Also, because of the lack of parallax, two-lens designs are unable to capture stereoscopic (3D) content. (Yes, there’s a difference between 2D and 3D in 360 capture! This is a topic for another day.)

Multi-lens 360 cameras are more complex and expensive than their two-lens brethren, but offer the potential of much higher capture resolutions - as high as 20k - and the ability to capture stereoscopic 360° images and video. They also typically require extensive post-processing of capture due to the difficulty of “stitching” the many images.

Two-lens 360 cameras are best suited for most business and consumer applications, including 360° videoconferencing, remote inspections, virtual tours, and process training, while multi-lens cameras are typically used only by professional 360-degree videographers.

‍

360-degree cameras work by ”stitching” and “stabilizing” the capture from multiple sensors.

Whether captured with two or more lenses, 360-degree content must typically be “stitched” and “stabilized” before it can be used. These are computational processes that some cameras can process in real time, while others require a separate post-processing step on the camera itself, or on a connected mobile device or computer.

”Stitching” is the process of lining up the images captured by multiple sensors to create a single spherical image, with a seamless blend where the various captures meet. All 360-degree cameras capture a certain amount of overlap between the separate lenses - usually between 10-30 degrees of the visual field - to enable a good stitch. But it is mathematically impossible to have a “perfect” stitch due to the parallax between the two lenses. (You can visualize the problem by looking at a scene with objects at multiple depths, and then closing one eye and then the other.) So all stitching algorithms make compromises in one way or another; the most computationally complex approaches will make nearly any stitch look good.

After stitching, 360° videos are usually also “stabilized.” This process compensates for any rotation of the camera, and makes sure that the horizon is stable. In some ways this is similar to a gimbal on a standard ”flat” video camera, and makes the captured footage much more useful.

Finally, the 360-degree content is “projected” to a flat format for distribution.

Stitching and stabilization are processed in spherical geometry, but since there are no spherical distribution formats for images or video, the content must be converted to a standard flat image format for use.

There are several different “projections” available to map a 360 sphere onto a standard rectangular image frame. The most common and most widely-compatible format is called an “equirectangular projection” (ERP).

Here’s an example of this projection:

‍

‍

The equirectangular projection is quite similar to the familiar Mercator projection that is used to display the map of the world, and shares some of the same benefits and drawbacks. Notably, the ”poles” - the areas at the top and bottom of the sphere - are heavily distorted, with relatively small areas appering much bigger than they are in life.

Images and videos in this format can be displayed on a variety of devices, including smartphones, computers, VR headsets, and even immersive rooms like the ones available from our partner Igloo Vision. Read more about the Avatour x Igloo Partnership here.

Some of the most commonly used 360-degree cameras on the market today are:

Insta360 One X2

Insta360 One R

Ricoh Theta

GoPro Max

Theta z1

‍

360-degree content in Virtual Reality

As virtual reality headsets have become more accessible, it has also become the preferred method of consuming 360° content. Viewers can experience a more immersive, and much more realistic experience in VR than on a computer, tablet, or mobile device.

This level of immersion has opened new possibilities in VR, especially with the release of the much anticipated Apple Vision Pro headset, set to release in February 2024.

(Check out our article on our first impressions on the Apple Vision Pro)

Experiences such as live concerts, and virtual tourism became popular, especially during the Covid pandemic, and we anticipate these experiences will only grow in popularity in the future.

‍

‍

‍

360-degree cameras are enabling new business applications

360-degree cameras and their unique ability to capture an entire space and surroundings have brought on many new opportunities and applications for businesses across industries. These use cases go beyond the typical 360° tours you may see of your local business, but more sophisticated solutions such as 360° Video Conferencing, Digital Twins, Remote Inspections & Audits, Live Virtual Tours, Remote Training, and more.

‍