There are devices that take 360º photos with a click of a shutter, but in most cases, we take several photos, partially overlapped, with an ordinary camera and use a stitching software to produce a panoramic photo.
A simple explanation for taking a 360º photo is to take several photos of about 30% or more overlapped horizontally (360º) or vertically (90º+90º), at a fixed position.
Shown below is an example of photos taken horizontally, vertically or at 45º. The number of photos you take depends on which kind of lens you use. If the angle of view is narrow, take many photos and if you use a wide-angle lens or fisheye lens, you can take fewer photos.
You can use various stitching programs to combine these photos and create a big photo with a length to width ratio of 2:1. Using a panoramic photo viewer, you can rotate the photo in all directions.
Principles of a 360º Photo
This photo is composed of several photos (about 10 photos).
After taking several photos overlapped, combine them into one image with a computer program.
To take a panoramic photo, you need a camera that supports panorama function. As shown below, such camera is made with different methods from an ordinary camera. It has a slit type lens system, so as a slit revolve, a line of light is recorded. Ordinary camera records a full shot at once.
This is the reason why a panoramic photo and an ordinary photo are taken using different methods.
A panoramic photo projects the images onto the surface of a cylinder, then unrolls the cylinder to make a flat plane, while a standard non-panoramic photo displays the images on a flat plane directly. If there is a rectangular object (ex. building), an ordinary photo shows it as a flat rectangle while a panoramic photo shows a straight vertical line and a curved horizontal line.
You can’t create a 360º photo by simply stitching ordinary photos together. It is possible but there is a huge chance the quality will not be as seamless as the original panoramic photo.
To transform an ordinary photo into a panoramic one, you should change the projection method. Change to panoramic mode first, and stitch the photos together.
Rules of Taking a Panoramic Photo
To take a panoramic photo, you should keep a few things in mind. The most important step is to keep a steady surface of rotation. You should fix the camera on a single axis and move it towards one direction, from one side to the other. The surface of rotation can be a horizontal line, vertical line or diagonal line. No matter which line you choose, you should fix the camera on one axis to prevent it from shaking.
Second, the photos you take should be partially overlapped. Overlapped photos will help the program identify the same spots to process. The best overlap ratio is about 20~50%. More than 50% overlap is not necessary and will only make the process complicated. Less than 20% overlap may cause errors. At least 10% overlap is essential to create a seamless panoramic photo.
To take a panoramic photo accurately, you should use a tripod to keep a steady surface of rotation.
Install the tripod and camera first. Do not fully tighten them. Spin the camera on the supporting surface to check whether the camera can smoothly move from side to side.
Take a photo at the first position, slightly rotate the camera to the right and take another photo.
Repeat this process until the end. If you rotate the camera to the left, you should change the order when you edit. The photos should be partially overlapped.
Make sure not to change the position of the camera on the tripod while capturing the scene. If you set the camera vertically you must maintain the position while capturing. Also, if the tripod is not set properly, take photos again to ensure you get clear images.