Electronic image stabilization (EIS) is a form of digital image enhancement that can help to improve the outcome of photographs and videos created using digital cameras and smartphones. For images, this means that you can minimize blurring while taking photos without a tripod or stable surface. Meanwhile, for video, it can help to reduce the physical shakiness of the footage and thereby help to make it easier to follow the subject.
In this post, we’ll take a look at how EIS works, differences from optical stabilization, and how and when you should use it in your own photography and videography.
EIS vs OIS
So how precisely does electronic image stabilization work?
Electronic image stabilization is stabilization provided by the software within the camera when an image is processed. This is in contrast to optical stabilization, which works by using mechanisms inside the camera rig (a prism that moves in front of the lens) to correct the image before it ever reaches the sensor to prevent it from shaking around even when the camera is moving quickly.
But that is not to say that electronic image stabilization doesn’t also rely on hardware. Here, gyroscopic sensors that are able to detect movement and orientation are used inside the camera and that information is then fed back to the camera software. The software will then be able to analyze the information collected by those sensors and compare it to the footage. From here, movement and shake can be eliminated simply by cross referencing the accompanying movement. If the camera moved slightly left suddenly for instance, then the footage can be corrected to remove a sudden jerk in that direction.
EIS often standard on many phones because nearly all smartphones these days include sensitive gyroscopes already in order to handle things like orientation changes and tilt-controls in games. As ‘neural chips’ become more commonplace in consumer handsets and computer vision improves, we can expect the software side of things to improve here too.
EIS for Still Images
For still images, image stabilization can be used to remove blur while taking photos by hand rather than with a tripod. The camera may adjust a single image or this might also be achieved by taking multiple photos and comparing the images to remove the motion. This can be useful when using a slow shutter speed (long exposure) or when opening up the aperture in order to get wide angles or shallow depth of field effects. Typically, we use longer exposures when trying to capture low-light photos (leaving the lens open for longer allows more light in, in order to better brighten up a dark scene) or when trying to create intentional blur but only for a moving subject.
While using image stabilization can be a useful trick for this kind of photography, it can only do so much. No algorithm is perfect in this regard and the better option will always be to steady the camera where possible. That means using a tripod if possible, or potentially even resting your camera/phone on a wall or on a friend’s shoulder.
Another option is to try reducing the shutter speed and aperture as far as possible while still capturing as much light as possible for silky waterfall shots or low-light photography. A photographer dedicated to their shot will likely try all those options in order to get the perfect picture, while also considering things like the composition of the shot and the story they’re trying to tell.
If you are going to be taking photos while running, or from the window of a moving train, then keeping the shutter speed minimal is the preference – as is looking into using a gimbal.
Using optical stabilization will help to maintain the image quality better, seeing as all of the information coming through the lens will be used (there will be no cropping) and seeing as you won’t be relying on imperfect algorithms. That said, there is only so much that a moving prism can do to correct a very jerky hand!
EIS for Video
For video, the ideal preference for stabilizing the shot will always be to use an accessory like a gimbal. These are the tools used by professional videographers that involve suspending the camera on a long arm so that it is held straight and still and all movement is neutralized. Compared with EIS or OIS, this can make a profound difference. This way, you can film while running or walking and still have a smooth, pleasant shot.
If possible of course, it’s still always best to eliminate the unwanted movement completely and to place the camera on a tripod with a panning head to move smoothly.
Failing that, either optical or electronic stabilization can do a good job when combined with a steady hand. In this scenario, most video EIS tends to work by cropping the video being taken to give buffer to remove jerky actions. Unfortunately this tends to work a less reliably than it does for still images and because the footage is moving, the occasional warping can occur less noticeable.
Ultimately the effectiveness of any electronic image stabilization will rely on the sensors and software built into the camera. We recommend to minimize any extra motion wherever possibly by using a gimbal or tripod rather than relying on the camera to adjust to unpredictable motion. In a pinch or when other options are not available EIS can help to sharpest image or video, but do not use it in combination with a tripod or gimbal as it may cause correction that is not necessary.