Many people know the problem: You want to take a few quick photos, but the lighting conditions are poor. Without a tripod and handheld, even the pros can’t get shake-free shots under such conditions. In such cases, an image stabilizer can help. But how does the technology behind it actually work? In our article we reveal the secret of the image stabilizer.
The idea of stabilizing images dates back to the late 1980s. At that time, the first compact camcorders celebrated their first triumphant advance in homes. Spurred on by ambitious videographers, camera manufacturers developed the first solutions to make filming smoother even without a tripod. The image stabilizer was born.
When filming, shots blur at close-up. Everyone shakes imperceptibly. Especially in zoom shots, this shaking becomes extremely visible. That’s why experts in the development labs of camera manufacturers have been working on technical ways to counteract shaking. However, the development towards the image stabilizer as we know it today took some time.
First solution: Intelligent lenses
The first image stabilizer worked in the lens of the video camera itself. To do this, developers built an additional, movable stabilizer lens into the lens. This lens is controlled by a small motor.
During filming, this lens corrects minor shake caused by human tremors. The lens takes the incident light rays as its scale. Deviations are immediately detected and compensated for by moving the lens in the opposite direction accordingly.
The whole process, of course, takes no longer than the blink of an eye. It is therefore also clear that larger blurs cannot be compensated for with this method.
Incidentally, the first image stabilizers in lenses did not appear in photo cameras until the mid-1990s. Here, too, the technical development was first brought about by passionate amateur photographers. Spurred on by more and more small, compact SLR cameras, people discovered their love of photography.
When taking pictures, images blur if the subject is not properly illuminated and therefore a longer aperture time is necessary. The longer the aperture is open, the more noticeably even the smallest movements affect the quality of the shot. Here, too, the principle described above helps to stabilize images within the lens.
Further development: electronic image stabilizers
The advent of digital single-lens reflex cameras in particular changed the technology for making images shake-free. Inside the digital camera is an electronic image sensor. Similar to the stabilizer lens in the lens, the image sensor is mounted so that it can move. This allows it to move along up to five different axes.
To give you an idea of how fast the image sensor can move: The sensitive sensor compensates for wobbling movements up to 1000 times per second.
However, even the electronic image stabilizer built into the camera can only compensate for the smallest shaking movements. Extremely blurred pictures can then at best be justified with artistic freedom.
Master class: the dual image stabilizer
There are now photo and video cameras that intelligently combine both technologies. In this case, the stabilizer lens in the lens and the electronic image sensor in the camera work together. This method currently delivers the best shots when no tripod is available.
However, only a few camera manufacturers offer such a solution. Unfortunately, the different systems cannot be combined with each other. Therefore, you have to choose a manufacturer in order to enjoy razor-sharp pictures even under difficult conditions.
However, the best image stabilizer is of no use if the subject is moving extremely fast. In that case, the camera should have a sports mode that optimizes the aperture time for lightning-fast subject movements. Manufacturers of action cams, for example, offer such solutions – such as DJI or GoPro.