Body image stabilization (IBIS) is one of the main features of mirrorless cameras, such as the Canon EOS R5, Canon EOS R6, Nikon Z7 and Sony A7 III. But what is it, how does it differ from other types of image stabilization, and does it really matter at all? Let̵7;s find out!
What is image stabilization?
Image stabilization (IS) is also sometimes called vibration reduction (VR). It is a mechanical function of some lenses and cameras that limits the amount of blur caused by camera shake.
In general, the slowest shutter speed you can use without IS and still get blur-free images is 1 / XX, where “XX” is the 35mm equivalent focal length of the lens. This is called the mutual rule.
For example, if you use a 100mm lens, you can safely use a shutter speed of 1/100 of a second. With a 50mm lens, you can go a little slower in 1/50 second and still get acceptable sharp images.
IS, whether it is a function of the lens or the camera, allows you to use a slower shutter speed. Depending on how advanced it is and how stable your hands are, you will probably be able to go somewhere between two and four stops slower. (Some manufacturers, such as Canon, claim that some camera and lens combinations can have up to eight stops).
With a 100mm lens, this means a shutter speed between 1/25 and 1/10 of a second. In low light, it is enough to make a big difference.
IBIS against stabilization of lenses
The big difference between IBIS and lens stabilization is where the stabilization mechanism is located. With IBIS, the camera sensor itself moves slightly to counteract all camera shake. With stability in the lens, an extra lens element moves and ensures a stable image protection on the sensor.
No system is superior to the other – they both have their advantages.
IBIS works best with shorter focal lengths. On long focal length lenses, such as a 300 mm telephoto, the sensor cannot move enough to overcome the greatly magnified camera shake. However, since the stabilization is done in the camera, all lenses can be stabilized – even those that were not originally designed to be.
Stabilization in the lens is less convenient and more expensive than IBIS. While longer lenses with IS have systems designed to accommodate a lot of shaking, you pay a premium for each lens. It is also another fragile thing that can break if you accidentally drop a lens.
How much does it mean?
Historically, Canon and Nikon have relied on lens stabilization for their lenses. It is only with the launch of their latest mirrorless cameras that they have started using IBIS. This is largely due to the fact that Sony has done a lot about IBIS in its mirrorless camera area.
IBIS is really a nice feature to have, and it can allow you to take pictures you would otherwise miss. But just like any image stabilization, the following important warnings come:
- It only reduces blur from camera shake: If you use a slow shutter speed, like 1/10 of a second, you can expect to get motion blur from anything moving in the frame, even without the camera shaking.
- It is most useful on longer lenses, but works best with shorter focal lengths: This is not a magical solution for wildlife or sports photographers.
- You get better results by increasing your ISO or aperture: In most situations, this strategy is more reliable than image stabilization.
It is also worth noting that many of Canon’s and Nikon’s new telephoto lenses still have built – in IS, which works with IBIS to stabilize images. This means that you basically pay twice for stabilization.