Why so little in body image stabilization?

mosswings wrote:

I think that you're confusing avoidance with need. As long as the camera has a flippy mirror, in-lens stabilization offers advantages in both composing and in AF settling (i.e., shutter delay) that sensor-based stabilization doesn't. If you haven't attempted to handhold a long telephoto without framing-phase stabilization, you don't understand the very real benefit this offers, particularly for those without rock-steady muscles.

One also has to remember that system camera marketing is all about legacy support, and stabilization was invented in the film era. Try moving a strip of film around at the rate necessary for useful stabilization. It was easier to move an optimally placed lens element. System established; it will not change unless Canikon are willing to tick off their legacy lens users like Canon did when it went to the EF mount.

In the mirrorless age, the differences between sensor- and lens-based stabilization diminish greatly. framing-phase stabilization now is a matter of course, but there may still be some lingering impediments to AF settling. This is becoming a smaller and smaller issue as sensor readout rates and processing power increase.

One also needs to consider the effect of sensor size on the efficacy of sensor-based stabilization. The smaller formats require less absolute sensor motion to accomplish similar levels of stabilization as the larger formats. It may still be a gating item for nascent FF mirrorless systems such as the one Sony is preparing for release. Note that the Sony RX-1 doesn't have a mechanical image stabilization system (it's electronic, and video-only). This gets to the basic point (and the philosophy that Panasonic pursues) that lens-based stabilization systems have greater capability - especially where it's really needed, for big telephoto lenses. This is not such a big issue in the smaller sensor formats, but becomes one in the larger formats.

Finally, there's the issue of profit stream. Adding stabilization to film-era lenses allowed the manufacturers to generate new sales from upgrades, just as autofocus lenses did. It still generates additional profits. Olympus saw in-camera stabilization as a means towards its overall design goal of small system size. IBIS came along as a marketing differentiator to which lens-based systems in their present form cannot respond. But considering that most purchasers of ILC systems own at most 2 lenses (average 1.5) - the ones that came with the camera kit - the cost advantages of an in-camera stabilization system are very small.

Ultimately, the main driver for moving stabilization to the body will be the need for small system size and expense, especially in the larger sensor formats lens size is the limiting factor - which is due in part to the inclusion of stabilization systems. All sensors today already move to shake off dust; it will be only a matter of time before the larger sensors cost-effectively move in 5 axes.