What's the iron ball behind the Pentax lens?

Iron ball is the anti-shake technology behind Pentax lens, also called optical stabilization. The iron ball usually consists of a small spherical magnet and a set of coils, which are installed next to the optical elements of the lens. When the lens shakes or shakes, the coil will be activated by current to generate a magnetic field, which will make the iron ball subject to magnetic force. This magnetic force will make the iron ball move inside the lens, producing a reverse force to offset the jitter of the lens.

The function of the iron ball is to counteract the slight jitter of the camera or lens when shooting, thus providing a more stable image. It can help photographers use longer shutter speed in low light conditions and reduce the influence of blur and jitter. This is especially useful for taking hand-held photos, tracking moving objects or taking long-distance photos.

Besides iron balls, there are other anti-shake technologies, such as optical anti-shake and mechanical anti-shake. Each technology has its own characteristics and applicable scenarios. As a common anti-shake technology, iron ball has been widely used in many Pentax lenses, providing a more stable shooting effect and allowing photographers to take clearer and sharper photos.