Pentax D Fa 70-210Mm F4.0 Ed Sdm Wr Lens

Focus-Range Limiter

This lens features a focus range limiter, which helps you minimize AF operation time by limiting the operational range of the focus mechanism. By selecting one of the two operational sub-ranges divided at a focusing distance of two meters (0.95 meters to 2.0 meters; 2.0 meters to infinity), you can cut AF operation time down to nearly one-third of full-range operation.

Operating the focusing range limiter:

Slide the focus range limiter switch to the LIMIT position, and the focus range is automatically set to one of two sub-ranges (0.95 meters to 2.0 meters, or 2.0 meters to infinity) according to the position of the focus-element group at the moment.

For instance, if you activate the focus range limiter when the lens’s focus ring scale indicates a focusing distance of five meters, the focus range limiter automatically selects the sub-range of 2.0 meters to infinity. When the focus ring scale indicates one meter, it selects the sub-range of 0.95 meters to 2.0 meters.

Applications:

Sub-range of 2.0 meters to infinity: When you want to focus on images such as an airplane or automobile positioned at a distance beyond a wire fence, you can select this sub-range to ensure that the camera does not focus on the fence

Sub-range of 0.95 meters to 2.0 meters: When you want to focus on the subject a short distance away, such as a flower, you can select this sub-range to keep the camera from focusing on distant objects in the background, such as a building.