 Essentially, this crops the center out of the image in-camera, but can be useful for metering and framing.Apertures from 2.8 to 11 are supported, though the largest apertures are not available at high zoom levels (3.7 at full zoom).Shutter speeds range from 60 s to 1/2000 s, although shutter speeds faster than 1/1000 s are not available at the widest apertures.