Minolta AF 28-75mm f/2.8 (D)

Set it beside a Tamron SP AF 28-75mm f/2.8 in Minolta mount and you will hunt for the seam. Inside, each carries 16 elements in 14 groups, and both focus down to 33 cm. That is because this lens is a derivative of Tamron's model A09, and your focusing hand can tell: Michael Hohner's lens table flags the focus direction as reversed, against the Minolta norm. The badge even costs you a part. Tamron fitted its version with a zoom lock switch, and this one goes without.

It went on sale in 2004, the year the Maxxum 7D reached shops, and on that camera's APS-C sensor it framed like a 42-112mm, an awkward range. On film the numbers mean what they say, with 28mm a genuine wide and 75mm a relaxed head-and-shoulders length. The D marks a distance encoder that feeds focus distance to ADI-capable bodies for flash metering. Its shelf life turned out short. Konica Minolta announced its exit from cameras in January 2006 and handed SLR service to Sony that March; Sony's own 28-75mm f/2.8 SAM didn't arrive until 2009.

Film also shows the weakness in full, because a 35mm frame takes in the outer field that the 7D cropped away, though Munger found the corners soft on APS-C too. Kurt Munger tested it on a full-frame Sony A900 and an APS-C A700. The center is good everywhere, though wide open it gives up a little contrast to spherical aberration, which f/4 cleans up. Out at the edges it struggles. At 28mm the corners needed f/8 to come good and peaked at f/11; at 75mm, stopping down mostly just removed the vignetting. Distortion piles on, with moderate, wavy barrel at 28mm and moderate to slightly heavy pincushion toward 75mm.

Keep the subject near the middle and it makes a very good people lens; Munger liked it for indoor events. Wide open, backgrounds fall away fairly smoothly toward 28mm and are merely fine by 75mm. Against Minolta's 28-70mm f/2.8 G it loses on edge sharpness across a full frame but focuses quicker and quieter. It also handled sun in or near the frame better than the G, though flare is only fair and the petal hood needs a hand's help at the wide end. Close focus is the real gap: 0.26x here against the G's 0.09x. At that ratio a 35mm frame covers about 14 by 9 cm, enough for the rings at a wedding.

Without that lock, the barrel wanders. Munger found the zoom loose enough to creep at 28mm; tilt the lens down and it runs out to 35-50mm. On the Tamron, the lock exists to keep the barrel from sliding out while the camera hangs from a strap, and it only engages at 28mm. On a tripod pointed down at a stream, check the zoom scale before you open the shutter. The focus ring also turns during autofocus, since the body drives the lens by screw, so keep fingertips clear.

Metering is the one job where this lens asks nothing of you. The aperture holds f/2.8 from 28mm to 75mm, so a reading taken in Zone Light Meter at full aperture stays valid wherever the zoom ends up, something a variable-aperture Maxxum zoom can't promise when shot wide open. Munger called it a less expensive alternative to the 28-70 G. Cross-shop the Tamron original too, since it carries the same 16-element layout plus the lock. Buy this one for the middle of the frame and stop down hard when the corners count, knowing that at 75mm stopping down mostly cures the vignetting rather than the corners.