Pentax HD DA 28-45mm f/4.5 ED AW SR Aperture Series @ 28mm: Pescadero Creek Upstream Blue (645Z)
Get Pentax 645 and Pentax 28-45mm f/4.5 at B&H Photo.
The Pentax HD DA 28-45mm f/4.5 ED AW SR is equivalent to a 23-36mm lens on a full frame DSLR (long frame dimension).
At about $4697 it’s a substantial investment, but it does cover a very useful range. The main thing is that it is huge and heavy, much more so than its 35mm f/3.5 sibling.
This outdoor far-field scene explores the consistency of sharpness across the field and near to far at the 28mm zoom setting. There is a lot to learn from this scene as to the lens behavior.
Pentax HD DA 28-45mm f/4.5 ED AW SR Aperture Series: Pescadero Creek Upstream Blue
Includes image sizes up to 25 MP , along with very large crops, at f/4.5, f/5.6, f/8, f/11, f/16 plus RawDigger exposure info.

PENTAX 645Z + HD PENTAX-DA 645 28-45mm F4.5ED AW SR @ 28mm
[low-res image for bot]