I finally got a couple of hours to take my new K10D and DA* 16-50 out into the field. I took some shots of Oak trees on the eastern edge of the Sacramento valley (along Ione Road south of Hwy 16). Here's a sample:
http://www.westerickson.net/misc/ValleyOak.jpg This started out as a DNG raw. I pulled it into Photoshop CS2 with pretty nominal settings, then used the channel mixer to convert to black and white. I did not apply any Photoshop sharpening. I thought that it was pretty impressive at first glance--sharp, clean, and with good dynamic range. The image in the link is a straightforward downsize with no subsequent sharpening. So I went pixel-peeping. Here are 100% crops of the lower left corner, center, and lower right corner: http://www.westerickson.net/misc/LeftCenterRight.jpg To me, the grass on the right is noticably "mushier" than the grass on the left. I've looked at a few other images and I see the same kind of behavior. I guess this is the dreaded "decentering" defect. Also, when I shoot near the long end of the zoom, the autofocus is very accurate. When I try to autofocus on distant objects at 16mm, the camera seems to immediately "give up" and default to about 10 feet (3 meters) or so. Autofocus seems ok for nearer objects. I'll have to mount this lens on my *ist-Ds to see if it's a K10D thing. Thoughts? --Mark -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
