9 out of 10 points and recommended12mm wide angle, constant F/4, good flare control, solid constructionNot fully compatible with camera flash. Minor occasional vignetting.
Manual warns that flash will create lens shadow especially with hood. I notice a slight vignetting at 12mm only occasionally with the hood but otherwise haven't noticed any light drop-off in the corners. Photos are sharp, especially at F/8 through F/16. Moderate CA at F/5.6, minor CA at F/8 limited to lines of very high contrast. Requires circular polarizer - hood has a portal to access filter. Manual focus ring is easy to find. Feels solid in the hand. Dropped 6 feet onto stone and still going strong. Great for landscapes at 12mm and group photos at 24mm. I use this and the 50-200 with my K100D. I don't miss the 25-49 range, but that's me. Highly recommended.reviewed August 1st, 2007 (purchased for $800)