I had the Sigma 400/5.6 APO Macro in Pentax AF. Optically, it was a first-rate lens in every respect. The build quality was good also. I returned it within the 30-day return period because it didn't report the proper aperture when used on a Super Program, and I was afraid there would be further problems in the lens' compatibility down the road. But the photos it produced were as good as the Pentax F* 300/4.5, which is saying a lot, so overall the lens would have been a "keeper" except for my compatibility concerns.
But now Sigma reports they have discontinued production of that lens - because they sell many more of their 135-400 and other long zooms than the autofocus APO 400/5.6 Macro. The point of this is that Sigma's newer long zooms are optically crap, compared to the 400/5.6 APO Macro. Reviews and tests show they are soft at full aperture at the long end, and not much better stopped down. Really barely good enough for 4x6 inch prints, and useless for enlargements. So build quality and compatibility are issues, to be sure, but it seems modern buyers would prefer anything with the word "zoom" in it to an optically fine lens. I suggest Pentax start marketing "Zoom Primes." These lenses would actually be prime lenses, but with the word Zoom prominently printed in large letters on the side of the lens. This would satisfy the cranially challenged buyers who just want a good Zoom. Hey, maybe Pentax could even call their new line a CanoZoom. Sales would skyrocket, for sure. -- John Mustarde - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
