Hi Guoping, on 07 Mar 04 you wrote in pentax.list:
>this question bothered me a long time, and still couldn't find any answer. >Thanks. You can, but - you have no aperture priority as you cannot choose the aperture on the lens - the image circle is reduced at focal ranges below 22mm. Above 22mm the lens offers a full 35mm image circle Cheers, Heiko
