[Docrwm]

Thanks, i was thinking the same, just wanted to hear others opinion. Of course, is posible to buy this lens paying some small amount of money every month and maybe someone can explain diference between FA and DA prime lenses? as i know FA is FF and you can use it for photo or film, DA is not FF and mentioned to use only for Photo. But maybe available some other diferencies between this type of lenses?

There are a variety of differences but the main ones are that the DA lenses are supposed to be tuned for digital use while the FA lenses were developed for film use. What does that mean? Coatings are more modern on the DA lenses and, as you indicated, the DAs are suppsed to be only Crop sensor image circle compatible. The problem is that folks have tried many of the DA lenses on full frame cameras and found they work just fine. Originally the designation DFA was for modern lenses that were still full frame compatible, however Pentax has mucked all those designations up and they are pretty arbitrary from what folks have been able to tell. A weird feature of some of the FA lenses is that they have the "Power Zoom" feature.

[knight6178]

and the most important question to me. As i understood, quality more or less is the same but which one is has faster and better focusing in low light?