Originally posted by pathdoc I was merely trying to make the point that of all the Pentax lens series, the FA lenses had the best and most complete backward AND forward compatibility of the lot (at the present time).
Our reactions arose from the "most useful" tag in the headline.
As someone who appreciates focusing MF lenses,
even on modern digital bodies,
I would find the A series to be the most useful forward and backward compatible series.
In other words, for overall compatibility across the whole range of K-mount bodies,
I'd rather give up on AF in order to have full MF functionality.
Of course, that's a personal choice, but the A 50/1.2 makes it a very compelling one!
You've certainly opened up an interesting discussion.