Testnote:

For testing I used a ISO 12233 resolution chart as testing object with the camera mounted on tripod using the self-timer and mirror-lockup. I'm also commenting using the lens in day to day use and subjective feeling (like bokeh, flare resistant..etz)

FA 50/f1.4

The first lens I'm going to review is also a bit of a reference, namely the good 'old' FA 50/f1.4. It's not an expensive lens and on a FF camera it's a good all-rounder although I personally find the field of view (FOV) a bit narrow. I more like the FOV of a 35mm (see later). On a crop camera like the Ist*D I used for testing this lens becomes a great portrait-lens with a FOV comparable to 75mm.

Now about the performance:
Full open the lens is soft especially at the corners, but still usable for portaits. On a crop camera the vignettering  is not a great issue. From f2.0 on the lens becomes great, where it's still soft in the corners at f2 from f2.8 on it's tack sharp.
On the FF camera I'll find the difference greater between f2.0 and f2.8 then on the Ist*D.
Probably there will be a bigger difference when using this lens on the K20D or K7.
There is a bit of CA (I'll given it a 8 in my test notes). And contrast is very high together with the FA28-70/4 AL.
So overall I can recommend this lens.

The Ist*D max resolution is 2008 lines/h.