Originally posted by tabl10s FL not displayed
That is the expected behavior. Focal length is only available to the body with AF lenses. Non-AF lenses lack the data pin.
As for the maximum f/4 from your PKA adapter...Is the aperture ring locked into the "AE/32" position?* If it is only at the f/22 position the mount may erroneously identify as an A lens with f/4** max - f/22 range. Be sure too that BOTH tabs of the adapter are seated into position on aperture ring. There have been reports of defective PKA adapters always reporting as f/4 max. Let's hope yours is not one of them.
Link to Hin's Adaptal-2 PKA fix page
BTW...be easy with the scraping and only do it at the point indicated and only if you cannot get consistent detection as an "A" contact lens. That is all it fixes. The points in the illustration are countersunk screw heads, not contacts. For an explanation as to why this works, see:
LINK
Also, FWIW, my PKA adapter is just plain flaky off the "AE" setting when mated to any of my "A" contact bodies. As noted in a few of the comments in the link above, there is a benefit to engaging the "AE" before mounting the lens and simply leaving it there.
Steve
* The lock/release is a black tab at lower left on the adapter
** sometimes f/3.5...go figure