I just got a used (seriously mint) Nikkor 28mm F/4 PC MF lens. But I realize already that I have no idea how to use it. So I'm looking for a manual for this lens. I did the search but was not capable of locating it. Also, I've programmed the D700 for this lens, but no matter what I do the D700 refuses to change from f/4 in Aperture mode. I have the lens set to F/22, but camera set at f/4 as highest aperture. Confused as there are no aperture blades either.... What am I missing & doing wrong?