Hi!
An Adaptall 2 mount lens works like an A-lens.
An adaptall (I) mount works like a K ogr M lens.
An Adaptall 2 mount lens works like an A lens -
- if it is an A (or later) lens
- if the Adaptall 2 mount is a Ka mount (and not an Adaptall 2 K mount)
As far as I know, the Adaptall (1) mounts predated the era of the Ka mount,
but there are both K and Ka versions of the Adaptall 2 mount out there.
It would make sense however I think that the coupling between the lens
and the mount is mechanical and then it is translated to electronic
signals to camera in case of Adaptall-2 mount... Though as usual I can
be rather far off base here...
I have Tamron 90/2.5 (49 mm filter thread) - the oldest version of it...
What a fine lens by the way... I have an Adaptall-2 mount for it. It
works like proper KA lens on my *istD...
YMMV of course.
Boris
