Identify a Summicron 90 ltm

[S.H.]

For the summaron, the minimal focusing distance between the true ltm and the others is different, no?

 

[Erik van Straten]

For the summaron, the minimal focusing distance between the true ltm and the others is different, no?

The M-mount focuses to 0.7 m while the (true) screw mount focuses to 1 m.

The goggled Summaron focuses to 0.65 m.

I even have a goggled Summaron with a removable M-adapter. However, the lens cannot be used on a screw mount camera as there will be focusing error. The policy behind this I really do not understand.

Erik.