Shac
Well-known
The rigid and the DR are optically the same, although the DR's might have been selected especially for use with the "goggles/specs"
Re. your question "Which version is best for classic M2 use?" - what lens(es) are you referring to? If the 35/2 - then the first version (without specs) is the same vintage as the M2 - but collectors keep the prices v. high. Tom A. highly recommends the 35/2.8 summaron instead. If the 50, then either the DR or the Rigid are the appropriate vintage.
David
Re. your question "Which version is best for classic M2 use?" - what lens(es) are you referring to? If the 35/2 - then the first version (without specs) is the same vintage as the M2 - but collectors keep the prices v. high. Tom A. highly recommends the 35/2.8 summaron instead. If the 50, then either the DR or the Rigid are the appropriate vintage.
David