Originally posted by D1N0 Must be the first version then with 5 elements. Lettering on the front ring is also ore archaic. According to this site:
Takumarology - Takumar Field Guide v1 has a serial number between: 580xxx and 1891xxx.
Thank you for reinforcing my lean towards V1. Looking at the reflection of my face on the rearmost element, it could be flat.....or it could be my face.....I avoid looking at my reflection much.
I do agree with the angry photographers opinion of the build quality, this lens may be old and tatty but the inner workings seem to reflect superb precision parts.
Time for a look through the site you provided a link for.