Question Regarding CZJ Pancolar 2/50 and 1.8/50

[Oldhand]

Are these essentially the same lens in the manner of Takumar 2/55 and 1.8/55?
I have googled to no avail.
Thanks
OH

[Aanything]

I have both and, despite not having done a side by side comparison, I'd say they have some differences in rendering, with the f2 version showing some character in common with the earlier biotar.
Also, IIRC, the f1.8 version is a later model, not a more expensive alternative - as in the case of the takumars - so I suspect something in the design has changed between the two version.

BTW, i like the 2/50 very much.

[mo]

I prefer the 2/50 just for the styling,I don't know if they are the same as the 1.8 . I have both the pentax lens and did try them out, side by side for comparision...not much difference, but mine was not a clinical test

[iangreenhalgh1]

As Anything says, the 2/50 is closer in rendering to the Biotar. This is because it is less highly corrected. If you have the Biotar 2/58, Pancolar 2/50 and Pancolar 1.8/50 there is a clear development in the level of corrections noticeable. They are all roughly equal in sharpness but are progressively better corrected, most noticeably in spherical aberration and coma. This is why the Biotar has the swirly bokeh, the 2/50 has just a little swirl and in the 1.8/50 the swirl is gone - increasingly better correction of spherical aberration.

This increasing level of corrections is due to the advent of computers. The Biotar was designed in the 1930s, before electronic computing. The Pancolars are from the 50s and 60s respectively and considering that computing wasn't available until the late 1950s, I wouldn't be surprised if the 1.8/50 is a redesign of the 2/50 using the newly available computers to refine the level of corrections.

[Xpres]

I haven't used it in a long time, but I remember the 50/1.8 pancolar having some 'swirl' as one of its characteristics. Not as much as a Biotar, but there nonetheless.

[Oldhand]

Thanks everyone for the replies.
Google has finally been my friend and I have found some information based on some published schematics:

Pancolar 2/50:



http://www.pbase.com/kkawakami/image/108259869

Pancolar 1.8/50 Ist edition:



http://www.pbase.com/kkawakami/image/108259870

Pancolar 1.8/50 2nd edition:





http://www.pbase.com/kkawakami/image/108259872

This would seem to bear out the fact that the lenses are basically the same six element design, but tweaked from generation to generation.
Cheers
OH