Century Tele-Athenar II 650mm min focus distance

[jmvic]

Can anyone help with the specs of this lens? Specifically what is the minimum focus distance? The reason I am asking is because the focus ring on my example does not seem to turn all the way to the end of the scale. The scale goes from infinity to 50ft and mine turns only to about 90 ft or around 200 degrees. Infinity focus is fine and the lens is sharp.
Any help would be appreciated.
Thanks

[Attila]

Welcome!

I have no clue about this lens.

[Kathmandu]

I do not own one of these-so I cannot help you with the MFD.



Heres a few paragraphs from McBroom's Camera Bluebook

Looks like a very interesting lens.

In 2000, Schneider Optics acquired Century Precision Optics, adding its over 50 years experience manufacturing superior attachments for film and video.

Cheers

[danfromm]

Ask Century.

If the 500/5.6 TA-II that I used to own and 300/5.6 TA I still have, these things are simple achromatic doublets with a flat piece of glass somewhere in the barrel. I have no idea what the flat piece of glass does, but the lenses are in no way telephoto. Long, yes, and with very long back focus, whence the tubes as long as focal length.

[jmvic]

Thanks everyone for the responses. I hadn't realised that there were no optics in the focus mechanism, but it looks like you are right. The plain glass at the rear is to prevent dust etc getting inside. It is also done by Nikon on their long tele lenses where the first element is in front of the aperture.