Zeiss Contax external mount RF lens focus adjustment

[sweat100]

I would like to know if there are any resources that I can read up or anyone who did adjustment on the focus of a 85mm Sonnar (external mount).

My lens front focus slightly, thus it is slightly shy of infinity when the lens is set at infinity focus.

 

[Highway 61]

If your Sonnar is a prewar or an immediate postwar Jena model, you can collimate it at infinity by adjusting the collimation shims seen on photo #3 on this Jupiter-9 page :

http://www3.telus.net/public/rpnchbck/Jupiter-9%20dismantle.html

A postwar Zeiss Opton or Carl Zeiss model will be built in a different way, yet you can collimate it as well..

 

[sweat100]

If your Sonnar is a prewar or an immediate postwar Jena model, you can collimate it at infinity by adjusting the collimation shims seen on photo #3 on this Jupiter-9 page :

http://www3.telus.net/public/rpnchbck/Jupiter-9%20dismantle.html

A postwar Zeiss Opton or Carl Zeiss model will be built in a different way, yet you can collimate it as well..

Mine is a post war Zeiss Opton Sonnar model. I am wondering if the steps to collimation remains about the same, i.e. access from the front. I can’t find much information online. Hoping someone will be able to shed some light.