Help disassembling a Rollei HFT 50mm f1.8?

[timichango]

Hiya! Good to meet y'all — first post here

I've been getting fairly deeply into older MF glass over the past few years (not counting time spent intermittently shooting film SLRs since the 90s), and have amassed a burgeoning collection of 60s/70s/80s lenses, including a few c/y and Rollei QBM Zeisses. Yummy.

One of my faves is the Rollei HFT 50mm f1.8 in QBM mount, even amidst the c/y planars, and I'm keen to get inside of my copy of the Rollei and clean up some mild hazing that seems to have accumulated on the rear group somewhere. I suspect the usual 'helicoid grease got hot and broke down a bit, and hazed an exposed element' scenario.

I've had very good luck pulling apart a few of the C/Y Zeiss lenses, in particular the 50mm f1.4, 85mm f1.4, and the 135mm f2.8, and all of those lenses benefit from the ability to pull out the front and rear group without dismantling the focus or aperture coupling whatsoever — it's possible to fully separate the optical groups from the mechanical assembly in those lenses.

Getting back to the QBM: I have a vague idea about how to get into the front (similar to the C/Y lenses, I reckon — spin off the outer cosmetic barrel thingy using friction, and then pull the front group out with a spanner or friction), but the back is more of a mystery. Can I just take a spanner to one of the two exposed retaining rings and yank out the group? Or is further disassembly of the lens required?

There seems to have been some info on the subject here: forum.mflenses.com/carl-zeiss-planar-or-voigtlander-color-ultron-50-1-8-repair-t49749.html — but the photos are missing, rendering those instructions somewhat useless.

If anyone can provide a definitive set of instructions (even better if they're visual) for getting into the rear-end of a late-model Singapore HFT QBM 50 f1.8, I'll be very super appreciative.

Bonus round: tell me that the QBM HFT Distagon 35mm f2.8 can be serviced in the same manner (whatever that manner happens to be), and I'll be overjoyed, as I've got one of those coming in the mail next week.

Cheers, and thanks in advance for your help!!

-T

[timichango]

note: url prefix stripped out of the forum thread link in the post above, as for some reason the link wasn't working properly, and all of the text after it was getting wrapped in the link for some reason — so you'll need to copy/past the url without the prefix into your browser to refer to the thread I'm talking about (which used to have disassembly photos).

-T

[RSalles]

HTH,

http://forum.mflenses.com/carl-zeiss-planar-1-8-50-qbm-reassembly-t67713.html

Cheers,

Renato

[timichango]

[RSalles]

The rest of the optics have to be removed by the front as it is positioned after the iris assembly, and IMO it will not pass trough it. Removal instruction as the infinity focus adjust that have to be carried out after that are in the thread I posted,

HTH,

Renato