Auto chinon 135 f/2.8, deep clean and relube.

roby02091987 · Joined: 15 Jun 2012 Posts: 9

Hi

I've recently acquired a very-used and not-in good condition auto chinon 135 f/2.8, with some problems. I'd like to clean it completely, since it seems a quite good lens.

The problems: Fungus (barely visibile and just on he externa side of the lens) on rear lens and second lens, focusing a bit stiff anche "crunchy".

Well, i've managed to disasseble the mechanical part of the lens.
In the lens I've found a piece of a dead leaf, with small pieces of it stucked in the old grease on the focusing helix, so I need to clean everything up and relube it.
http://i.imgur.com/FIe41.jpg
In this image you can see the focusing helix with all the little pieces of the dead leaf (the little brown dots).

So the first questions are:

1) How can I remove the grease and all the "bad things" that are on the focusing helix/screw ? What can I use? a cloth and ethilic alcohol? only a cloth? only alcohol? Soap? Something else?

2) I've got lithium/titanium grease and molybdenum disulphite grease at home. Which one is better for a lens?

Now, the hard part, cleaning the lenses.

I've read the thread in this section, and i think i'll use white wine vinegar for cleaning lenses (any other advices on this?), but the problem is:

3)how do I get them out of the barrel?

The rear lens is very easy to pull out: i just need to unscrew a metallic holder and it come out.
In this picture you can see the optical part of the lens from the side. It is upside down. The metallic black ring on the top is the ring that holds the rear lens. Unscrew it and the rear lens is free.
http://i.imgur.com/NWD4K.jpg

Here you can see all the fungus that are present on the (i think) second lens:
http://i.imgur.com/Y3923.jpg

And this is the front of the lens:
http://i.imgur.com/Vr1Sg.jpg

Now... how can i reach the second lens?

Thanks in advance for all the help

Ah, i forgot, this is the lens assembled:
http://www.blog.bkspicture.com/bilder/review_Auto_Chinon_135mm_f2_8/Auto_Chinon_135mm_f2_8_pic_1.JPG

inombrable · Joined: 20 Mar 2012 Posts: 545 Location: Salamanca, Mexico

Hi,

I use lithium based gresase to re lube my lenses, it is soft, but not buttery soft. (but it works)

And for the fungus use cold cream it works great.

To get to the second lens you will need to unscrew the nameplate and the retaining ring of the front element.

Good luck

roby02091987 · Joined: 15 Jun 2012 Posts: 9

Thanks a lot for your help Smile

.

By the way... do you know if this lens can be modded for infinty focus with glassless adapter on a nikon camera?

roby02091987 · Joined: 15 Jun 2012 Posts: 9

done, now the lens is free from fungus, relubed and focuses to infinity on nikon cameras... without the corrective lens, of course. Very Happy

It has some purple fringing wide open, that completely by away by f/4. Is it a normal behaviour?

Second question: anyone knows the optical formula of this lens? it seems to be 3 lenses in 3 groups... is it possible?