Dust inside Rokkor 58mm 1.2 (Images linked)

FM Forums \| Alternative Gear & Lenses \| Join Upload & Sell	Search Used
end

Archive 2008 · Dust inside Rokkor 58mm 1.2 (Images linked)

_enrico_
Offline
Upload & Sell: Off

p.1 #1 · Dust inside Rokkor 58mm 1.2 (Images linked)

Hi, I write here for first time, my name is Enrico, I hope someone can give me an advice.
I have acquired an old metal rokkor pf in really good condition except the fact that there is a lot of dust/haze inside. When I bought it I dont noticed that fact, but when at home I looked at the lens with a lamp on the other side...

I see a lot of dust... (that I have never seen in my other old lenses).

Here you can see images:
http://profile.imageshack.us/user/enrico_ -->ADD THE FINAL UNDERSCORE TO THE LINK... SORRY!
(I think that all the dust is in the internal surfaces in front and behind the blades)
The third image is from the rear lens, and is where the dust is more visible.

I have read the messages from cogitech and others rokkor users, and I read all the thread about the conversion and also i have found how to dismount the lens and I think I can do it.

But I think that the lens needs to be cleaned and I dont know how to clean the internal surface of the glass (which products to use for cleaning, what tools to use and HOW to do it!!), i dont want to ruin this lens that I have dreamed to use for months...

Thanks!!!

Dec 01, 2008 at 10:26 PM

Tariq Gibran
Offline
Dedicated FM
Upload & Sell: On

p.1 #2 · Dust inside Rokkor 58mm 1.2 (Images linked)

Well, I had the same thing and also thought the majority of the dust was on one of the front element surfaces. Turns out that most of it was on the last element of the rear group and some was on the last element in the front group(which you can easily get to once the rear group is removed and the aperture held open). Unscrew the rear group as one unit(hopefully it will not unscrew from the other elements as mine did) and simply blow(compressed air or blower) the dust off. I also use the condensation from my breath and a lens cloth, no special fluids. That's for the rear group. You will only be able to blow the dust off from the rear most front element through the aperture and I would not attempt to clean that further unless its obvious by that point there is a lot of dust there. If everything goes smoothly, no special tools are required for that. One tip which another member gave me which did help was to use a latex glove when unscrewing the rear group as its difficult to get a firm grasp otherwise. If that rear group did happen to separate, then you would need a spanner wrench to go further. You also need a spanner wrench for the front element but I certainly would not start there. Try the rear group first.

Dec 02, 2008 at 12:04 AM

Ed Sawyer
Offline
Upload & Sell: On

p.1 #3 · Dust inside Rokkor 58mm 1.2 (Images linked)

I use clean microfiber cloth and breath condensation for lens cleaning.

indeed it is probably in the middle of the lens, between the groups, which is the easiest place to clean these.

-Ed

Dec 02, 2008 at 03:14 AM

BKue
Offline
Upload & Sell: Off

p.1 #4 · Dust inside Rokkor 58mm 1.2 (Images linked)

This is what Zeiss recommends for cleaning microscopes:

http://www.zeiss.de/C1256D18002CC306/0/1205E8CBD68054EAC125701500404705/$file/46-0009_e.pdf

It works perfectly for most photographic lens surfaces (blowing / petroleum ether + isopropanol / breath condensation last). Do NOT use Q-Tips, but prepare the cotton swabs yourself!

Dec 02, 2008 at 07:33 PM

_enrico_
Offline
Upload & Sell: Off

p.1 #5 · Dust inside Rokkor 58mm 1.2 (Images linked)

Thanks to all for the useful informations!
I'll try first with blower/compressed air only.
Very interesting the document for cleaning microscopes!

Dec 04, 2008 at 11:32 PM

end
FM Forums \| Alternative Gear & Lenses \| Join Upload & Sell end