lens cleaning advice

[dexdog]

I recently acquired this lens. The glass itself is in very good shape, only a tiny bit of oil is visible on the aperature blades, and the pictures taken with it are great. However, as you can see from the attached pic, it was really grungy, and I felt weird attaching it to my fine Contax cameras. The first pic of the lens is lifted from the eBay auction, with the seller's watermark crudely scrubbed out. I knew that the lens was dirty when I bid on it, but given that these things do not appear very often, I decided to go for it, figuring that I could clean it up. Given the odor, part of the dirt was tobacco smoke residue. I tried using 70% isopropyl alcohol and Q-tips to clean it, but this combo didn't phase the grunge very much. Feeling brave, I used Ronsonol instead of the isopropyl. As you can see from the after pic, it cleaned up real nice, and the paint and nickel are fairly shiny.

My question is whether I need to do anything to further preserve the lens, or to counter-act the Ronsonol. Any ideas, suggestions or great thoughts?

dexdog

 

[RJBender]

I recently acquired this lens. The glass itself is in very good shape, only a tiny bit of oil is visible on the aperature blades, and the pictures taken with it are great. However, as you can see from the attached pic, it was really grungy, and I felt weird attaching it to my fine Contax cameras. The first pic of the lens is lifted from the eBay auction, with the seller's watermark crudely scrubbed out. I knew that the lens was dirty when I bid on it, but given that these things do not appear very often, I decided to go for it, figuring that I could clean it up. Given the odor, part of the dirt was tobacco smoke residue. I tried using 70% isopropyl alcohol and Q-tips to clean it, but this combo didn't phase the grunge very much. Feeling brave, I used Ronsonol instead of the isopropyl. As you can see from the after pic, it cleaned up real nice, and the paint and nickel are fairly shiny.

My question is whether I need to do anything to further preserve the lens, or to counter-act the Ronsonol. Any ideas, suggestions or great thoughts?

dexdog

Hi Dex,
Ronsonol or naptha won't harm the finish. You probably just need to buff the finish with a soft cloth and clean it again with the Ronsonol. You could test a tiny area with acetone or nail polish remover and see if it helps.
What are those characters along the back edge of the lens mount, Chinese?
R.J.

 

[FrankS]

Isopropyl alcohol and then Ronsonol are my cleaning solutions for camera gear. I wouldn't try acetone as that will surely eat into almost any finish other than bare metal.

 

[RJBender]

test

test

Isopropyl alcohol and then Ronsonol are my cleaning solutions for camera gear. I wouldn't try acetone as that will surely eat into almost any finish other than bare metal.

The best advice is to test any cleaning solvent in an inconspicuous area before using. I once used isopropyl alcohol to clean an Olympic Zenit EM assuming it was safe. Not so. The alcohol removed all the white lettering!

Acetone won’t harm some baked enamel finishes but it will ruin a plastic finish. There isn’t any plastic on the Sonnar.

Always use naptha or acetone in a well ventilated area, preferable with a fan providing cross-ventilation over your work area.

R.J.

 

[dexdog]

Thanks for the responses everyone. The reason that I asked is that the Ronsonol did not appear to harm the paint, but I wasn't sure about the longer term. I had read that Ronsonol evaporated completely leaving no residue, but had never used it on such a large scale. How about applying some car wax on the paint?

RJBender, yes the characters are Chinese, and are supposed to translate as "Made in Germany". Contax made some cameras and lenses specifically for the Chinese market in the early 1930s.

BTW, the lens smells a whole lot better after cleaning.

 

[back alley]

i just read somewhere that if you put the item (lens) in a baggie with a fabric softener sheet (bounce) and leave it for a day that all smells will be gone.

joe

 

[MacDaddy]

i just read somewhere that if you put the item (lens) in a baggie with a fabric softener sheet (bounce) and leave it for a day that all smells will be gone.

joe

...and it feels just like flannel when you rub it on your cheek! ;o)

 

[RJBender]

Thanks for the responses everyone. The reason that I asked is that the Ronsonol did not appear to harm the paint, but I wasn't sure about the longer term. I had read that Ronsonol evaporated completely leaving no residue, but had never used it on such a large scale. How about applying some car wax on the paint?

RJBender, yes the characters are Chinese, and are supposed to translate as "Made in Germany". Contax made some cameras and lenses specifically for the Chinese market in the early 1930s.

BTW, the lens smells a whole lot better after cleaning.

Hi Dex,
I wouldn't use car wax.

R.J.