best way of cleaning old LTM lenses (Canon 50/1.4 or similar)

[fer_fdi]

Hi all,

What would be the best and safest way to clean front and back glass surfaces of a 60s lens?

I have a Canon 50/1.4 with good glass in which I can see cleaning residue from the original owner.
One day I will send it for CLA (when I find a good local tech in Barcelona or Spain; any help welcome) but for now I'd like to clean it myself on the surface.

I don't like to clean old lenses because I'm worry of damaging the coatings, so what's the safest way?
I assume cleaning tissue + current cleaning lens fluid would be the best way...

Thank you

 

[Archlich]

Unlike contemporary Leicas, Canon's coatings are pretty hard so common sense should suffice.

 

[fer_fdi]

I have very little experience in cleaning lens glass since I'm one of those using a clear filter in front of it to keep it clean.
I don't like using them (B+W 007 MRC clear filters) but when I see what the filter collects, I don't want all that going to the front glass instead. And that's using a cap when not shooting!

This lens has no scratches or fungus or haze, just the normal dust particles inside.
But it has something in the glass that just moves around when trying to clean it, it doesn't go away with gentle cleaning, so I can't clean it properly.

Which method/product would be best?
Even Canon coating being hard as you say, it was made in the 60s so I guess special care is in order...

 

[Steve Bellayr]

Use a recommended cleaning agent and cloth. Some lenses have more delicate coating on the front of the lens than others with that said the front of the lens will get dirty if a filter is not used. Wet the cloth and wipe the lens, minimum pressure. Be aware that the front element does not affect the image much even with scratches or cleaning marks. It is the rear element that one must be very cautious cleaning as any damage to the rear element will affect the image. I recommend when changing lenses cap the rear element quickly. I have never had a problem using filters on the front of my lenses and do recommend their use. I have had people (most of whom should have known better) touch the front of my lens. I also have found that the front of my lenses get dirty or dusty or smudged so the filter is the object that takes the brunt of abuse.

 

[fer_fdi]

my main concern is the rear glass

that's why I look for the best option

 

[Fixcinater]

The 50/1.4, in my experience, is pretty tough. You could use lens cleaning fluid or Ronsonol (lighter fluid) or rubbing alcohol with no ill effects, as long as you pay attention to using a clean/fresh cloth or lens swab.

I bought one a while back with misplaced aperture blades, cleaned all the glass this way as I re-assembled after fixing the blades. No issues with coating damage.

 

[fer_fdi]

thank you.

What would be a good cleaning fluid? and a good lens cloth? in this case

I'm not brave enough to use ronsonol or normal alcohol on my 50/1.4! : )

 

[Jonathan]

Am with Fixcinator, I have this lens, if lighter fluid does not remove it, then time for a proper look by a pro.
Regards, Jonathan

 

[Fixcinater]

After I started using Ronsonol for cleaning internals, I stopped using other lens fluid. Only use Ronsonol if really have something that was wet that got on the lens somehow (day at the beach, at a party with those foam string sprayers, etc.

Anything else I forget about as it won't impact IQ or it will come off with a soft hair brush/blower.