Paint on FDn 400/4.5 front element.

[tom_smith22]

<p>Not much, a very weak burst of spray paint that's probably not affecting image quality a great deal, but I'd like it off anyway. Lens cleaner doesn't work, and Im not sure about acetone, as I cant seem to find what the S.S.C. is actually made of, but Im guessing its far too powerful. Does anyone know of a safer way of taking these dots off, or am I stuck with a chickenpoxed lens?<br>

Cheers for reading.</p>

[paul_wheatland]

<p>give Frank Marshman at CameraWiz in Harrisonburg, VA a call. He's competent and knowledgable and has worked successfully on many unusual camera issues. He's highly recommended by some members of PHSNE here in New England.</p>

[fritz_carlsson1]

<p>Lens coatings are made by subliming thin layers of various metals onto the glass to which they bond. These are impervious to organic solvents which means that something that dissolves the paint, such as acetone or lacquer thinners, will work. They won't require much or any rubbing either, I expect.</p>

[w_t1]

<p>I'm not familiar with that particular lens, but i know - or at least I've read here - that the outer element on my 300 f4 EF lens is meant to be easily replaceable (by Canon). Maybe thats the case with your tele, I don't know.</p>

<p>I wouldn't worry about it if it doesn't effect image quality, it's probably worse when it's stopped down to 16 or 22, but most people are probably like me shooting tele at 5.6-8.</p>

<p>I always wonder how these things happen, I mean how distracted did the person have to be to get spray paint on a lens?</p>

<p>good luck<br>

Tom</p>

[tom_smith22]

<p>Thanks Fritz, Ill give it a go then. I do stop down to f/22 routinely so it is an issue, also I dont think canon are in the habit of replacing FD glass, at least not anymore. Thanks for the responses - Tom</p>

[feanolas1]

<p>Acetone is a no-brainer for lenses; the only risk you might incure is by using it on plastic parts: some plastics will disolve. That should not be a problem for your 400mm.<br>

Make sure you don't pour the acetone on the lens, as it would most probably seap into the lens and may then dissolve greases and/or plastics and deposit them on lenses and aperture blades.<br>

I use acetone first, but as this will often leave some traces when evaporating, I finish the cleaning with some distilled water: that will get rid of the acetone traces and should leave nothing behind.</p>

[tom_smith22]

<p>Acetone works a treat. Got rid of everything, even invisible dirt on the T90. Will definitely be using it a lot more but yeah, I was nervous about it seeping into the edges. It could wreck havoc on the internals. If you havent tried using acetone before, give it a shot.</p>