"Dave" wrote:

Hi,

What is the best thing to use to clean a smudge (like a finger print) off a
lens? I know to use a protector filter but I have lens to clean that didn't
have one. I heard that some liquid type cleaners are not good for lens
coating. Is there a popular cleaning kit or cloth to use?

Thanks!


There is probably no more effective *and* gentle method than using
OptiClean, which is used in the most highly demanding applications
including cleaning front silvered mirrors used in astronomy. OptiClean
is a liquid that you spread over the front (or rear) element of the
lens, remembering to include one of the supplied tabs. You allow it to
set to a gel, then peel it off with the tab, bringing all the dirt and
grease with it. It cannot cause any damage because there is no
abrasion.

http://www.opticlean.com/

In the longer term, using a good quality multi-coated colourless UV
filter (not 'skylight', which has a colour cast) is the very best way
to protect your lens. There is a lot of nonsense talked about filters
degrading an image, but no-one can show you any reliable evidence that
they do, despite many people having tried to prove it - one way or the
other. The simple truth is, good filters don't degrade images.

Obviously it is best to avoid cheap filters, but any camera brand
filter, or anything from B+W, Heliopan, Sigma or Hoya's HMC range will
do the job very well. Personally, I find Hoya HMC filters difficult to
keep clean, as they smear easily, but I have had no such problems with
the B+W filters fitted to most of my lenses.

B+W filters are top quality German products that generally seem
expensive, however they are available at very reasonable prices from
several specialists selling on eBay.

Cleaning filters is very easy. Rinse the filter, then use warm water
and liquid detergent, rinse with deionised water, and dry with a soft
microfibre cloth. There's no need for specialised chemicals, but
OptiClean is always there to deal with any major dirt problem.