Beginners Digital Photography Zone

Mirror Lens

By admin, September 10, 2010

Mirror Lens Mirror Lens
Can you clean a telescope lens and mirror with standard sunglasses cleaner and cloth?

My telescope needs a good dusting but I don't want to scratch the mirrors and lenses. I have some sunglasses cleaner and the cloth that comes with it. At first this seamed ideal, but then it dawned on me that perhaps a the moisture can get between the lenses and fog up upon use also the mirrors can scratch from the cloth.

You're going to get conflicting views on this probably. I make telescopes and I have cameras and microscopes and trained in laboratory work
Water is your first friend on a dirty telescope mirror. If you can take the mirror out put it under fast-running cold tap for a minute to get rid of most of the muck and then still under the tap and very very gently with very soft cotton wool with detergent on it wipe any remaining muck off.
Then pour de-ionised water over it and let it dry on it's side in a dust-free room.
If there is any dirt left on it you can remove it with very soft cotton wool very slightly dampened with water.
Do the same with the slightly damp cotton wool for lenses.
Zeiss, Leitz, hospital and research laboratories, all use that method.
Amateur photographers will scream blue murder at the damage it does.
Meanwhile the people who make the lenses know the truth.
Coatings nowadays are well able to stand being cleaned that way.
Phone your nearest pathology lab and ask how they do it...no glass cleaners used there apart from self-made wonderclean or ROR-1.
Super wonder clean no smears glass cleaner...as used in labs worldwide.
Works very well on the very very slightly damp cotton wool or a tissue folded so there are no tissue edges showing. Use each bit for ONE wipe then fold it over to get a fresh surface.
Then use a fresh piece. Tissues are cheap.
1 part of IPA...isopropyl alcohol..to 10 parts of de-ionised water.
Make screen wash for the car the same way. Get the IPA through eBay or a pharmacy.
Get de-ionised water from filling stations and supermarkets.
If you can see your face pretty well when you look at the mirror it won't need cleaning even if it looks a bit grimy.. If it's really mucky, OK clean it. But it has to be very mucky for that.

There is a very good cleaner called ROR-1 that NASA uses and my small bottle will last a lifetime. It does a wonderful job on camera lenses, telescopes, binoculars, etc but if they are really dirty clean them first and then use the ROR-1
http://www.ror.net/ . . . .
http://www.bluelakeproducts.com/ror.htm . . .. .
Sky and Telescope for a more intensive clean but most times a plain wipe off under the tap is all you need. I have 17 parabolic mirrors at home...10 home made and 9 are in telescopes.
Only two needed a really good scrub ...gentle cotton wool scrub...in a bowl of slightly warm water and detergent.
Bought very very cheaply....turned out a treat....bargain price for good mirrors that looked rubbish....hence the price.
http://www.skyandtelescope.com/howto/diy/3437191.html?page=3&c=y . . . . . .
Making mirrors...cheaper than some people lead you to believe.
http://stellafane.org/tm/atm/index.html . . .
See search term
http://www.google.com/search?q=ATM+telescope+mirror&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB:official&client=firefox-a . . . . .

Rokinon 500mm f6.3 Mirror Lens Test on Canon EOS 5D MkII