Telescope Eyepiece Maintenance

Q: “How does one maintain one’s eyepieces? I went up to the VIS last night and as I was packing up I started fretting about “Gee, should I put these away right now or should I bring them out so they can slowly adjust to the warmer humid air at home?” And then this morning I was looking at them to make sure there were no lashes or what-have-you and wondered “Should I be religiously cleaning these every time I take them out or are these one of those things where you   don’t _want_ to be fretting too much about every ‘hey, what’s that tiny shine?’ on the glass?

What is a good routine for maintaining one’s investment in (presumably) decent eyepieces?”


Christopher Erickson says:

I keep mine in individual “bolt” style cases and always make
sure they are in their cases before bringing them from a cold
environment to a warm environment to prevent condensation
from collecting on them.

And when needed a “Lens-Pen” is what I use to carefully clean

Be advised that over-cleaning optics can increase the risk of
damage to the optical coatings. Some optics have very hard
coatings (Televue, Pentax, etc.) and others (Brand-X, etc.)
often have much softer coatings.

Wayne Fukunaga says:

Condensation is a major problem going from the VIS to lower altitudes.  I prefer the “Bolt” type bottle cases with 2-gram desiccant packets added in them.  Keep those in a foam insulated eyepiece case unopened until the eyepieces reach room temp – a few hours.  The next rule is scratches on optical surfaces are very bad.  Scratches lower contrast and scatter light.  So, clean infrequently and sparingly  – dirt will block only single digit percentages of light.  Finger print oils and lashes should be removed with a weak detergent soaked q-tip (lens cleaning fluid or Windex).  Fungus loves to eat organic residue and etches glass.  Don’t use hard pressure when wiping.  Dry off with lens tissue.  Blow off or brush off any remaining dust.  Compressed cans of dust blower can stain optics if the liquid spits out, so keep the angle of the can vertical and a distance away and hold the eyepiece optical surface downwards so dust falls away.  Keep the desiccant fresh or recharged.  Fungus loves to eat the coatings on lenses.  Keeping the lenses in a dry atmosphere retards the fungus.  I like TeleVue products because they will replace scratched or fungus eaten elements at a fair cost.

I get my desiccant from:

Bolt Cases from:

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