Cleaning eyepieces is an easy and essential step to getting the most out of your scope. Eyepieces, if dirty, will provide downright ugly images. While care should be exercised to prevent scratching the coatings, the eyepieces can be cleaned for decades without problems. Most eye
pieces don't come with cleaning instructions but take heart! An eyepiece is basically the same as a quality camera lens, the same cleaning techniques can be used. I have camera lenses and
eyepieces that have received regular cleanings for nearly thirty years with great results.
Important Side Note here: I don't know the effects of these cleaning techniques on telescope mirrors or fluorite elements. Follow your manufacturer's directions for cleaning those products.
Eyepieces need more frequent cleaning than objectives because they see more People interaction and so collect fingerprints, eyelash grease, etc. It is still best to not clean an optics that are not dirty, as then there is no chance of causing any scratches. But the oils in fingerprints and eyelash grease contain acids, and all sorts of other "Stuff" can collect on the eyepieces during normal use, and it is necessary to get these materials off your eyepiece to provide the best possible views and to prevent damage to the coatings. I had a child touch my eyepiece with a used sucker Oh yeah! I was loving that !!!
I have an eyepiece cleaning kit that is very portable. It is comprised of an anti-static brush, a microfiber cloth,Q-Tips, and a small bottle of alcohol (91% or better). We want alcohol and water as the only ingredients.The alcohol is stored in a small bottle.
To start cleaning, make sure the eyepiece is free of dirt, dust and grit. (I would not go this far Look at photo!) I examine the eyepiece under a good light I carefully blow on the surface, then lightly brush the surface with the anti-static brush. Once the surface of the eyepiece is free of dust and grit, examine it for smears or streaks of oil. If there are any, lightly moisten a Q-Tip with alcohol. Starting from the center, lightly rub the Q-Tip in a circular motion from the center out, until you are at the edge of the eyepiece element. Don't use a lot of alcohol, as you don't want the alcohol to pool and run under the edge of the eyepiece lens.Once you have cleaned the lens on the eyepiece, use the dry end of the Q-Tip and mop up the alcohol on the surface. Discard this used Q-Tip. It is important to mop up the excess alcohol as if it fully evaporates, it will redeposit the oils and grease back on the lens. You can safely perform the alcohol cleaning again with a fresh Q-Tip if necessary. feel free to change out Q tips regularly
Next up, I will reexamine the eyepiece again under a bright light. Often it is impossible to get all the grease and oil off the lens without irrigating the eyepiece with alcohol. This is where the microfiber cloth comes in. If necessary, I gently polish the surface of the eyepiece with the microfiber cloth, after again examining for dust, which traps any residual oil and grease within the cloth. Once you are done cleaning, recap your eyepieces
Remember, the only thing that is going to scratch your eyepieces is dust and grit. Remove that first. Keep your anti-static brush, Q-Tips, and cleaning cloth or tissues in a dust free container so that they can't cause any scratches. Use gentle pressure with the Q-Tips and cloth. Rubbing harder won't pick up more grease. i hope this helps as You well know by Now My scope does a lot of public duty and hence needs a lot of eyepiece cleanings Until next week ...
Clear skies and great seeing too!