Is it ok to leave eyelash marks on the eyepiece lens?

[pat]

Does leaving eyelash or fingerprint marks on the lens damage the coatings? It seems like when I'm out, I later see a smudge on the lens. I've heard that it is better not to clean them that often. Pat

[Pete Presland]

it would certainly be better not to leave any marks on any of your equipment whether its a eyepiece or mirror.as for cleaning its recommended not to,depends how bad they are.

[James]

I don't stress about dust but I do tend to get rid of fingerprints and anything organic like pollen etc. Eyepiece coatings are generally quite strong and will cope fine with a gentle clean

[Moonshane]

I work on the basis of clean only when necessary. like James I only tend to clean when I can see any dust at the scope (usually the moon is the revealer of this), or when it's a greasy type mark. I think coatings are made of metal so there's no need to worry about cleaning them carefully but easy does it as with all optics.

[brantuk]

A little puff of air on the lens ought to remove eyelashes using one of those rubber "air puff thingy's" found in camera lens cleaning kits.

Byt greasy finger prints need to go - see above.

[Macavity]

Be afraid... be very afraid: Demodex - Wikipedia, the free encyclopedia (Eyelash Mites!)

Another (general) reason why I tend to prefer longer eye relief eyepieces. Also (convincingly) cleaning the tiny eye-lens of some eyepiece types always kinda worries me...

[chiltonstar]

The marks will be grease plus body fluids, including salt which may well attack a fluoride anti-reflection coating given time! I would clean occasionally with a spectacle cloth, or something very soft moistened with a commercial lens cleaning agent to avoid any risk.

Chris

[John]

I only use the Baader Optical Wonder fluid and micro fibre cloth on my eyepiece lenses now after an unfortunate experience with a so-called "optical cloth" and a nice TAL 25mm plossl

Like James, I'm not bothered by a few dust particles but I do clean the eye lens if I get eyelash marks on there. Eyepieces with more generous eye relief help avoid this, as Macavity says.

I have heard of astronomers trimming their eye lashes on their observing but thats going too far I reckon

[brantuk]

I don't trim mine - I just take them off at the same time as removing the nail extensions and frock lol

[John]

I don't trim mine - I just take them off at the same time as removing the nail extensions and frock lol