[Stephane]

Hi all,

While collimating my Newtonian mirrors, I noticed some strange stains on my coma corrector. It looks like dried up water droplets (I once got hit by a little rain) but I can’t say for sure. What a shame. I’ve only had this coma corrector a couple of months and it cost me $589, so I’d like to have it looking a little cleaner. Flats seem to eliminate any artefacts as I’ve never noticed this until today.

Any advice on whether I should clean it or just leave it? If I clean it, I’m a little worried about damaging and smearing the anti reflection coating.

Many thanks,
Stéphane