Aphid poo on my mirror

[osbourne one-nil]

I was using my telescope near a large Sycamore tree recently and I noticed today that it's got a few drops of honeydew (aphid poo) on the mirror. I didn't think there'd be any deposits from the tree as it was a frosty night, but it seems there were. 

Anyway, is it anything to worry about? If I should clean it, can I do it insitu with a bit of barely damp cotton wool and some isopropyl alcohol? I'd rather not take the mirror out as I think there's more risk of damaging it than leaving it well alone could possibly do.

Thanks

[Peter Drew]

If you do decide to clea the mirror I would suggest you use warm water contaiing a drop of washing up liquid. Point the telescope verically upwards and the curve of the mirror will form a reservoir for the water. Drag a cotton wool ball under it's own weight over the surface changing to a new one every pass until the goo is desolved. Once clean, repeat the process with distilled water. Finally tip off the water and allow the mirror to dry. Good luck. 

[osbourne one-nil]

Thanks - I've actually noticed Dave's included a section on cleaning the mirror. He suggests keeping it in place and using the bare minimum of water etc but otherwise as you suggest. I probably will give it a go as I have distilled water and isopropyl.

can never work out if I even need distilled water as our tap water is as soft as can be, but not going to risk it with a Zambutto!

[Stub Mandrel]

Honeydew is concentrated sugar solution, so it's very sticky and it can attack paint, so my advice would be to carefully clean in case it starts taking the coating off.

Now, what you really need now is a task-force of highly-trained parasitic wasps...

[osbourne one-nil]

Oh yes - or the Sycamore to be felled! 

As I say, I was surprised anything was being deposited as it was hovering around zero, but deposit they did!

[Stub Mandrel]

Perhaps the sugar acts as anti-freeze ;-)

[TheMightyKong]

This suggests insect droppings should not be left on mirrors as they attacking the coating, also a cleaning guide:

http://www.loptics.com/articles/mirrorcare/mirrorcare.html

Hope this helps.

[osbourne one-nil]

Thanks - I'll get it cleaned I think. I've never been afraid of doing it, and in the past have actually tended to use my fingertips, but I'll follow Dave's advice and washed it gently insitu. 

[DaveS]

As has been said, honeydew being basically a sucrose solution, isopropanol* won't dissolve it, you need water. I used to be able to buy a glass cleaning solution from the old A&B stores (Made by Tesnol, I think) that was in essence aqueous isopropanol. It got my car windscreen very clean until I had a load of honeydew on it, when it just made things worse, with the sucrose precipitating out. had to get a bucket of soapy water tot do the job.

* More correctly Propan-2-ol

[osbourne one-nil]

Ah yes, of course. I also have some liquid soap (liquid equivalent of pure soap flakes) so I'll do it with that. Thanks!

[Mr Spock]

If you do decide to clean the mirror I would suggest you use warm water contaiing a drop of washing up liquid. Point the telescope verically upwards and the curve of the mirror will form a reservoir for the water. Drag a cotton wool ball under it's own weight over the surface changing to a new one every pass until the goo is desolved. Once clean, repeat the process with distilled water. Finally tip off the water and allow the mirror to dry. Good luck.

Good advice.

[DaveS]

I would look for the cheapo "essentials" (Or equivalent) washing up liquid that has as little of anything else apart from the detergent, and use only just enough to do the job.

[osbourne one-nil]

That'll do.