Does this mirror need to be cleaned?

[steveb1977]

I'm looking for opinions if people think the mirror pictured here is in such a state that it needs to be cleaned. I aware that cleaning a mirror should be a last resort but Im just not aware what the condition needs to be before it would have to be done. Thanks in advance.

[ronin]

Difficult to make out but it almost looks as if a resilver could be on the cards.

Is that corrosion on the "far" side ?

Not cleaning is one view but if anything is chewing it's way into the coating then cleaning earlier is a lot less expensive.

[knobby]

Its a very subjective opinion but from the photo you've uploaded I'd say yes. There's very poor reflections of the window frame.

but they do have to be pretty filthy to need cleaning, as you've already got it out I'd go for it, just you tube the tutorials and take your time

[Bart]

I would have thought that was ok, but as Knobby has said, you've done the hard part, taking it out, so I'd go ahead and clean it now, is that a 12" or something? Looks big enough, probably a bit of a handful so be careful. Good luck.

Barry

[steveb1977]

Yeah, myfeeling was that it would need to be cleaned so think I will go ahead with that while it is out. The mirror is 8.75". I think it is just the angle the light is hitting it on the far side that gives it that blue colour that looks like it might be corrosion.

I have already had a quick look at how to clean them and have read that the final rinse should be with distilled or deionized water. Is there any differce between these?

[cotterless45]

Yep, use distilled or you'll get crud. We got ours off the web,

Nick.

[moriniboy]

I'm looking at the photo on my phone so its not the best resolution. If that was my primiary i would clean it, you would then be in a better position to see if re coating is required.

[Cath]

I couldn't stop myself cleaning that mirror, the urge would just be too great

[Peter Drew]

Hold the mirror up to the light and look at the back of it, if you can see through it in patches then no amount of cleaning will make much difference, it will need recoating.

[steveb1977]

Thanks for all the advce. Have just tried holing it up to a light and can actually see pin holes of light coming through it in some parts. I'm guessing that this means a re-coating would be needed.

[nightfisher]

A few pin holes are okay for the time being

[steveb1977]

I guess I have nothing to loose with going for the clean then. Can anyone advise on distilled or deionized water. Some of the guides I have seen say one, some say the other for rinsing. Is there any difference?

[Naemeth]

I guess I have nothing to loose with going for the clean then. Can anyone advise on distilled or deionized water. Some of the guides I have seen say one, some say the other for rinsing. Is there any difference?

"Deionised water, also known as demineralized water, is water that has had its mineral ions removed, such as cations like sodium, calcium, iron, and copper, and anions such as chloride and sulfate."

"Distilled water is water that has many of its impurities removed through distillation. Distillation involves boiling the water and then condensing the steam into a clean container."

http://en.wikipedia.org/wiki/Purified_water

HTH

[steveb1977]

Thanks for that. Had never heard of deionised water so wasn't sure if it was ok to use. I know where I can get hold of that though. Will post a few pics of the results tomorrow, as long as I'm not crying over them!

[Naemeth]

I actually think distilled might be a better idea. Just a thought .

[NGC 1502]

You can use reverse osmosis water for the final rinse (it's used in aquariums).

Find a local aquarium shop that sells it, and take along some clean containers.

Regards, Ed.

[steveb1977]

You can use reverse osmosis water for the final rinse (it's used in aquariums).

Find a local aquarium shop that sells it, and take along some clean containers.

Regards, Ed.

Thanks Ed, will add the to my fact finding for tonight.

[russ.will]

I just used de-ionised battery top-up water for cleaning mine and then chased the drips off with a bulb type air blower - Worked a treat.

Russell

[DaveS]

You can sometimes get purified water from good pharmacists.

[steveb1977]

Job done and I'm happy (and relieved!) with the results.

A rinse with tap water followed by soaking in soapy water for 10/15 minutes. Minimal use of cotton wool on the worst area followed by a rinse with tap then deionised water. Just the soaking in the soapy water did most of the cleaning. Safely back in the scope and ready to go. Scope could probably do with a touch up as well!

Thanks for all the advice and opinions.

[NGC 1502]

Result

Looks like a great no-nonsense scope.......

Regards, Ed.

[steveb1977]

Cheers Ed,

Built it myself so its certainly no-nonsence.

The most technical thing on it, and the only thing bought off the shelf is the focuser. Pretty much all just plywood and screws.

[Moonshane]

great job. cleaning mirrors is pretty simple really, you just need kid gloves and you did well. I like the scope - very unique. I bet it's solid too.

I generally clean mirrors only before selling (not that I sell much these days) as people like a shiny mirror but I doubt' you'll see any difference, unless you observe the Emperor's new clothes

[steveb1977]

Yes, just need to go very gentle with it. Best advice I saw was that if a mark doesn't come off in the first atempt, leave it there.

[Mr Fiery Jack]

My scope is 8 years old and has never been cleaned, looks remarkably clean, amazing really, unless I point a touch at it.