Getting down and dirty with your mirror

[the lemming]

How dirty must a primary mirror get before you get into a cold sweat and think about cleaning it?

My telescope is less than a week old and has two trips to the great outdoors. This morning I've discovered dust, a couple of hairs and what I think are dried condensation spots. There are a couple of spots on the secondary as well.

My Hurricane Blower has shifted the dust and hair, but obviously will never shift the spots. I have also swung my 130p Telescope into an upside down position to allow gravity to shift as much dust as possible.

So, how dirty, grubby or mucky should a mirror get before you even think about getting the brillo pads out for a good buffing?

[Spec-Chum]

In a word, very.

I bet mine is much worse but I've not even contemplated cleaning it.

[Capricorn]

That is a decision that is up to you and ultimately only you.

You have been told "very" if you think it is very dirty then now what?

Stand it on the lawn and blast with a Karcher ?

First read the options for cleaning and decide after that.

[the lemming]

That is a decision that is up to you and ultimately only you.

You have been told "very" if you think it is very dirty then now what?

Stand it on the lawn and blast with a Karcher ?

First read the options for cleaning and decide after that.

Thank you for that insightful reply.

It helped a lot.

[cantab]

Sky and Telescope gave a memorable answer: If you're asking if your mirror needs cleaning, it doesn't!

[Carbon Brush]

One night you will be thinking that the view is not so good as it was earlier and wonder why.

A torch down the tube will show a really dewed up mirror.

If you still get something with a fogged up mirror, why bother about a bit of dust and a few stains?

[Bart]

One night you will be thinking that the view is not so good as it was earlier and wonder why.

A torch down the tube will show a really dewed up mirror.

If you still get something with a fogged up mirror, why bother about a bit of dust and a few stains?

Good answer, never thought of it that way.

Barry