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Chippy3476
14-06-2015, 10:48 AM
Hi all,
Its been a while since I have posted on these forums, and seems like even longer since I have been out under the night sky with my scopes. Turns out having a second child really puts a stop to all your night time activities ;)

So to my question, how do you know when your primary mirror needs to be cleaned in a 8" newt? As I mentioned it has been sitting for a few months unused but stored with all dust covers in place. I took the main cover off to look at the mirror and it has a few specs of dust on it, i can only see the dust under torch light just kind of like a few specs here and there.
So will this effect my viewing at all? I really don't want to pull the mirror out to clean it, i have done ot on my smaller scope once before but that was only becouse I had to remove it anyway to place a donut in its centre for collimation.

Thanks everyone lets hear all your opinions.
Dan

kens
14-06-2015, 12:06 PM
Put down the torch and step away from the mirror, sir :)
A few specks of dust that you can only see by torchlight will not affect your viewing.

CJ
14-06-2015, 12:22 PM
:lol:
+1
Dropped a screwdriver on mine last time I cleaned it. :rolleyes: :screwy:

astroboof
14-06-2015, 12:34 PM
^ Yeas, me too, darn it! No real damage but.

Going by your description Dan it sounds quite light pollution, so not worry about it.

Oh I didn't mean light pollution as in lights, like lights on a street, erm..

glend
14-06-2015, 12:56 PM
Leave it alone for now. If you notice mold on it then clean it. Keep it in a dry place and use a mirror cover if you have one (most GSO scopes come with a plastic mirror cover these days). or you can use Astrozap end caps etc to close it off but still allow air through.
Plenty of guides to cleaning the mirror available online, but resist for now.

Chippy3476
14-06-2015, 03:30 PM
Thanks all,
i didn't think it was bad enough to clean yet but thought I would ask.
I am just to pedantic with my scopes :P even though they haven't been used in a few months I still somehow found the time once a week to wipe them down on the outside.
Thanks again everyone
Dan

Renato1
15-06-2015, 12:39 PM
I definitely agree with the others - don't do it.

Only do it when you look at it and say 'EEK - that needs doing'.

You should notice a fair bit more light scatter around planets and bright stars when the mirror is really dirty - and it takes a fair amount of dirt to do that.
Cheers,
Renato

Shiraz
25-06-2015, 07:33 AM
and even then, wait a couple of months.

SkyWatch
25-06-2015, 11:45 AM
... and it doesn't matter how clean it is, you will always see dust when you shine a torch on it. :eyepop: The moral of the story is: don't shine your torch on it! ;)