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#1 bleep

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Posted 12 October 2012 - 03:41 PM

Last night I added flocking to my xt8 which came out great. But I made the mistake of shining a flashlight on the primary and wow is it dusty! I used a can of air to blow off the top layer loose dust then just put it all back together mainly out of fear of me getting carried away and scratching it.

How often should the mirror be cleaned? I've only had my xt8 for a couple months.
I keep the caps on the scope and it is stored indoors but would keeping the primary end of the scope up help prevent dust from settling?
Any tips or tricks?

#2 csrlice12

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Posted 12 October 2012 - 03:47 PM

Dust is insideous, it'll get where you never thought it could get. You might try to put a shower cap on the mirror end of the scope to keep dust/insects frome entering that way. Also, make sure you keep a cap or eyepiece in the focuser along with the front cover.

A little dust on the mirror won't hurt, but too much and it will dim your views. If you have the mirror off, just rinse it off with a little DISTILLED water and let the water "run off". the mirror should dry spotlessly and put it back in the scope. Then you get all that collimation fun ahead of you....

#3 GOLGO13

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Posted 12 October 2012 - 03:54 PM

Dust is insideous, it'll get where you never thought it could get. You might try to put a shower cap on the mirror end of the scope to keep dust/insects frome entering that way. Also, make sure you keep a cap or eyepiece in the focuser along with the front cover.

A little dust on the mirror won't hurt, but too much and it will dim your views. If you have the mirror off, just rinse it off with a little DISTILLED water and let the water "run off". the mirror should dry spotlessly and put it back in the scope. Then you get all that collimation fun ahead of you....


Agree with just running distilled water over it for now. If it's really bad...try to do more research on cleaning mirrors. But just running the water over it won't hurt.

#4 NeilMac

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Posted 12 October 2012 - 04:08 PM

I would suggest distilled water, city water can be corrosive depending on the contents.

#5 csrlice12

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Posted 12 October 2012 - 04:27 PM

About 25 years ago, the Jennifer Beale method of water pouring was the preferred method.

#6 sopticals

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Posted 12 October 2012 - 04:34 PM

When you "park" your scope, do so in the horizontal to avoid dust accumulating on the mirror. One of the quickest ways to gather dust is to park the OTA vertically mirror at bottom.I would NOT suggest vertical parking with primary up, in case it gets wrecked by falling out of its cell.

Stephen.

#7 AlBoning

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Posted 12 October 2012 - 04:41 PM

http://www.arksky.org/asoclean.htm

#8 csrlice12

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Posted 12 October 2012 - 04:42 PM

...but a new mirror, is a clean mirror. :lol:

#9 MitchAlsup

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Posted 12 October 2012 - 05:45 PM

How often should the mirror be cleaned?


A mirror should only be cleaned when you absolutely cannot stand to put it off any longer. Generally 2+ years.

#10 Ed D

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Posted 12 October 2012 - 07:42 PM

The room where I store my Dob has a ceiling fan that gets used frequently. I had a huge problem with dust and dog fur getting into the scope. The stuff was being blown in through the gaps between the primary cell and tube. A simple 99-cent shower cap stopped the problem. Now it's at least 2 or more years between cleanings. I use the factory objective and focuser covers.

The mirror should only be cleaned when the view is noticeably degraded. Also, shining a light on the primary is the worst way to check it, as it will make it look like you have a truck load of funk on it.

Ed D

#11 NeuWerld

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Posted 12 October 2012 - 11:10 PM

http://www.arksky.org/asoclean.htm


Funny that I see this thread now as I literally JUST finished making a batch of ASO cleaner immediately before logging on to my PC 5 minutes ago. Wow, just wow...have only tested it on my bedroom mirror cause I didn't want to just jump into my optics without testing it first and there is literally NO streaking at all and the mirror is crystal clear. The only tough part was tracking down Kodak Photo-Flo 200, had to have a local camera shop special order it for me (thanks a lot digital photography age!) and could only get the 16oz bottle...which using 2 drops per batch of ASO should last me roughly 4 or 5 lifetimes. Super easy to mix and amazingly great results, I'll +1 this reccomendation.

Edit: Forgot to mention that if you find yourself feeling compelled to use compressed air, pick up a Giotto's Rocket Air Blower instead. They're relatively cheap, have an incredibly strong gust of air, use a 2 valve system so dust and particles aren't sucked back up into the blower, and don't have the chance to spray your finely coated optics with propellants that compressed air uses.

#12 TexasRed

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Posted 14 October 2012 - 12:50 AM

If you've only had your dob for a couple of months, it probably does not need cleaning. Any time you shine a light down the tube, all mirrors will look like they need cleaning, even if they were just cleaned yesterday. It takes a lot more dust than you think to dim your views by any noticable amount.

#13 Tim2723

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Posted 14 October 2012 - 05:10 AM

Red makes a good point. Never shine a flashlight down the tube. What you see will disturb your peace of mind. Conventional wisdom is to clean mirrors as infrequently as possible since the risks can far outweigh the benefits.

#14 JLovell

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Posted 14 October 2012 - 06:09 AM

I put a shower cap on BOTH ends of mine. The factory tube cap doesn't really seal all THAT well, and when I bought the shower cap, it was a two pack, so.... I've had mine for 3 years now, and it is almost as clean as it was new.

#15 csrlice12

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Posted 14 October 2012 - 09:00 AM

I believe you mentioned you just flocked the tube--did the mirror get dirty from where you cut/installed the flocking material, or did this happen afterwards (stuff flaking off the flocking material)? If it's the latter, that should not be happening.

#16 bleep

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Posted 14 October 2012 - 09:42 AM

I noticed the dust when I took the primary off before flocking. I used protostar flocking paper and I've read that's its some good stuff.

#17 FlorinAndrei

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Posted 14 October 2012 - 02:40 PM

But I made the mistake of shining a flashlight on the primary and wow is it dusty!


Big mistake, indeed. ;)

How often should the mirror be cleaned?


Once a year or even more rarely. Dust that looks awful under a flashlight, has surprisingly little effect on the image.

If you live in a humid climate with lots of ocean salt in the air, or industrial pollutants, clean up the mirror more often. This is to prevent salts and pollutants from tarnishing the mirror.

If you live in a dry climate, with clean air, no salts or pollutants, not much dew, and you stay away from dust, you could clean it almost never.

After a year or so, when you do clean it up for the first time, this is how it's done:

http://www.youtube.c...h?v=9Y8xFnXFVGQ

#18 orion61

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Posted 14 October 2012 - 04:48 PM

You need to get into the hobby of NOT CLEANING YOUR MIRROR, I went down the road of over cleaning, it ended up with a scratched mirror, and worse yet a chip on my Celestron SP 102's lens. I was able to move the silver spacers and cover the chip but it did cure me of the cleaning bug.
Getting into the habit of leveling the scope whenever youe eye isn't there for over 20 min. Also don't leave it outside in your secure back yard/campsite. keep it covered and DON'T USE A FLASHLIGHT, it will make a new mirror look bad.

#19 michael hester

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Posted 14 October 2012 - 06:06 PM

You can clean your mirror by turning off the flashlight :p






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