dusting the secondary

[Jimtheslim]

I know a lot of people will say a bit of dust on the secondary will make no difference, however I am the kind of person who cannot let it lie. I'm not looking to take it off and give it a clean, just try and get rid of some dust. The method I am considering is a long straw to blow air at the secondary and a hoover pipe inside the tube, but being careful not to touch or knock anything. Would this be legit, or might I run into problems?

[Moonshane]

How are you blowing the air out? If with your mouth then you are very likely to spit on the mirror causing even more issues. I'd not bother.

[Peter Drew]

I would say leave well alone, only look at it at night when the dust won't show! 

[Jimtheslim]

49 minutes ago, Moonshane said:

How are you blowing the air out? If with your mouth then you are very likely to spit on the mirror causing even more issues. I'd not bother.

I was going to use my tempestuous lungs to blow through the straw, hoping I don't dribble. Maybe I will take the advice above and only look at night. I am just a bit concerned that I have only had the scope over a month and out observing half a dozen times. Checking my collimation it looks a lot more dusty than I would have hoped (yes I am keeping all the caps on.

[DarrenH]

Can of compressed air would be better then blowing on it.

[Stu]

4 minutes ago, DarrenH said:

Can of compressed air would be better then blowing on it.

Compressed air is generally not recommended, I believe it potentially has contaminants in it, can't quite recall the reason. A good old jet puffer is normally safest.

[DarrenH]

Ah OK. Same goes for a small air compressor then?

[Stu]

34 minutes ago, DarrenH said:

Ah OK. Same goes for a small air compressor then?

I think a compressor is actually worse, because of the risk of small particles or dirt from the internals of the machine. Best be safe, a little dust is preferable to damage or scratches.

[Jimtheslim]

I had read bad things about cans of compressed air. Whilst I wouldn't think twice about using one to blast out all the Mcvity crumbs in my keyboard, I wouldn't take aim at a precision mirror. I actually have a cheap plastic, accordion style airbed foot pump that I use on my eyepieces (with the nozzle on it delivers a great little blast of air), however the nozzle has been known to shoot off so I'm not putting that anywhere near it either

[jetstream]

You know, as fussy as I am about cleaning optics I don't use air of any kind to blow the fine "sand" (dust) off of mirrors. If cleaning I always use a dishsoap (few drops)/water solution to lube those fine particles...... then proceed to the next step.

Eyepiece/objective coatings might be harder than mirror coatings, and I personally use a Giottos Rocket blower for these as the first step in cleaning them.

Cleaning optics is fine as long as you learn to do it properly.

Before you clean anything I would do a LOT of research.IMHO.

[Jimtheslim]

I did a heck of a lot before cleaning my refractor and eyepieces and have seen quite a few videos on cleaning primaries (did I mention I can't help fiddling with things?!). I think I will stick to only looking at the thing at night, if I look at the dust on it during the day I won't be able to leave it alone

[Tyson M]

Rocket blower. I have two and love em. For my telescopes and glasses 

[t0nedude]

Basically what Tyson M said, I have one and it's great:

https://www.amazon.co.uk/gp/product/B00017LSPI/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

Tony.

[Dave In Vermont]

I'd shop around before buying the one linked above. £16.98 is a very high price!

I use one like it, and a very fine optical-brush which I also blow-off with a blower first. That takes care of any dusty particles on my mirrors.

Hope it helps -

Dave

[Peter Drew]

I refer you (and anyone else) back to my earlier post.