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stephend
30-03-2009, 06:11 PM
Have just moved 5 doors down the street and further into Newcastle's industrial glare. Only celestial object I can see most of the time apart from sun is the moon. So I'm going to have to become a selenologist for a while, otherwise known as a loonie I guess. Moon looks fantastic through a 10" scope but trouble is the glare, of course, which I'm sure is very bad for eyesight.

Point of post, can anyone tell me about moon filters?

I'm sure there are ones that don't work, and ones that spoil the view, etc. etc., for the unwary to buy.

Scope takes the larger size eyepieces, 2" I guess, with an adapter for the smaller ones.

Thanks muchly

Blue Skies
30-03-2009, 07:21 PM
There are several options. I'd recommend either a 0.9 Neutral Density filter or a variable polarising filter. Both work a treat to dim brightness without losing colour or detail. But if you get some coloured filters I've found orange and blue bring out some nice detail too.

PCH
30-03-2009, 08:20 PM
For me, just the cheapies from Bintel have worked fine. All they do is dim the view so you don't get blinded, but other than that the clarity appears unaffected - which is what you'd want I guess.

Cheers,
:D

sheeny
30-03-2009, 08:32 PM
I think mine is a 30% neutral density moon filter, which is fine for an 8" scope. It's probably Ok for a 10" too. A pair of polarising filters will give you an adjustable moon filter by varying the relaive angle between the two polaring filters.

Al.

stephend
30-03-2009, 11:13 PM
I like the idea of adjustable polarising filters. Who do you recommend buying from?

TJD
30-03-2009, 11:14 PM
:thumbsup:why not make an apercher mask it cheap (realy cheap)work for my 12" and itmake the scope more astheticaly pleazing like a apo refracter i guess
how to make one google but mine took 2 mins easy as costs $0.30 cheap easy what more could you want even correct light all it is is like your dust cap but with a hole in it and made out of paper:thumbsup:i com up with the best options:D :bowdown:

cheers
trevor

Blue Skies
30-03-2009, 11:59 PM
Anyone who sells Meade products, I like theirs best. The Celestron ones aren't as good imo, but maybe someone else has something to say about them.

bluescope
31-03-2009, 03:15 PM
You could just leave your dust cover on with the cap removed from the hole .... assuming your dust cover has a hole like SkyWatcher's do.
Whoops just noticed you have a Meade !

:thumbsup:

DENMONKEY
31-03-2009, 08:12 PM
I feel your pain mate. I'm too close to com steel and regularly curse them on a nice night when i drag the scope out into the backyard.

If you stumble on or know of any nice relatively dark/local sites let me know.

Might even shout you a 6 pack for the info, so long as you don't mind sharing it at said site :)

TJD
31-03-2009, 11:27 PM
dont be some mean to him just because he dosnt have the best scope ever made:P

xnomad
01-04-2009, 11:06 AM
With aperture masks are they only of use with large reflectors or could I make one for a 5" Mak Cas? I'm assuming rather than making an off axis hole you would just create a donut like mask?

I might have a go at this for moon viewing as I was blinded by the glare last time. I'd rather not get a filter as I'd have to get a 2" and a 1.25". Unless there is a way of putting a filter on the diagonal?

rmcpb
01-04-2009, 12:48 PM
Can't remember the formula but resoultion is directly proportional to aperture. If you reduce your aperture you reduce your resolution so, for that reason, an aperture mask may not be the best way to go. A good 1.25" filter will work for most as the use of 2" lenses is not really necessary for lunar observation.

erick
01-04-2009, 01:37 PM
I bought a pair of 1.25" from AOE:-

http://www.aoe.com.au/filters.html $25 for a pair.

I also bought a pair of 2" second-hand from this forum - they seem to have been sourced from a camera supplier.

pgc hunter
01-04-2009, 02:54 PM
The moon is uncomfortably bright in my 12", but I refuse to use an aperture mask because I'll be losing resolution. I just use a simple 1.25" moon filter and that does the job well.

xnomad
10-04-2009, 07:28 PM
I keep forgetting most of you have fast dobs. I've got a F/11.8 Mak so my 28mm 2" eyepiece is the shortest one that shows the whole moon. The next one down at 15mm 1.25" just misses out on the whole moon. So in theory I'd need two filters. I've had a look at my diagonal though and it appears to have threads for a filter. So it looks like I can get away with just a 2" filter in the diagonal for both barrel sizes. :)