Kapin
journeyman
Reged: 12/01/07
Posts: 8
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Hi, all my apologies first because this question has surely been asked before. I searched this forum briefly but couldn't find much.
I’m relatively new to telescope astronomy and very new to observing the moon. I was happy with binoculars for a long time. Please give your recommendations for filters for observing the moon. I'm not looking for a bargain, good quality is more important. Filters I’m likely to keep, especially when I move up to bigger telescopes.
Equipment: WO Megrez 90 and their UWAN 16mm & SPL eyepieces 12.5, 6 and 3mm.
Thanks in advance
Kapin
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revans
scholastic sledgehammer
Reged: 09/26/05
Posts: 811
Loc: Fitchburg, MA
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Hi,
Sorry if this is a re-posting... it didn't appear to go through the first time...
Anyway, my recommendation to you is an unusual one and likely not many experienced observers would agree with me here...
I suggest that you buy a few narrowband filters over the internet from someone like Knight Optical in the UK (the were the least expensive when I shopped around a few years ago). I recommend 25 mm diameter filters at say 450 nm, 750 nm and 950 nm with a bandpass width of 10 nm (i.e. +/- 5 nm).
There is more discussion of this approach and what you can learn about lunar geology from it on my website at:
www.freewebs.com/revans_01420
I recommend this approach over the usual approach of using red, blue, green, yellow, orange, and "moon" filters which are not as useful from my point of view.
I use these 25mm filters in a Lumicon 5 filter holder and I place them into standard True Technology 1.25 inch clear BK glass screw-on filter holders. I use thin rubber washers to block the millimeter around the edges not covered by the bandpass filter.
Anyway, that is just my recommendation... others will most likely recommend the more classical approach using broadband colored filters or a neutral grey light blocking filter of some sort.
Rick Evans
The 950 nm filter will be most useful via photography since this wavelength is beyond the range of our vision.
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Rick Evans
http://www.freewebs.com/revans_01420/
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30032
Loc: Tucson, AZ
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If you're talking visual observing, and not imaging of some sort, the only filter I use with my 8" reflector is a variable polarizing filter. There are several such available, of which I happen to use the Orion VPF. All a VPF does is cut down the glare, making the Moon easier to study at low to medium powers for long periods of time. At higher magnifications, you may find that eye strain caused by glare is not a problem.
I have dabbled a bit with color filters but not used them extensively, so others may want to advise you on such.
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Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
Alcohol and calculus do not mix. Please don't drink and derive.
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Stephen65
scholastic sledgehammer
Reged: 04/14/07
Posts: 934
Loc: Melbourne, Australia
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I don't use any filters for observing the Moon.
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Megrez 90
FLT 132
Mewlon 250
Lots of XWs, an Ethos, Supermonos and some other EPs
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Arbacia
sage
Reged: 04/18/07
Posts: 383
Loc: Madrid, Spain
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I am using almost any filter of my collection.
Most used are:
-neodymium (BG20) for general observing
-Double Polarizer (=variable Polarizer) useful to show the moon to other people. I don't like for my own observation. Great light scattering (Meade var. Pol.)
- Baader Red RG610 most used to see Maria lava formations and crater rays.
- Baader yellow GG495: some days to reduce the atmospheric glow. Occasional use.
- Baader dark blue BG14. Used as a contrast to baader red. Most useful to contrast maria basaltic formations
- Meade Nebula Narrowband 908N or an UHC by Omega Optical. I use any of them (more fequently the Omega) and usually stacked with Baader Red. When UHC is stacked with the red the resut is a narowband in the far red.
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LightBridge 12"
Celestron C8 (orange tube) on HEQ5
Set of Hyperion EPs; DMK 31AF03.AS
CN image gallery
http://www.asociacionhubble.org
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chascar
sage
Reged: 02/14/05
Posts: 315
Loc: Franklin Massachusetts
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Hi Kapin I was not a big believer in filters for luna til a guy at my club hooked up a red and then orange filter to the club scopes on a night when the bright moon precluded any real DSO work and all i can say is you will see a big diffrence with those two recommendatons.
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Charles
42.1N 71.4W Member Skyscrapers Inc.
Meade 628/f8 w 80mm guide
Meade ETX 90 EC
Tasco 9TE-5
Swift 7x50 Seahawks
Nikon 10x35 6.6 WF
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stevecoe
Reged: 04/24/04
Posts: 2129
Loc: Arizona, USA
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Howdy;
Red filters really bring out the mare...great contrast.
Variable polarizer for glare. Orion sells a good one, I have an old Riverside special with no name, but it still does just fine.
I have not found any other colors of filter to be helpful.
Take Care;
Steve Coe
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150mm 6" f/8 Celestron Refractor on Sirius Mount
80mmED 3" f/7.5 Orion Refractor
Author "Deep Sky Observing" Springer-Verlag
Author "Nebulae and How to Observe Them" Springer
New Canon Xt astrocamera with Hutech modification
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Carol L
Reged: 07/05/04
Posts: 5880
Loc: Tomahawk, WI 45N//89W
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Except for the polarizing filter, the only one I've found useful is the deep red one. I use it during daytime lunar work and it does a good job of helping increase the contrast while keeping the blue dayglare down.
But basically all it really does is make things easier for me to see. From my experience, no filter has ever 'allowed' me to see lunar features.. they just make certain ones 'pop' a bit more.
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 *Step-by-Step Lunar Sketching*
CN Gallery
Photo Gallery
8"SCT ~ 120achro ~ 90Mak ~ 80ST ~ 11x70s ~ 22x100s
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Arbacia
sage
Reged: 04/18/07
Posts: 383
Loc: Madrid, Spain
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Carol, you are right: in the moon the filter just make certain ones 'pop' a bit more. They don't enhace dramatically the view. However Moonlight is sometime very intense and better than variable Polarizer I preffer Deep red or Red deep+UHC as they reduce the glares and enhaces contrast in mare materials and rays.
Respect to the red filters, I just posted a image in this sub-forum of lunar observation.
"Mare Nubium. Lava flows. False colour."
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=2238484
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LightBridge 12"
Celestron C8 (orange tube) on HEQ5
Set of Hyperion EPs; DMK 31AF03.AS
CN image gallery
http://www.asociacionhubble.org
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revans
scholastic sledgehammer
Reged: 09/26/05
Posts: 811
Loc: Fitchburg, MA
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Actually, filters can make all the difference in the world. For example, check out the view of Tycho crater on this USGS website:
http://astrogeology.usgs.gov/Projects/Clementine/
Of course, I'm talking about imaging work rather than purely visual work here...
Rick Evans
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Rick Evans
http://www.freewebs.com/revans_01420/
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proud uncle
Pooh-Bah
Reged: 01/22/07
Posts: 1336
Loc: Central Texas
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Quote:
Except for the polarizing filter, the only one I've found useful is the deep red one. I use it during daytime lunar work and it does a good job of helping increase the contrast while keeping the blue dayglare down.
Carol, do you use the red at night for bringing out contrast in lava flows, as others have suggested?
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Kenneth
Zhumell 10" Dobsonian (f/4.9)
2" 32mm WA eyepiece
9mm, 12.5mm, and 20mm Plossls
6mm TMB/BO Planetary
2" 2x ED Barlow
Nikon 10x50 binocular (6.5 deg FOV)
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Carol L
Reged: 07/05/04
Posts: 5880
Loc: Tomahawk, WI 45N//89W
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No, I don't Kenneth.
From my experience, a unfiltered view gives my brain the same amount of information to process as a filtered one does. Besides, I'm a big believer in minimizing the amount of glass between the target and my eye, which is why I also prefer viewing without a diagonal. 
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*Step-by-Step Lunar Sketching*
CN Gallery
Photo Gallery
8"SCT ~ 120achro ~ 90Mak ~ 80ST ~ 11x70s ~ 22x100s
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revans
scholastic sledgehammer
Reged: 09/26/05
Posts: 811
Loc: Fitchburg, MA
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Carol,
I agree that for visual work filters are of little value unless you are using a really large telescope or are viewing close to full moon. However, I strongly believe that for photographic work filters are important. In my previous post to this thread I mention the USGS images of Tycho taken using various filters. If it were not for the use of these filters, the fine reticulated pattern on the floor of the crater would not have been suspected at all from the unfiltered view. I think that filters are important to reveal such subtle features and also to define which lunar features are rich in iron. I am not talking about the usual filters that amateurs use (red, blue green, orange etc.) but about wavelength specific filters.
Rick Evans
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Rick Evans
http://www.freewebs.com/revans_01420/
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Carol L
Reged: 07/05/04
Posts: 5880
Loc: Tomahawk, WI 45N//89W
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Hi Rick, I understand about using filters for photography, but the original poster asked for "recommendations for filters for observing the moon." My work is mostly observational, so that's all I can comment on.
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*Step-by-Step Lunar Sketching*
CN Gallery
Photo Gallery
8"SCT ~ 120achro ~ 90Mak ~ 80ST ~ 11x70s ~ 22x100s
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geoffrey
sage
Reged: 01/05/04
Posts: 358
Loc: North West England
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Hello all,
Just caught this. I have only had a quick look at the Moon with my new "Moon Filter" and did not like what I saw at all. Started at 100x and then went up.
Is a "bog standard" moon filter a VPF or something different? Mine appears to a "of a Grey nature" but gives a slightly blue cast on observing. It was not particularly cheap as such, and is stamped "Moon" Using it appeared to make the image less sharp also.
Thanks and regards
Geoffrey
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Celestron Nextstar 8SE
6.25" F7.6 Dob
Skywatcher ST80
Opticron imagic BGA PC ASF T 8x42
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dgs©
Postmaster
Reged: 03/29/04
Posts: 13903
Loc: West Monroe, Louisiana
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The VPF is Variable Polarizing Filter... you can adjust how much dimming you get by turning the two halves of the filter, with respect to each other, for more or less polarizing. It looks dark grey, and I've not noticed any blue tint when using it. 
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- david
8"Ø Newtonian on SVP, Moonlite CR2, Telrad
PST Oberwerk Ultra 15x70 Orion Ultraview 10×50
Hand-me-down Sears Refractor (Discoverer) 60mm×900mm
"What we have done for ourselves alone dies with us; what we have done for others and the world, remains and is immortal." --Albert Pike
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geoffrey
sage
Reged: 01/05/04
Posts: 358
Loc: North West England
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Thank you folks.
Geoffrey
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Celestron Nextstar 8SE
6.25" F7.6 Dob
Skywatcher ST80
Opticron imagic BGA PC ASF T 8x42
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Tim2723
The Moon Guy
Reged: 02/19/04
Posts: 5121
Loc: Northern New Jersey
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Hi Kapin,
While you'll find observers using all sorts of filters for various reasons, given the last line of your original post (fiters you'll use with bigger scopes), I think it's safe to say that the VPF is the most popular and agood bet for a lifetime sort of filter. They are used for bright planets in large scopes as well, so they are really useful to have in the kit.
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The crwth will set you free!
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