johnfdean
Pooh-Bah
Reged: 06/04/06
Posts: 1073
Loc: southern tip of Illinois
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One very cold night in northern MN I got up to 50x per inch.
It was one of those rare nights from all directions. It was around 35 below. I was with a newby and everything I pointed at I hit first time.
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Celestron C6 f/5 by Vixen with Polaris GEM
14" Tscope dob f/4.7 with Argo Navis
80mm Nighthawk on Eq 2
Celestron C-4 f/10
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clitherowclan
professor emeritus
Reged: 02/23/05
Posts: 736
Loc: Fife Scotland
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It's a funny thing about the difference between imaging and observing. I know that I can pull out more detail from a good, well focused, avi file (and make a fine image from it) than I ever remember seeing at the eyepiece with one eye. But I have noticed that if I use bino-viewers my brain is assembling real time images that are at least as good if not better than the ones I can get from my imaging runs. I'm guessing two eyes are much better than one and at least as good as a Philips webcam!
Cheers,
Alan C.
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Scottish Astronomer, Firstlight Instruments 10 inch F6.3 Newtonian, Helios 8inch F5 Newtonian and ED80 Apo on driven EQ5. Various cheap cameras.
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pennyandchris
professor emeritus
Reged: 01/30/07
Posts: 677
Loc: Horsham, England
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On really good nights up to 600x in my Mak. Usually less than 200x in both scopes due to seeing.
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Orion UK OMC140 Mak Cass
TeleVue Ranger
Coronado Ha and CaK PSTs
Meade LXD75 mount
Ambermile alt-az mount on wooden surveyors tripod
Manfrotto 074 photo tripod with 501 head
+ various binocs
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astroghlo
member
Reged: 03/01/09
Posts: 51
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Because of the seeing in most cases I'm only able to go 125x-175x at the most .
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astroghlo
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azure1961p
scholastic sledgehammer
Reged: 01/17/09
Posts: 761
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In a properly collimated 10" reflector with good to excellent optics and preferably a small central obstruction, I'd say about 600x. The conventional wisdom is that the sky limits everything to around 500x - I think that's kind of unnecessarily putting a cap on things. While it is a good rule of thumb most of the time, I'd wager - though I havent done it, there are evenings where 600x in that size scope is effective.
In my planetary reflector for comparison, I've topped out around 364x-432x on lunar with a definite lean over 400x.
Quite simply, the finer craterlets were more evident at those magnification as they blipped in and out of view with the seeing.
Lastly, dont forget - the highest useful magnification prefered is a subjective thing ultimately. I know some astronomers who just, frustratingly to me, eek along at these medium magnifications in the best seeing [250x in an 8"] when I know in my heart the scope would show things plainer at well higher.
Alas, those evenings are few and far between. I averege about four nights or less out of the entire year when those miraculous nights arrive. Often in summer, and oddly in winter sometimes.
Pete
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azure1961p
scholastic sledgehammer
Reged: 01/17/09
Posts: 761
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To put things on balance by the way, I'd say averege magnifications on the moon for me are 175x to 240x. When I can go to 312x and its as sharp as 240x normally is, I get quietly giddy as I know magic can happen that night. Though generally, 175x in softer seeing, 240x in better average seeing and 200x on so-so nights.
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Jim Rosenstock
Post Laureate
Reged: 07/14/05
Posts: 4186
Loc: MD, south of the DC Nebula
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A magnification is "useful" if it makes you happy.
It's your eyes that count; others' opinions on this matter are unimportant.
Cheers,
Jim
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David Knisely
Postmaster
Reged: 04/19/04
Posts: 8793
Loc: Beatrice, Nebraska
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Quote:
A magnification is "useful" if it makes you happy.
It's your eyes that count; others' opinions on this matter are unimportant.
Cheers,
Jim
I would not say that the opinions of others are unimportant, although it does often come down to personal preference. A plain fact is that if you go too high, the moon will appear somewhat fuzzy with less than sharp detail, and things like floaters and seeing will become problems. The exact magnification where these things tend to become a little too bothersome is a point of some debate, but eventually, with increasing power, the observer will reach that point. Clear skies to you.
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
Prairie Astronomy Club
http://www.prairieastronomyclub.org
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Dr Morbius
scholastic sledgehammer
Reged: 02/06/07
Posts: 1821
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Quote:
the highest I got on the moon with satisfactory results was 400x. Usually, I am at around 200-250x however, as seeing (like the weather) in my area is complete garbage 99.999999999% of the time.
99.999999999% of the time? Lucky you! ......I gotta move to New Mexico! 
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Meade ETX-125
NightFire 6" f/8 Refractor with Moonlite focuser
Meade 14" LX200 S/C
D&G 10" f/15 Refractor with Parallax Mount
Little Giant 11x70mm Binos
I'm afraid of dying, but I've learned to live with it. ......Steve Perry
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viking 10
sage
Reged: 02/07/09
Posts: 237
Loc: middeltown,N.Y>
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at 250x with my 5mm tmb the views are amazing just got the 3.2mm ill post when i can get to use it.It will give me 390x!!!!!!!!
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Zhumell 10" TMB 3.2, 5 and 8mm planetary's skyscout and a bunch of cheap plossel's
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desertstars
Please stand by...
Reged: 11/05/03
Posts: 35868
Loc: Tucson, AZ
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Something to remember when pushing the magnification beyond what you usually use: be patient. I've observed the Moon on good nights using a 6mm eyepiece with a 2x barlow (330x in round numbers) and seen some amazing details. But I had to sit there for a long time waiting for those moments when the seeing suddenly matched the magnification level. Most of the time things were more than a bit fuzzy (and this was under VERY good conditions), but when it cleared - whoa! Next best thing to being there. (I've also tried this with a 4mm and a 2x barlow, so 500x. That turned out to be taking a good idea way too far!  )
So don't be too quick to decide it isn't working. And be willing to try again another night. 
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Tom W.
Collinder's Catalog
Standing in a garden, contemplating the stars, and wondering how to put it all into words.
Carpe Lunam
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viking 10
sage
Reged: 02/07/09
Posts: 237
Loc: middeltown,N.Y>
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thanks ill be patient
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Zhumell 10" TMB 3.2, 5 and 8mm planetary's skyscout and a bunch of cheap plossel's
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desertstars
Please stand by...
Reged: 11/05/03
Posts: 35868
Loc: Tucson, AZ
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 Let us know how it goes.
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Tom W.
Collinder's Catalog
Standing in a garden, contemplating the stars, and wondering how to put it all into words.
Carpe Lunam
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Doug L
sage
Reged: 08/17/08
Posts: 217
Loc: Ottawa, Canada
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Dean, do you mean a fan blowing across the face of the mirror? I've just reread an old Sky & Telescope magazine (Jan.2002) and the article, "Thermal Management in Newtonian Reflectors" is the best I've seen on the subject. A simple modification with amazing results. I'm definitely going to do it to my 10 inch Dob.
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Bino reality... 1 + 1 > 2
Edited by Doug L (03/28/09 11:10 PM)
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