lambermo
member
Reged: 07/16/07
Posts: 58
Loc: .nl
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While looking for info on commercially available mounts I found no clear overview, so I started one and put it online : Crude astro photography mount performance overview .
I hope this is of use to someone. The list has 37 mounts so far, and I'm sure I've missed some 
If you have corrections, additions or requests just PM me, or post them here, and I'll update the overview.
-- Hans
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gnowellsct
professor emeritus
Reged: 06/24/09
Posts: 733
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Your Ovision G11 post is the minimum spec advanced by Ovision. Results on the Losmandy group are more similar to this:
http://www.astromart.com/articles/article.asp?article_id=663
Very nice of you to put all this data together. If I had to summarize Ovision results I'd say the usual range is 3 to 7 arc seconds peak to peak with a smooth easily guided curve. We have reports on the group of sub-arc second tracking with PE and autoguiding engaged.
regards
Greg N
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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bardo
member
Reged: 09/13/09
Posts: 53
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wow that is really cool!! it would be great to get more graphs like the one site as well. ya know to get a average and all.
thanks for the effort!!
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rmollise
Post Laureate
Reged: 07/06/07
Posts: 4585
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Quote:
While looking for info on commercially available mounts I found no clear overview, so I started one and put it online : Crude astro photography mount performance overview .
I hope this is of use to someone. The list has 37 mounts so far, and I'm sure I've missed some
If you have corrections, additions or requests just PM me, or post them here, and I'll update the overview.
-- Hans
I don't have all these mounts, but I have used most of 'em. One in particular I take issue with is the CG5. You quote a PE of 80 arc seconds and a max load (for imaging, I assume) of 13 pounds. Certainly you may have tested a bad one, but I've yet to find one with a PE over 30-arc seconds, and while keeping the weight down is good, you can most assuredly image with well over 13 pounds onboard. Ask the folks taking pictures with the 10-inch Newtonian.
Same thing with the EQ-6. I've yet to see one with a 90 arc second PE. It doesn't matter whether its badged as a Pro, an Atlas or what, it is the same mount, so I assume something was wrong with the Atlas you tested or something went wrong with the test.
Yes, I know you are surveying various peoples' mounts, but that does very little good without a large number or, at least, without knowing what the person's methadology was.
All this says right now is that somebody has a bad mount or didn't know how to evaluate it.
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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Luigi
Post Laureate
Reged: 07/03/07
Posts: 4947
Loc: MA
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>>> max load (for imaging, I assume) of 13 pounds<<<
It shows 13 kg = 28 lb.
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17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha.
Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins
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bardo
member
Reged: 09/13/09
Posts: 53
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just a thought here but how about we get a thread going and stickied with everyones PE graphs from their personal mounts? its the all so important issue when considering a mount so to me it makes sense. 
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rmollise
Post Laureate
Reged: 07/06/07
Posts: 4585
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Quote:
just a thought here but how about we get a thread going and stickied with everyones PE graphs from their personal mounts? its the all so important issue when considering a mount so to me it makes sense.
Unless you could get more than a few respondents with a particular mount, the results are not gonna be terribly useful.
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Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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rmollise
Post Laureate
Reged: 07/06/07
Posts: 4585
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Quote:
>>> max load (for imaging, I assume) of 13 pounds<<<
It shows 13 kg = 28 lb.
OK...but the _rest_ of my finger-waggin' stands. 
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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AlanT
sage
Reged: 08/20/07
Posts: 488
Loc: 122º36' W, 47º37' N, WA USA
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Quote:
just a thought here but how about we get a thread going and stickied with everyones PE graphs from their personal mounts? its the all so important issue when considering a mount so to me it makes sense.
This sounds like a good idea to me too. Actually what's more important to me is the guided performance. I'd like to know what the raw PE is, but I'd like to see the graph that shows the average guiding performance and the raw guiding data so the smoothness of the drive shows through. An example is attached - This is my CGE prior to doing work on the RA servomotor. I don't remember the unguided PE of the mount... but I'm thinking it was something like +/- 10" without PEC.
It would have to be understood that what we'd see is a combination of the quality of the mount, the guiding hardware, and guide software settings. Still, it would be very informative.
al
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al
Meade 80mm APO
Celestron 6" SCT
CGE, GM-8, & CG-5 GT
ST-2000xcm, DSI Pro II, DSI Pro
( www.alberts-astro.com/astro )
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WillEyedOney
newbie
Reged: 09/15/04
Posts: 4
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When are you going to buy one though H?????? 
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lambermo
member
Reged: 07/16/07
Posts: 58
Loc: .nl
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Quote:
Your Ovision G11 post is the minimum spec advanced by Ovision.
Right, I did that on purpose. For all entries to be able to compare.
Ideally I'd like to add average numbers, a graph to show smoothness, all results after PEC, and results after active guiding. Maybe even prices in dollars next to euros
Quote:
Results on the Losmandy group are more similar to this:
Thanks. Added to the list.
Quote:
Very nice of you to put all this data together.
Thanks. I hope to learn from it and also that it's useful to someone else.
-- Hans
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lambermo
member
Reged: 07/16/07
Posts: 58
Loc: .nl
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Quote:
...the CG5. You quote a PE of 80 arc seconds
I found it to be high too, however I only found 1 proper PE measurement, so I put that in the list.
Quote:
but I've yet to find one with a PE over 30-arc seconds
Sounds reasonable, but I need a PE measurement to point to as I don't have access to this mount. The same goes for the EQ-6.
-- Hans
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chicot
super member
Reged: 09/30/08
Posts: 189
Loc: Liverpool, UK
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Interesting list. As you acknowledged, peak-to-peak error by itself is not always the whole story. For instance, my LX200 with trained PEC has an error of about 7 arcseconds, which is in line with what you stated. However, it has some extremely choppy PE that is more-or-less impossible to guide out without active optics. The Tak em200, on the other hand, has an error of 10 arcseconds but this is so smooth it can easily be guided out. Not quite sure what you can use to indicate the smoothness of PE.
Never heard of the ASA mounts, but their website is very interesting. 0.68 arcseconds over a period of hours???!!!
That's stupidly good.
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Meade 10-inch LX200 classic
Williams Optics ZII80
Starlight Xpress SXV-H9
Starlight Xpress Lodestar autoguider
Meade DSI III
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Doubleglaze
sage
Reged: 11/01/07
Posts: 201
Loc: Pacific NW
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Thanks for the work that went into this list. I'm also in the market for a new mount and am evaluating the options and costs. Really helps to have everything in one place to guide my thoughts. Some of the pricing is a bit off (I'm US based) but very useful none the less.
Mark
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Vixen VMC260L / Sphinx SXD
Pentax 75 SDHF
Canon 40D / 50mm f1.4 / 100mm f2.8 macro / 28-135 f/3.5-5.6 / 200mm f2.8L
http://www.astrophotogallery.org/showgallery.php/cat/500/ppuser/166
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