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would a 4.25f/10 reflector show globulars easi

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#1 DJD57

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Posted 21 October 2011 - 07:45 PM

would the 4.25f/10 reflector show most of the globular clusters in the messier list as mostly resolved? dale

#2 simpleisbetter

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Posted 21 October 2011 - 07:55 PM

Not exactly. I use a 4" ED refractor and not all the globulars resolve, and whether they resolve or not is dependent more on your transparency and seeing for a given night than on the aperture once you get down to these smaller sizes. But IF this scope you want has good optics (have you checked it yet?) then it's certainly a good way to challenge yourself, trying to push yourself and your observing skills to see more and get better.

I have to agree with almost all the other posters in your other threads on this, that you'll be better off with something like a Synta 4" f/9 ED or even the SVP 120 achromat refractor on the stable and proven SVP mount, or an Orion 4.5" or 6" Skyquest dob than the Edmund. I fear you would be unhappy with it and regret it Dale.

#3 star drop

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Posted 21 October 2011 - 08:49 PM

would the 4.25f/10 reflector show most of the globular clusters in the messier list as mostly resolved? dale

No.

#4 DJD57

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Posted 21 October 2011 - 09:38 PM

i will see first and check it out dale

#5 blb

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Posted 21 October 2011 - 10:28 PM

would the 4.25f/10 reflector show most of the globular clusters in the messier list as mostly resolved? dale

No.


The answer is NO! At high power many Of the Messier globular clusters show some stars around the edge with averted vision and some clusters look a little grainy but none are fully resolved. You will need an 8" to 10" to start seeing many stars from a dark site, and they still are not fully resolved.

#6 DJD57

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Posted 21 October 2011 - 10:41 PM

ok thanks i guess i stick with the moon and planets only with the 4.25 scope dale

#7 BoriSpider

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Posted 22 October 2011 - 09:00 AM

There is a lot more to see than Moon and planets with
a 4" scope. Don't give up.

#8 DJD57

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Posted 22 October 2011 - 09:10 AM

ok doube stars and Tell me what else is good in this scope? dale

#9 blb

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Posted 22 October 2011 - 10:42 AM

ok doube stars and Tell me what else is good in this scope? dale


Anything you won't to look at. Some things look better with a larger scope but you can see about anything you like with a 4" scope.

I can't get over the fact that you say you have been doing this for 35 years and still ask questions like this.

#10 DJD57

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Posted 22 October 2011 - 11:01 AM

I have never had a 4inch relfector i have had a 6inch and nothing smaller than a 6inch so this could be a disappointing scope? dale

#11 star drop

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Posted 22 October 2011 - 11:31 AM

I basically started out with an Astroscan (4.25" reflector) and I would not describe the views as disappointing. Dale, do you still have a telescope or binoculars?

#12 DJD57

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Posted 22 October 2011 - 12:10 PM

I Got a c-8 and a discovery 10f/6 Pdhq relfector dale

#13 David Knisely

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Posted 22 October 2011 - 12:12 PM

would the 4.25f/10 reflector show most of the globular clusters in the messier list as mostly resolved? dale


It can show many stars in the brighter Messier globulars but won't make them mostly resolved. M22 will show many stars in its outer haze, although in a 4.25 inch aperture, the core may still look a little hazy. Another easy Messier globular is M4, which will show a hazy bar across the middle of the cluster as well as many stars in the outer haze (although again, not well resolved). To get better resolution, you may need an aperture in the six to eight inch range or larger. Clear skies to you.

#14 azure1961p

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Posted 22 October 2011 - 05:57 PM

No. M13 is partial with a dozen stars gimmering in and out and sometimes none. M15 showed marginal periphery res of a half dozen stars. Thete is utterly NO comparison between that scope and a 4" apo. Truth be told, my 70mm achro shows fainter stars than that scope ever did and under lesser skys. It is closer to a 60mm refractor on light gathering power as the coatings are poor.

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#15 Matt2003

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Posted 22 October 2011 - 06:31 PM


It might be Dale, but the again...
All the experience I've gained in the last 15 or 16 months (mostly since coming to CN! :))has taught me how to see more with smaller instruments than my 8inch Dob. Getting great views of stuff like the Veil Nebula & the North America Nebula in a pair of 50mm Binos rocked! LOL

Clear Skies,
Matt

#16 DJD57

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Posted 22 October 2011 - 07:08 PM

THANKS DAVID dale

#17 DJD57

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Posted 22 October 2011 - 07:09 PM

that does not sound good at all? dale

#18 DJD57

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Posted 22 October 2011 - 07:10 PM

yes the north american nebula is nice in my 20x80mm binos too dale

#19 azure1961p

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Posted 23 October 2011 - 06:52 AM

A fringey aperture where a scope shows a reasonable comparison of m13 to its photos is had with 6". At eight inches and over its better than its pics. Inthe four inch range its still captivating but with far fewer stars and a lot of unresolved stellar haze.

Pete

#20 JIMZ7

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Posted 23 October 2011 - 08:51 AM

Stick with your 8" & 10" scopes for globulars. Only M-13,M-22,M-3,M-4,M-5,M-92 will be worth the try resolving in a 4.25" reflector at higher powers,but again why go "smaller" on these objects when you got "bigger"!

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#21 DJD57

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Posted 23 October 2011 - 11:11 AM

i have a discovery 10f/6 scope too and m-13 is awesome totally dale

#22 DJD57

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Posted 23 October 2011 - 11:12 AM

yep i will be getting a celestron 9.25 sct scope too dale

#23 azure1961p

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Posted 23 October 2011 - 11:23 AM

Then what are you bothering with a 4.25" edmund? I thought you wete getting a 10" f/6 and you so desperatley needed to kno if it would resolve enckes.

Pete

#24 DJD57

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Posted 23 October 2011 - 10:57 PM

well pete i traded the discovery 10f/6 for a compact more portable celestron 9.25 sct scope dale

#25 JIMZ7

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Posted 24 October 2011 - 03:46 PM

Hey Dale you can trade with me. The Celestron 9.25" SCT will have lots of focal length for higher powers for sure.

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