Contemplating selling my Orion Astroview 120EQ and getting an Orion 8" or 10". I live in a suburban area with street lights. How much difference would I notice? I never looked through a big DOB before. No interest in photography so Eq mount is a hinderance and I like the idea of the eyepiece on top. I am mechanically inclined so collimation should be no problem. Thanks.
moving from Orion Astroview120EQ to 8" or 10"
Started by 8borerifle, 01/06/2005 04:25PM
Posted 01/06/2005 04:25PM
Opening Post
Posted 01/06/2005 08:20PM
#1
Gary, no matter where you live, the increase in aperture will bring in a lot more objects, or make them much brighter for you, depending on what it is you are looking at...
If there are any Astronomy Clubs in your area, I would personally recommend trying them out, as you might be able to see some of these big scopes in person and get a good feeling for them...
Clear skies, and good luck!
Ivan
8)
If there are any Astronomy Clubs in your area, I would personally recommend trying them out, as you might be able to see some of these big scopes in person and get a good feeling for them...
Clear skies, and good luck!
Ivan
8)
Ivan Gastaldo 8)
Coconut Creek, FL
Ivan's Observatory
Lat 26N 16' 48" Long 80W 10' 48"
[COLOR="Red"]Personal Website:[/COLOR] http://www.ivangastaldo.com
CCD Imaging and Processing/Deep Sky - Moderator
I like to complain about everything - Moderator
Posted 01/06/2005 11:17PM
#2
Gary, the Columbus (Ohio) Astronomy Society has lots of members (330 or so) and tons of telescopes. I personally have an 80mm refractor, 8" SCT (and a 14" dobsonian on the way).
If you'd like to visit the club, contact me via PM and I'd gladly meet up with you there. I moved from an ETX90 to an 8" dobsonian a few years ago and LOVED it... there isn't much comparison really.
If you'd like to visit the club, contact me via PM and I'd gladly meet up with you there. I moved from an ETX90 to an 8" dobsonian a few years ago and LOVED it... there isn't much comparison really.
Posted 01/07/2005 01:10AM
#3
Gary:
I owned an Astroview 120EQ for a year or so. During that same time I owned an Orion XT-8 and a 12.5 inch Discovery DOB. (Still have both those.) I live in urban San Diego where the skies overhead are mag 4.2 on the best night with lots of light pollution as one would expect in a city of 1.3 million.
I did take the time to compare the XT-8 with the Astroview 120. I did like the Astroview and it did give good views.
Planets: The 120mm F8.3 scope did give nice views of Jupiter and Saturn but the false color was definitely evident and at high magnfications on a good never was quite a sharp and clear as the XT-8. On the plus side, the Astroview did not have collimation and cool down issues.
Double stars: I would have to give the edge to the Astroview 120mm here. It was probably not a match for the resolving power of the XT-8 when it was cooled and ready to go but the views were definitely more pleasing. Thermal issues seemed to make those double stars somewhat less than perfect in the XT-8. I was able to split Porrima a few years ago when it was about 1.3 arc seconds with the refractor.
DSOs: No doubt about the winner here. The factor of 2.8 in light gathering really allowed the XT-8 to perform better on the DSOs from my back yard. Stuff was just much brighter in the XT-8. From my backyard I could see the planetary in M46 with the newt quite regularly but never with the refractor.
Ease of setup: The DOB was faster and easier.
Ease of use: Viewing the zenith with the refractor pretty much required me to get down on my knees in the dirt, not nice.
Other issues: The DOB mount is much more solid than the Astroview. I had the dual drives for the Astroview and at 100x the mount would vibrate with each tick of the RA motor and in order to get a clean split of the double-double I had to turn the drive off. A seriously better tripod solved this problem.
Why I sold the Astroview 120EQ: It just seemed that I did not use it. It was not worth the effort to set it up because the XT-8 was more comfortable and all around a better performer.
I still have the mount which is performing nicely with Super Polaris wooden legs and an Orion Space Probe 130ST.
What I would do were I in your situation:
These days the XT-8 gets little use because I happened upon one heck of deal ($240 via Astromart)on an OPT Starhunter 10, same as the Hardin DSH 10 inch.
I really like this scope. Physically its significantly bigger than the XT-8 but it is still small enough to be easily moved about and it will still fit in my Ford Escort for a trip to the mountains.
Optically that extra aperture is enough to dig out more faint fuzzies from my urban sky and I like the job this scope does on the planets.
While it doesn't have quite the umph that the 12.5 incher does, it still does an amazing job and because of its nice size, it gets more use than either of the other two scopes.
So, were I in your shoes, it would be either a Hardin 10 inch DOB or an Orion 10 inch DOB.
Warning: I do like DOBs, so do, some don't. Take what I have to say with more than one grain of salt. The advice to head for a star party is good, see this stuff in action, a 10 inch DOB is an easy setup for most folks but not all.
Be clear that a larger scope like a 10 inch DOB will not perform properly until it has cooled down. This might take an hour or more. Be clear that collimation is an issue. These scopes do require collimation every so often. Mine seems to stay in collimation quite nicely.
And be clear that a 10 inch Newtonian will do some wonderous things when the seeing is good and the scope is cooled and collimated...
Best wishes,
Jon Isaacs
I owned an Astroview 120EQ for a year or so. During that same time I owned an Orion XT-8 and a 12.5 inch Discovery DOB. (Still have both those.) I live in urban San Diego where the skies overhead are mag 4.2 on the best night with lots of light pollution as one would expect in a city of 1.3 million.
I did take the time to compare the XT-8 with the Astroview 120. I did like the Astroview and it did give good views.
Planets: The 120mm F8.3 scope did give nice views of Jupiter and Saturn but the false color was definitely evident and at high magnfications on a good never was quite a sharp and clear as the XT-8. On the plus side, the Astroview did not have collimation and cool down issues.
Double stars: I would have to give the edge to the Astroview 120mm here. It was probably not a match for the resolving power of the XT-8 when it was cooled and ready to go but the views were definitely more pleasing. Thermal issues seemed to make those double stars somewhat less than perfect in the XT-8. I was able to split Porrima a few years ago when it was about 1.3 arc seconds with the refractor.
DSOs: No doubt about the winner here. The factor of 2.8 in light gathering really allowed the XT-8 to perform better on the DSOs from my back yard. Stuff was just much brighter in the XT-8. From my backyard I could see the planetary in M46 with the newt quite regularly but never with the refractor.
Ease of setup: The DOB was faster and easier.
Ease of use: Viewing the zenith with the refractor pretty much required me to get down on my knees in the dirt, not nice.
Other issues: The DOB mount is much more solid than the Astroview. I had the dual drives for the Astroview and at 100x the mount would vibrate with each tick of the RA motor and in order to get a clean split of the double-double I had to turn the drive off. A seriously better tripod solved this problem.
Why I sold the Astroview 120EQ: It just seemed that I did not use it. It was not worth the effort to set it up because the XT-8 was more comfortable and all around a better performer.
I still have the mount which is performing nicely with Super Polaris wooden legs and an Orion Space Probe 130ST.
What I would do were I in your situation:
These days the XT-8 gets little use because I happened upon one heck of deal ($240 via Astromart)on an OPT Starhunter 10, same as the Hardin DSH 10 inch.
I really like this scope. Physically its significantly bigger than the XT-8 but it is still small enough to be easily moved about and it will still fit in my Ford Escort for a trip to the mountains.
Optically that extra aperture is enough to dig out more faint fuzzies from my urban sky and I like the job this scope does on the planets.
While it doesn't have quite the umph that the 12.5 incher does, it still does an amazing job and because of its nice size, it gets more use than either of the other two scopes.
So, were I in your shoes, it would be either a Hardin 10 inch DOB or an Orion 10 inch DOB.
Warning: I do like DOBs, so do, some don't. Take what I have to say with more than one grain of salt. The advice to head for a star party is good, see this stuff in action, a 10 inch DOB is an easy setup for most folks but not all.
Be clear that a larger scope like a 10 inch DOB will not perform properly until it has cooled down. This might take an hour or more. Be clear that collimation is an issue. These scopes do require collimation every so often. Mine seems to stay in collimation quite nicely.
And be clear that a 10 inch Newtonian will do some wonderous things when the seeing is good and the scope is cooled and collimated...
Best wishes,
Jon Isaacs
Funding Member
