Lane
Post Laureate
Reged: 11/19/07
Loc: Frisco, Texas
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Which 8" dob would you buy?
#5716835 - 03/06/13 04:53 PM
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My brother and his wife were using my C8 a few weeks ago and now they are infected with the astronomy bug. They don't want to spend a lot and they want to learn how to star hop so they are not really that interested in a computerized scope.
I have suggested they start with an 8" dob. I was thinking Zhumell or Orion Classic. Which one of these would you choose and why? Or is there something else that might be a better starter scope for them? I think the Zhumell comes with a collimation tool, but is it any good and is a collimation tool really necessary for a small scope like this?
I am an SCT / Refractor guy, so not sure what to really look for here.
They will be carrying the scope about 100 yards to the open field behind their house. Their location is a Green Zone.
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KerryR
Carpal Tunnel
   
Reged: 12/05/07
Loc: SW Michigan
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Re: Which 8" dob would you buy?
[Re: Lane]
#5716851 - 03/06/13 05:04 PM
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I think either would be a fine choice-- I've had both. More similar than different. I think the Zhumells may come with more accessories.
They won't necessarily have to make a big deal out of super-accurate collimation, but they will need to be able to do it. A combination sight tube and cheshire will do the trick.
The only other thing I could mention is that there's nothing wrong with a 6" f8. These are nice because they (usually) fit in the back seat of a car with the base attached, and are easily carried with the base attached in one hand. This may or may not be of interest, but I find I use 'one handed' scopes more often than 'multiple handed'...
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JIMZ7
Pooh-Bah
   
Reged: 10/22/05
Loc: S.E.Michigan near DTW
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Re: Which 8" dob would you buy?
[Re: KerryR]
#5716863 - 03/06/13 05:11 PM
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Try Opticsmart.com. They sell Apertura Dobs which are nearly the same as Zhumells but you can get super upgrades on their Dobs. as I see in their videos.
Jim
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tezster
professor emeritus
   
Reged: 07/14/09
Loc: Missisauga, Canada
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Re: Which 8" dob would you buy?
[Re: JIMZ7]
#5716887 - 03/06/13 05:19 PM
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I agree - if I were in the same position, I'd be looking at an AD8
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BDS316
Carpal Tunnel
Reged: 09/16/09
Loc: Sol 3
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Re: Which 8" dob would you buy?
[Re: Lane]
#5716936 - 03/06/13 05:47 PM
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Definitely one of the GSO's. Zhumell, Apetura or Astro Tech from Astronomics with a CN discount.
Reasons for choosing a GSO over the Orion are several:
Better Dobsonian motions. I know this from personal experience, which is why I upgraded to an aftermarket dob mount
Better eyepieces. The 2 inch GSO 30mm SV is pretty good at f/6.
Better accessories, like a finder scope, eyepiece rack, and a fan.
I'm not going to list "better focuser" as a reason although many like the GSO 2 stage focuser better than the Orion's Synta single stage. At f/6 it really isn't that big a deal. The reason I upgraded to a Moonlite is because I got an older XT8 that had a rack and pinion.
Edited by BDS316 (03/06/13 05:51 PM)
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kfiscus
professor emeritus
   
Reged: 07/09/12
Loc: Albert Lea, MN, USA
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Re: Which 8" dob would you buy?
[Re: BDS316]
#5716951 - 03/06/13 05:54 PM
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Avoid the tension springs if possible. I like the Zhumell (and related) adjustable alt bearings.
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Pinbout
Post Laureate
   
Reged: 02/22/10
Loc: Montclair
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Re: Which 8" dob would you buy?
[Re: kfiscus]
#5716962 - 03/06/13 05:59 PM
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I would tell them to hurry up and buy the 8nf6 swayze refigured for 150 in the classifieds and send it to dobstuff to build the structure.
a custom doby with larger alt bearings make all the difference than those imports.
Edited by Pinbout (03/06/13 05:59 PM)
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Tophat3
member
Reged: 07/20/10
Loc: Columbus,Ohio
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Re: Which 8" dob would you buy?
[Re: Pinbout]
#5716971 - 03/06/13 06:04 PM
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Yep, Zhumell or Apetura.
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Lane
Post Laureate
Reged: 11/19/07
Loc: Frisco, Texas
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Re: Which 8" dob would you buy?
[Re: Tophat3]
#5717022 - 03/06/13 06:34 PM
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The Apertura AD8 looks like the way to go.
Thanks for your help guys
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RogueGazer
super member
Reged: 06/10/12
Loc: Central Point Oregon
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Re: Which 8" dob would you buy?
[Re: Lane]
#5717121 - 03/06/13 07:32 PM
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As a Z8 owner I have no problem recommending them but there are a few issues I have had.
The supplied laser collimater is of poor quality IMHO. If they go this route they will need to verify the collimater is collimated. Even after doing that it wobbles around so much it is hard to get a repeat placement of the laser on the primary. It goes through batteries like crazy. I actually replaced the internal laser pointer with a more efficient model and the batteries last way longer now. I still plan on replacing it eventually but it gets me by for now.
The primary mirror clips were way too tight. I could not achieve proper focus until I figured out the problem. I bought it new so this was done at the factory.
A lot of the external hardware was too loose. The worker who installed the mirror couldn't be the same guy who installed the rest of the hardware. I have the tension spring model which doesn't bother me but the 4 bolts attaching the ALT bearing assembly to the OTA would never stay tight until I used some locktite.
The build instructions are not the greatest but there is a video on Youtube that will help.
Other than those fully correctable problems I really like the scope. If they are going to carry it that far I would get a moving dolly and a small ratchet strap to secure it to the dolly. A couple shower caps on both ends will help keep the mirror clean during storage.
Edited by RogueGazer (03/06/13 07:35 PM)
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Ed D
Carpal Tunnel
   
Reged: 04/30/10
Loc: Sunny South Florida
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Re: Which 8" dob would you buy?
[Re: RogueGazer]
#5717154 - 03/06/13 07:53 PM
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If they're going to be carrying the scope 100yd I think an 8" or 6" Dob is going to get old really fast, unless your brother is built like an upside-down pyramid or they plan to use a cart to take the scope and accessories out. You may want to talk to them about this.
Ed D
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Lane
Post Laureate
Reged: 11/19/07
Loc: Frisco, Texas
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Re: Which 8" dob would you buy?
[Re: Ed D]
#5718729 - 03/07/13 04:05 PM
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He likes to build stuff and when I told him about the wheelbarrow handles used on the big dobs, he started planning how he is going to build a custom wheelbarrow just to haul the scope back and forth.
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Pinbout
Post Laureate
   
Reged: 02/22/10
Loc: Montclair
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Re: Which 8" dob would you buy?
[Re: Lane]
#5718759 - 03/07/13 04:25 PM
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if he likes to build stuff he can buy a kit from astro sky. He's having a spring sale also.
just think a custom dob with smooth movements...
and 8in's is easy to throw around.
or he can get a tube from HD or Lowes and make a tube dob and get a rocker box kit from astrogoods and still have that custom feel...
if he can make it why buy it.
and while he's building it he can get the companion 4" refractor...
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Jarrod
sage
   
Reged: 01/20/13
Loc: SE USA
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Re: Which 8" dob would you buy?
[Re: Pinbout]
#5718784 - 03/07/13 04:42 PM
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if he can make it why buy it.
A biologist and a physicist go to a pristine white sand beach. The biologist exclaims, "Look at all that beautiful sand! I'm going to make a sand castle!" The physicist exclaims "Look at all that beautiful sand! I'm going to make a telescope!".
Spoken like a true physicist.
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csrlice12
Post Laureate
   
Reged: 05/22/12
Loc: Denver, CO
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Re: Which 8" dob would you buy?
[Re: Jarrod]
#5718795 - 03/07/13 04:49 PM
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For the scope itself, I'd go for the Zhummel or Aptura. But as foar as the laser collimater that comes with it--just heave it as hard as you can....that's as close as it should ever get to collimating your scope...you're cat will get better mileage out of it...Outside of the laser, they are great scopes, and they have a better mount system then the Orion classic (God, when are they ever going to bring the teflon friction pads to the classic??)
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kfiscus
professor emeritus
   
Reged: 07/09/12
Loc: Albert Lea, MN, USA
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Re: Which 8" dob would you buy?
[Re: csrlice12]
#5719052 - 03/07/13 06:45 PM
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Troll alert... Buy the one that has a 12" mirror.
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Pinbout
Post Laureate
   
Reged: 02/22/10
Loc: Montclair
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Re: Which 8" dob would you buy?
[Re: Jarrod]
#5719228 - 03/07/13 08:03 PM
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Quote:
Spoken like a true physicist.
it more like a designer, I don't like this...I don't like that. Oh god why don't they do this. I guess I'll have to find a way to do it myself...
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bob irvin
sage
Reged: 03/22/11
Loc: Greater Los Angeles, CA
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Re: Which 8" dob would you buy?
[Re: RogueGazer]
#5720306 - 03/08/13 11:14 AM
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The supplied laser collimater is of poor quality IMHO. If they go this route they will need to verify the collimater is collimated. Even after doing that it wobbles around so much it is hard to get a repeat placement of the laser on the primary. It goes through batteries like crazy.
I agree on the above points. I purchased a Glatter TUblug to "nullify" the inability of the laser to snugly seat in the focuser for the primary mirror adjustment. I do like the scope, mine's a Z10.
bob
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csrlice12
Post Laureate
   
Reged: 05/22/12
Loc: Denver, CO
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Re: Which 8" dob would you buy?
[Re: bob irvin]
#5720369 - 03/08/13 11:54 AM
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It also doesn't go above the "no damage" setting......No heating rocks to stay warm, no stun setting, you can't even set it to overload.... 
+1 onthe Glatter/Tublug system......
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SteveG
Post Laureate
   
Reged: 09/27/06
Loc: Seattle, WA
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Re: Which 8" dob would you buy?
[Re: csrlice12]
#5720423 - 03/08/13 12:22 PM Attachment (18 downloads)
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I recommend the AstroTech version (same as Zuhmell only white). Much better motions than the Orion XT series. Nice, usable scope right out of the box.
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