Choice

[Mystikal]

Hello!!

WHich is better?

The GS-500 on SV1 mount
or the GS-580 or 600 on a Dob (same thing on a DOB mount I think).

SInce I am looking at getting a CG-5 Mount later on.... would the DOB be a better option?

Im scared, no GOTO!!

[ballaratdragons]

In all honesty Mystikal, the SV1 mount might let you down and frustrate you.

Whereas, a dob base is usually pretty solid, although no tracking easily accomplished.

Although both have the same apature I think the dob may be the better choice for ease of use. Unless you want to use the SV1 mount later on with a much lighter scope on it, and put the 500 on the CG-5.

[Mystikal]

HI Thanks for the quick response!!

With the Celestron CG-5 Mount (Goto version), would the OTA GS500 fit on it?

[ballaratdragons]

Easily. The CG-5 can carry quite a decent load for a smallish mount. Much more than a 6" reflector.

[ballaratdragons]

Whereas the SV-1 won't carry much load, especially with its aluminium legs.

But a nice little refractor on it would be a great 2nd scope or travel scope.

[Astroman]

I had an SW680 wich is skywatchers version of the GS-680, I got rings with mine but also made a dob base for it. It now sits happily on top of an EQ6, but a CG-5 would handle it no worries, it's only an 8kg tube. Since you say you are looking for the EQ mount later on, maybe the Dob would be a better option, atleast to get you going to learn more about the sky etc....

[rmcpb]

I agree with Ken, get the dob and mount it on the heavy EQ mount later on. Then you can switch between mounts as you need. The lighter mount will be VERY frustrating.

Cheers

[Mystikal]

Hi,

I think I'll go with a 8 or 10 in GSO DOB from Andrews.
Im just worried about portability. Will it fit safely in the back of a sedan?
How heavy would these be? I need portability. I will be transporting the scope often.
I've had a small refractor before, an ETX70, how would it compare to this? I know the apperture is massive compared to it, i enjoy wide fields of view and fairly sharp details whn inspecting planets closely.

Im prepared to buy at most the 10" Deluxe model. What do you all think?
Which eyepiece should I get?

[Dujon]

Hello, Mystical.

Many might say that a 10" Dobsonian mount is readily portable and, to an extent, it is. I cart mine outside when I get the chance without too many problems (dodging door jambs and the like). I do it in two stages though, as it's very cumbersome. From memory the tube and the mount both weigh around the 20Kg mark. The tube, due to its length, is awkward to manoeuvre in smallish places. At this point in time I have not attempted to load it into the back of my car but I suspect that it's going to be difficult until such time as I work out some sort of a system. The base (the Dob. mount) is bulky but more easily carried courtesy of a handle.

You will need to work out a way to secure the tube once it is in the car as you don't want that sort of mass ricocheting around the cabin should you come to a sudden halt. The seat belts could well work, but I'll leave that to others to comment upon. In my case (I have a hatchback) the base should fit readily into the rear luggage area.

I cannot comment on the ETX70 versus the 10" Newtonian except to say that you will be gathering a significantly greater amount of light with the larger unit. I have used my 'scope to view the planets and, while one is spared the scourge of chromatic aberration, I doubt that I see as clear an image as would someone with a decent quality refractor.

Eyepieces: You will probably find that the retailer from which you purchase a 'Dob' will also include eyepieces in the package. In my case it was 9mm, 15mm and 26mm. These are a pretty good starting point for someone like myself who hasn't used a 'light bucket' before. Keep in mind that the current GSO 10" Newts are around the f:5 mark. This means that collimation and regular checking of same is important. Should you buy such a beast then make sure you also purchase a collimating tool (I have found the Cheshire style of unit the best for my purposes). You will find plenty of information on this site on the subject.

Whatever you decide, Mystikal, I wish you well.

[Deeno]

Hey Mystikal

I purchased a 10” GSO DOB from Andrews just before Christmas. Being my first scope I can’t really compare performance to anything other than my trusty old 10x50 binocs. It did fit comfortably in the Corolla hatchback with plenty of room to spare for a trip down to the Hawksberry River, where it spent a week on a jetty before and after New Year. Views of Saturn wear amazing through the 6mm (it also came with 9mm, 15mm and 25mm) eyepiece with the Cassini Division clearly defined with at least 5 of its moons. Probably the least bright object I positively identified with my untrained eye, was the galaxy M77. I’ve only just caught up on sleep thanks to unfavorable conditions of the last week or so.
Nine days to Lockstock and counting!

[Mr. Subatomic]

Hey Mystikal,

As cool as GoTo systems are (I mean they're like your own personal robot, who wouldn't want that!), you'll always become more experienced through good old fashion starhopping with star maps. If you have the money for a GoTo it would be great, but don't rely on them too much and make sure you know what the telescope swivels around to look at. :)

[Gargoyle_Steve]

Hi Mystikal .... I have owned and used both the 10" GSO dob from Andrew's and the ETX-70. I can tell you there is no comparison whatsoever between the views. The much larger light gathering ability of the 10" reflector, plus the fact that is has a focal length of 1250mm compared to only 350mm for the ETX-70 means that you not only get everything much brighter and better defined in the 10" but you get more magnification as well.

Quick lesson : telescope focal length divided by eyepiece focal length = magnification.

Both scopes came with a 9mmm ep so I'll use that example.

The 10" gives a magnification of 1250/9 = 139x magnification (approx)
The ETX70 gives 350/9 = 39x approx.

Also, the 10" has approximately 47,000 mm2 of photon gathering capability (allowing for loss due to obstruction by secondary mirror) compared to roughly 3850 for the ETX. You would gather more than 12 times the amount of light in the dob than in the Meade.

Why did I own both? Several reasons, but if you still have the ETX then get a green laser pointer and rig a little bracket so you can attach it to the ETX and have it pointing exactly where the ETX is looking. Then use the ETX goto function as a comparitively inexpensive pushto guide for the bigger scope: let the ETX find your desired target, follow the beam with the 10" and there you have it.
:thumbsup:
Of course an Argo Navis guidance computer for the reflector is MUCH better ... but if you still have the ETX that's a cheap way to go.

Have fun, enjoy the free spectacle that nature provides.

Steve

[Karls48]

Hi Mystical

I don’t want to sway you one way or other but I have a GS-500 for about three years now and I must say it is quite good scope for $399. SV-1 mount is just another EQ5 and can carry this scope (and camera and 8x50 finder) no problems. You can add to it RA drive for $149. It will work quite well with 2x Barlow giving you 1500mm focal length at F8. When properly aligned it will keep star in 25mm eyepiece FV all night. It will focus (just) with CCD security cameras such as GStar and with ToUCam. As far as tracking goes, it beats ETX- 105 hands down.
Recently I put SV-1 on pier so I don’t have to drift align it every time I use it. It tracks even better now.