Choice of first scope

[ving (David)]

also a GS dob owner i can recommend them. I have had my 8" since early 2004 and it has zero rust, and all movements are smooth and easy. the altitude bearing has 2 springs for tention. I use 1 spring most of the time and change to 2 springs when carrying a heavy weight. never overbalances and never sticky. I have done no mods what so ever to the altitude. as for azimuth, you can do a zero cost mod (milk bottle washers) or get some ez-sliders or other furniture sliders to help...

optically my GS 8" is great for my needs. I have seen more detail in my 8" f/6 than i ever thought i would

[janoskiss (Steve H)]

Nightshift, I appreciate everything you are saying, as these GS (and I'm sure Synta too) Dobs are a cost/quality compromise. Also, it sounds like you got especially unlucky with the OTA (probably had a bit of surface rust before it was painted). But the optics is very capable and the scopes are usable out of the box, and can be made even better with a few tweaks. As far as I know there is nothing better available until you start looking at the Obsession style Dobs which cost around $5000+ for a 12.5".

The smartest thing Anthony at Bintel Melbourne said to me was that if you want a no compromise Dob, you build it yourself, because every off-the-shelf big scope is going to have its problems that will need user-tweaking. Failing that, get someone else (like that truss scope guy in North Vic, I forget his name) to custom build one for $$$.

[barees63]

FWIW, My 10" GSO Dob also has the rust problems as I may have mentioned a few times here but I suspect this may have more of a bad batch than a standard feature.. as far as the mount is concerned I haven't noticed any issue with water absorbtion or general build quality, I haven't done any mods to either Alt or Az (mine came with the teflon pads I believe earlier models may have had a dodgy roller bearing for the Az) and although the movement may not be "silky smooth" I find it perfectly useable.. The vast majority of comments I have read about GSO mirror quality are positive, especially for the money.. I certainly enjoy the views thru mine and suspect you would have to be a real expert to find much fault.. certainly not a problem for a first scope. The only things I would suggest is to buy it from a dealer who will center-spot the primary and demonstrate collimation for you - this will greatly enhance your initial enjoyment of the scope and maybe ask them whether they will offer some kind of rust guarantee? All things considered you won't go wrong with a GSO dob..

Bruce

[mickoking]

My GS Dob is fine. I reccomend them without hesitation.

There you have it, two opposing opinions, if I had $1000 to spend again on a DOB it sure would not be a GSO, I got a scope I reckon should have sold for no more than $500.00. I am happy to say "I told you so" though.

[janoskiss (Steve H)]

So what scope would you buy with a $1000 if not a GS Dob? Synta Dob? DIY Dob?

[cjmarsh81]

10" Skywatcher Dob. Got mine for $750. Love it. Still has a chipboard base (I haven't seen one that doesn't). I have read reviews on the internet that all say rust is a problem with a GSO. Have not read any about the skywatcher or saxon (they are the same with different badges.)

[ausastronomer (John Bambury)]

Rust is only a problem on a limited run of GSO dobs. The silver ones which were not properly painted with metal primer before hte silver was applied. My GSO dob is one of the early ones, it is black, it is over 5 yrs old, it has been rained upon, dewed upon, spat at and it does not have 1 spot of rust on the scope anywhere. In addition both mirrors still have the original coatings and the scope still supplies superb views.

I sympathise with those people that have the silver scopes that do have rust issues. That's also easily fixed by the way with 2 hours work and $30 worth of metal primer and spray enamel. No you shouldn't have to repaint the scope but its not a major issue and as far as I am aware the issue has now been resolved.

CS-John B

[yagon]

thanks for all the great feedback - i plan to place an order for a 80ED today.

Can anyone recommend some eyepieces to go with it?

I am thinking:
42mm
8mm
2x barlow

this would give me magnifications of: 14, 29, 75 and 150

[janoskiss (Steve H)]

Nice buy! You can't go wrong with the ED80.

42mm Superview might be good for very wide true field. Don't buy anything cheaper than this at this focal length. Don't expect it to work in a barlow, but maybe (30mm does). Long barrel version might have trouble reaching focus.

Assuming you cannot afford Pentaxes, Panoptics, and Naglers, but want wide FOV, I'd go with:

21mm and 13mm Stratus (or Hyperion) for clusters and largish DSOs.
8mm Stratus (or Hyperion) for mid-high mag.
Good 2" 2x barlow for more power and versatility.
Quirk with Stratus: you need a diag and barlow with no compression ring (just locking screws), otherwise you'll need to use them in 1.25" mode.
Downside of this package is weight.
If you are still power-hungry (scope can do 240x comfortably though 200x is probably the highest useful mag), a cheap way to get there is with a 2-3" barrel extender in the 2" barlow.

The shorter FL Superviews might work too, and they are cheap. But I'd be wary. Try and try again before you buy.

HD orthos worked well for me in this scope too, but they are not newbie/public friendly. "Can't see anything" is the typical response. Stratus is much easier to look through.

[yagon]

hmmm ... i'm not sure i know enough about eyepieces to be educated on which to buy

what is stratus - a brand or a design?

[janoskiss (Steve H)]

Orion Stratus. You can get them from the States, or hopefully through Bintel soon for $180 a pop. Baader Hyperion is a very similar eyepiece (EP), you can get them from OS for under $200 (locally for $265 from York, but maybe you can haggle).

Sorry, I kind of forgot this is your first scope (despite the title of the thread screaming out first scope ) and thought I'd just throw in what I personally think would be the best value and most versatile set.

What sort of mount are you putting the scope on? How much are you willing to spend on EPs?

[yagon]

OK, here are my thoughts on what I'll buy:

Saxon/Skywatcher 80ED refractor $549
AZ2 mount $199
90deg 2" x 2" erecting diagonal $99
Finderscope 8x50 90deg $99
TOTAL ~$950

All the above prices are based on the Andrew's website and ads.

So I'd like to spend about $300 or $400 on EPs, barlows, filters, and the other bits and pieces that I'll need. However, in the spirit of keeping it a simple as possible, I'd like to keep the number of EPs to 3 or maybe 4, including a barlow. I'd like to have a wide field view, as well as be able to take the scope up to at least 150x.

What are your thoughts on what I should get?

[yagon]

PS could this scope really get to 200x?

[ving (David)]

Originally Posted by ausastronomer

Rust is only a problem on a limited run of GSO dobs. The silver ones which were not properly painted with metal primer before hte silver was applied. CS-John B

mine is silver bought in 2004 and has none, so it seems its a run within the silver run that has the problem...

ED80! sounds like you will have a great scope sir!

[janoskiss (Steve H)]

Yagon, I'd recommend you go with AOE for all the accessories (and maybe the scope too). Going by the prices you have quoted, it will save you quite a few $ and the AOE guys are very helpful and seem knowledgeable about astronomy gear. So that leaves you with $400-$450 for EPs. Hmm not sure... Better call in the experts. aus John?

btw, the mount you want is AZ3 not AZ2. $179 last time I checked.

and yes 200x no probs.

[Striker (Tony)]

Not being much of a visual observer atm....but I do have an ED80....for most visuals the eyepieces I would be looking at around the 6-10mm you will use most of the time....giving you a magnification of 60 -100X.

Anyhing smaller then a 6mm you may find uncomfortable eye relief unless you go for the Barlowed Eyepieces for example like the Naglers Pentax or Meade UW and others.

[yagon]

Thanks for the feedback. Are there any other accessories that I should get at this stage, such as filters?

[ving (David)]

wouldnt worry bout filters...3 EPs and a barlow should do ya

.... oh and sky maps, red light, chair, etc.

[yagon]

I have just send an order via email to AOE - I can't wait to get it!

Thanks for everyone's assistance.