12 inch Dobs - Feedback on brands

[Smyths77 (Stuart)]

Hi all,

I'm looking at purchasing a 12 inch Dob and would value feedback on the quality of the optics in say the Meade 12 inch Lightbridge v's the Saxon/Skywatcher solid and flexitube designs. I've read the Meade has very good optics from one magazine but know that there can be variance in optical quality.

I would be interested in which has the sharpest optics. Keen to hear from people who have observed through a variety of these.

Stuart

[mbaddah (Mo)]

Hi Stuart,

There are many variables which you would need to consider when deciding which 12" dob to purchase:

- Will you be transporting it to dark sky or keeping it in the house? If transporting, a truss is most convenient, else solid tube is fine.
- All optics supplied in those scopes come from China. Meade use BK7 glass while Skywatcher uses Pyrex.
- Skywatcher uses straight pole setup (handy for bringing items to focus like camera/binoviewers), the Lightbridge uses V-truss design (breaks up into more compact pieces).
- The skywatcher doesn't have a fan on the primary, the LB does. The LB also comes with a lightshroud now, the skywatcher doesn't. The LB also has bobs style knobs for collimation now, the skywatcher doesn't.
- The skywatcher has 3 (very small) teflon pads for the azimuth motion, the lightbridge has a lazy susan system. The skywatcher is too stiff, the LB is too smooth!
- The focuser on the lightbridge has a 10:1 crayford focuser. The skywatcher focus has a crayford style focuser, but it's not up to par as the lightbridge.

There are a few other minor things. I'd lean towards the lightbridge simply because it comes better equipped then the skywatcher. Optics are a gamble in either...

Hope this helps

[mbaddah (Mo)]

Also one other thing, the Skywatcher now has a GOTO line. If tracking and goto are important to you, then go for the skywatcher as the LB doesn't have anything similar in its line unless you add Argo/Servocat.

[vanwonky (Dave)]

Originally Posted by mbaddah

- The focuser on the lightbridge has a 10:1 crayford focuser. The skywatcher focus has a crayford style focuser, but it's not up to par as the lightbridge.

Is this right? "Come with ultra smooth Crayford focusers" seems to be quoted in the specs on the Skywatcher 12" collapsible I am looking at.

[astronut (John)]

I've had my 12" Lightbridge for 5 years. Out of the box it's a very good scope.
I've made mods to suit my observing style. I would buy it again , if I had my time over.

[Tiotion (Jack)]

Vanwonky, you'll never hear a manufacturer call their equipment "pretty decent, does what it's supposed to do". By this is mean it's all just marketing. None of the mass produced focusers will be as "ultra smooth" as 3rd party ones like the feather touch or moonlite. Your main concern here is whether or not it's 1:10 as this will be greater difference between their performance. Mbaddah has given you a pretty good run down of differences and IMO they all perform about the same and they'll all require some sort of modifications to get them running right.
Best bet is to see them in person, be it at a star party or in store. What ever you choose, you'll have a wonderful tool to start observing with for many many years and youll be gob smacked when you view your first DSO.
Clear skies
Jack
Ps... Good thing your in Perth. The rain will go your way when you get your scope and give us some clear skies finally! Thanks for that!

[vanwonky (Dave)]

OK 1:10 - understood. You just keep learning! Awesome.
Somebody must have bought a scope in Perth as we now do have rain!

[Tiotion (Jack)]

Don't forget, most retailers can swap the original Focuser for a dual speed one for a fee... Just to make your decision a bit harder lol.

[Screwdriverone (Chris)]

I have had a 12' collapsible Skywatcher and mine was excellent. The only reason I sold it was because I bought an 8' Black diamond on an Heq5 Pro for visual and AP.

If I had waited until the goto dobs had come out, I would have bought a goto 10-12" in a heartbeat....push/nudge got annoying after a while.

Love the nerd factor I get with a goto Gem connected to Stellarium.....tank commander.....FIRE!

Cheers

Chris

[Shiraz (Ray)]

Hi Stuart. FWIW, I have a GSO 12 Dob and have read that the Meade systems use the same mirrors. From star testing against the diagrams in Suiter's book, this particular mirror seems to be corrected to about 1/14 wave (surface), there is a slight turned edge and a little roughness (neither of which is particularly noticeable when viewing). Overall, it is good to look through, snaps into focus and runs out of steam on Saturn and the moon at about 500x if seeing allows. Hope this is useful. Regards Ray

[DJ N]

I picked up my 12 inch Skywatcher Goto dob a couple of weeks ago.... in a nutshell........ absolutely awesome. The strut arrangement makes transporting this scope so much easier than a solid tube. As for recollimating, very minor tweaks required......which would be the case with a solid tube anyway. As for the goto and tracking...... simply superb. Last night, I noticed there was a break in the cloud, so decided to do a quick second light. Total setup time was literally 5 minutes. I did a 2 star alignment on Alpha Centauri then Canopus and I was ready to go. I was more interested in tracking and goto checks last night rather than "the view". The goto was better than I would have hoped for. Some of the objects that I targetted were Omega centauri, Centaurus A, Eta, Tarantula, Tuc 47, NGC3918 to name a few and every object was within the inner 50% of the fov of my 24mm Panoptic ( I did not check to ensure the mount was 'level' on initial setup). I left the scope tracking on Eta, and when I came back 20 minutes later, it was still fairly central.

Absolutely love this scope. Only down side is that it is A LOT louder than my EQ6...... Absolutely hanging to get the scope to dark skies!!

[Stu Ward]

I can only concur with Daniels comments regarding the 12 Skywatcher goto. Fantastic bit of kit. So easy to collimate and setup.
I take mine apart to move as its just too heavy with the tube and the base.
I move mine about 20 meters from a room to my viewing area.
Total time for disassembly to reassembly and collimate is 10 mins.
Around half an hour to cool, longer if you want to get the best views.
5 mins max to align and you are good to go for the night.
My ground is not particularly level, so i have purchased a bubble level that i have attached to the front of the base $8 and a set of builders wedges $10 from Bunnings to level her up.
Cost me $2000 from Andrews and was definately my best purchase this year.
I see that the price at Andrews has increased by $200 now, but i would still buy.

Daniel is right though, the motors are noisy.

Stu