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Dave47tuc
25-10-2008, 10:16 AM
Greetings all,:)
I thought I would share my thoughts of my new Skywatcher 12” Flexi Dob. I have been observing for over 20 years.
After owning a few scopes, I had a 10” Dob and made the mistake of thinking smaller was better. For some maybe, but DSO just did not cut it in a small scope. So I decided I wanted a 12” scope.
Which to buy. Well it came down to 2. The Meade Lightbridge and the SW Flexi Dob.
I wanted a scope that would fit in the car and not be too much trouble setting up. So the SW won. After speaking to a few dealers here in Australia I was able to get a good price of Steve Massey of My Astro Shop. Highly recommended if you need astro gear.

When the scope arrived a few days ago, one really big box for the ota, then a smaller box for the mount. All very well packed. This is good as the boxes where damaged. But it was only superficial.
I put the mount together straight away. The tube was ready to go out of the box once unpacked.
I was pleasantly surprised on the fit and finish. Really nice. The paint work is white and black with gold fleck through it. Very nice indeed.
I have a small sedan car and the OTA fits on the back seat very easy, while the mount went in the front seat. One of the main reasons for getting this scope.

Now last night out under the stars. I use four eyepieces a 32mm Meade wide field. 17 mm Hyperion. 10 mm Pentax XW and my friends 7 mm Penats XL. I also have a Paraccor.

Put the mount on the ground then ota goes on, lift the top half of the ota (moves very smoothly) lock it into place take covers off then put the mount handles on and you’re ready to go. No more than a couple of minutes.
A bit on how it moved. This scope is out of the box with no mods. The Azimuth moves very smoothly but too easily, and will need to be slowed down a bit. Some bits of the Velcro will do. The material bit!
The Altitude is the part that was not very smooth. It was too stiff to move up and down smoothly. With the handles fully loose it was still to hard to move. The scope balanced very well but needed to move better. I will fix this over time. I had a GSO 10” which was the same and I fixed it. The ota has no fan so cooling was done as the temperature drops. I will put a fan on in the future.


Most people will wonder if the scope flexes with the Paraccor and eyepieces in it. I did not notice this in normal movements. The poles are steel and seem very strong. The focuser is a crayford but its no feather touch. It was serviceable and it took a few seconds for the image to stop shaking at high power. I’m not sure if I will change this in the future.
Collimation was very good out of the box the secondary was fine with minor tweaking of the main mirror.

Now first light was Venus then Jupiter. It was twilight and those objects where the only ones I could see. Seeing was poor and the mirror was not cooled. Obvious thing was they where bright in the eyepiece.

I spent about 4 hours observing with my friend Geoff and his 10” GSO. Without going into detail on every object observed. It was obvious that the 12” was showing images brighter that a 10”
Actually the SW was very nice indeed. With seeing average at best and transparency average again.

I used the Paraccor but really did not need it. The 10 XW did not come to focus. But Stars where sharp across the field with out the Paraccor anyway. The 32 wide field was better with the Paraccor but not that bad without it. Some seagulls at the last 3rd of the field.
I seemed to go from finding objects in the 32 mm then going to the 10mm for a closer look.
IMO the 10 mm Xw is the best eyepiece in the world!
47 Tucanae was just awesome in the XW .
When we looked at M2 and M15 and NGC 362. We did notice that the 12” was able to resolve the Globular better than the 10”
On some Galaxy’s in the 12” where always brighter in the 12”
When I looked at 253 in my old 6” then in Geoff’s 15” (which he has as well) some weeks ago I thought that’s it I need a big scope again.
The result was great. I’ now seeing DSO’s as I like them.
To have a bigger scope like a 15”or 18” would be great but it could not fit in the car and the budget (wife) will not allow it!

All in all at this stage I’m happy with the scope out of the box. I will make some small mods on the movements, but overall it seems a great scope for the money. Oh I did put a right angle correct image finder. Also I Rigel quick finder is on the shopping list.

And finally an Argo Navis as soon as funds (wife) allows.
I don’t see the need on getting more eyepieces as I will have the four and that’s ranges power form 50x to 250x I’m sure the XW will spend a lot of time in the focuser. I hope some who are considering this scope got something out of my report and first light with the SW 12” Flexi Dob.
Thanks for reading and sorry for any spelling mistakes.
Please feel free to ask any? You may have on the scope.

Clear skies.
David.:thumbsup:

Starkler
25-10-2008, 11:24 AM
I observed with Dave last night and I'll add my thoughts on this scope.

Those looking for maximum easily portable aperture will consider this scope or the Lightbridge. I like the Skywatcher.

All of the hardware of the Skywatcher is captive and without loose truss poles to attach and remove each time you want to transport it in the car. The Skywatcher collapses/extends merely by operating three screw clamps of solid construction. Nothing could be simpler. I have heard stories of the cast aluminium tabs on lightbridge UTA breaking and failing with the UTA falling onto the ground as a result :scared:. Hopefully the Skywatcher proves to be a bit more durable over time.

It looks better than the lightbridge :D The black metallic fleck paint finish looks great! I was concerned to see white painted end rings at first until discovering that on the inside where it matters, those parts are indeed painted flat black.

In use the scope appears to be nicely balanced, with a weight bias toward the back of the scope, allowing you to add some weight at the front end without fear of the scope taking a nose dive. The azimuth bearing is of a lazy susan type, which is much too free moving for my tastes and requires some added friction given that the altitude motion when fully loosened is still quite stiff by comparison. Some velcro or similar between the rocker box and ground board should fix that. What did annoy me a little was a tendency for the scope to wobble a bit when trying to achieve focus. Whether this is related to the lazy susan bearing or lack of stiffness on the tube assembly remains to be seen.

The optics given the average seeing appear to be great :D Out of the box this scope exhibited no signs of astigmatism or signs of over zealous mirror clamping issues. Star testing showed no signs of issues with rings of equal brightness on either side of focus, and no indication of turned edge. Of course very good seeing is required to fully evaluate optics, but from what I could see, this optics set looks like a winner :D We compared with my 10" gso dob that I bought about four years ago. The primary in my gso is slightly over corrected as shown in star tests. We both commented that we could see the difference at the eyepiece as the "seeing looking slightly better" in the Skywatcher. If this was temperature related the gso should have had a head start given it had a cooling fan running for about an hour beforehand and I turned it off after noting the temperature wasn't dropping much as it was a warmish night.

The secondary mirror is mounted on a stalk attached to the back of the mirror. This leaves the mirror fully exposed to the night air and on dewy nights, well this mirror is going to dew up, no two ways about it. The centre mounted stalk prevents the fitting of an Astrosystems style secondary heater, so some other solution would need to be considered. I believe the Lightbridge uses the standard plastic secondary holder as seen on gso scopes. It is possible to fit an Astrosystems secondary heater inside those. The flip side is that those plastic holders can be a source of astigmatism to the secondary mirror until sorted out.

If deciding between the Skywatcher and the Lightbridge, there may be one factor which decides for you, which is the height of the base.
The Skywatcher's base is taller as it covers the full height of the altitude bearings. It more or less only just made it being loaded into the front seat of Dave's car, a Mitsubishi Magna. If you own a smaller car or one with less than generous head room, it would pay to check on this before buying.

Finally the Lightbridge has serious competition, and given that in Australia the Skywatcher is cheaper, I'd say that Meade has some catching up to do.

Kevnool
25-10-2008, 11:28 AM
Good onya David for you new addition and good report and read.

I hope you have many clear observing nights with this 12" baby.

Remember aperature rules........cheers Kev.

Tilt
25-10-2008, 11:41 AM
Great report David.

The SW 12" Flexi Dob seems to be a very nice scope. The Argo Navis that you plan to fit at a later stage will really make this a fantastic set up.

Michael

§AB
25-10-2008, 01:46 PM
Nice report Dave, glad you are enjoying your new toy :thumbsup:

One suggesten re the azimuth motions:- try sticking blocks of foam between the ground board and the rocker box, I've heard it works well on lazy susan systems.

Starkler
26-10-2008, 02:02 PM
If this thread was about some new dinky little refractor it would be two pages long by now. :confuse3:

erick
26-10-2008, 02:09 PM
I only just saw it this morning and was interested given the premium one seems to pay for Skywatcher-named scopes. However the collapsible strut struck me as a very sensible approach when I first saw it mentioned in the press.

Most interesting was Dave's realisation that he cannot live with smaller aperture, regardless of quality! A salutory lesson?

Davekyn
26-10-2008, 02:23 PM
Nice One Dave,
I got the GSO Tube model...Oh Well...It sure was good to read about yours! I am glad more and more people are getting into Dobs...Although my new mission is to save for a astrophotgraphy gear (after I get a car)...I already have my sights set on a 16" Turss of some kind.

Thanks for the review!!!
47tuc rules as well...Nice view in a 12" Dob, that's for sure.

Dave

Starkler
26-10-2008, 03:47 PM
Actually the skywatcher in this form was available for $200 less than the competing Lightbridge before the $au went crazy. What prices are now you would have to check.



Indeed :lol:

I cant get excited by any small scope, regardless of optical quality. A small scope is still a small scope and what you can see with it is still limited by its size.
I sold my Vixen refractor after working this out for myself. The optics were great giving nice sharp stars and a contrasty view, but I just couldn't see enough of them (or of anything else) :sadeyes:

I think this format of portable 12" scopes is a winner for being the biggest easily car transportable scope. Quick and easy to setup, 5 min tops to setup , collimate and be ready to observe :)

Dave47tuc
26-10-2008, 04:21 PM
Some lessons are expensive to learn:rolleyes:

Each to there own re what scope to have.:D

First time out was great. If the other nights are as good it will be fun.
Now I have to save for one more EP and the AN.:)

Dave47tuc
27-10-2008, 11:47 AM
Something I did not mention is the weight.

The OTA may collapse but it’s still heavy. But being shorter it’s easier to handle.
The mount is also heavy, but I found the OTA heavier.
The mount was more awkward to put in the car, as it just fits in at an angle then covers the entire front seat and is quite high as well.

In all if you can not lift 15 kg easily then this scope may not be for you.
But it much easier to move and fit in a car than a full tube 12”

janoskiss
27-10-2008, 12:35 PM
Sounds like a great scope, Dave. Maybe I'll buy it off you in a couple weeks when it goes for sale on IceTrade. :P

till then, you enjoy! :D

Dave47tuc
27-10-2008, 03:06 PM
I have sore ribs with all the poking:poke:
My wife just's:rolleyes::rolleyes::rolleyes ::rolleyes::rolleyes::screwy:

Some of me never learns:help:

Amunous
23-06-2010, 01:38 PM
i have recently purchased this scope myself and i couldnt be happier with it.. i could have gone with a lightbridge but a scope that comes completely apart just didnt intrest me at this size. ill wait till i get a bigger ap for something like that.
as far as image and portability its tops i have no complaints..

and to fix the up down motion i copied the idea that this guy had..
http://www.spacealberta.com/equipment/dob12/dob12.htm#bearings
have alook at what he did with the alt bearings.. i got the bolts for about $4 and then bought a cheap skateboard $10 and swapped it all out.. smooth as now couldnt be more pleased with the result.

sejanus
23-06-2010, 01:54 PM
holy thread resurrection batman!