[Graeme Bluestar (Graeme)]

About eight months ago I took the plunge and purchased one of these new Dobson mounted reflectors with the optional GoTo mount. There does not appear to have been a great deal of discussion about them here on IIS, so I thought I would give a brief review of my experiences so far.
Firstly a summary of the items I consider to be less than satisfactory upon initial use/assembly of the scope:

Installed the finder scope & bracket into the mounting foot, and finger tightened the retaining screw. A few minutes it fell out of its own accord straight onto the eyepiece end, bending the housing. Installed again the same way, but found I needed to overtighten the screw with a multiwrench in order to hold the scope & bracket assembly securely. A right angle finder would be much better – I have since installed a Celestron RACI unit – a lot easier on the neck to use!

The Primary Mirror Assembly three adjuster locking knobs were of very poor quality – I replaced these straightway. Also the threads for these in the base were not properly formed – I tapped these out with a thread tap. The three adjuster screws/knobs could also probably be improved.

The wrap around light shroud had areas of faulty stitching – I had these re-stitched.

Poor quality eyepieces supplied with scope.

There are not enough counterweights supplied – even when operational with only all the supplied equipment an extra 3kg was needed to even come close to a balance.

Poor design of the counterweight attachment system – the single long bolt threaded straight into a thin cast area of the PMA base is probably not up to the job, especially if additional equipment/weight is fitted to the top end. I will be re-designing this setup in the future.

Many of the fasteners are already showing signs of corrosion – I will be replacing these with stainless steel ones where possible.

Poorly translated instruction manual, with poor quality assembly diagrams – some actual photos would be much better, especially the ones showing fitting of the drive cable assembly. The instructions for fitting the light shield need to be included in the manual in their proper sequence. With the present separate instruction sheet I went to fit it as the last job, only to find I had to go back and disassemble some parts in order to fit it.

The shield itself is of poor quality plastic – one day the telescope spent in the July winter sun and it deformed beyond repair.

It was good to see a cover for the secondary mirror included, but there is no way to secure it when the telescope is in a vertical position – fitting of a Velcro retaining strap has cured this.
The primary mirror cover will not fit around the telescope struts when assembled – trimming of the cover edge at the struts area was required. However, kudos to Skywatcher for this cover – it is a much better quality cover than the flimsy plastic one supplied with my 16” Lightbridge.

Inside the cover is a foam pad adhered to the cover. Upon unpacking the unit the foam was found to have detached and lying on the mirror surface – a better quality adhesive required.


And now the good stuff! –

Very well packaged – upon initial opening of the four boxes everything was found to be in pristine condition. For those who want to keep the scope as a transportable setup, enclosing the existing packaging in built to purpose plywood boxes or similar would provide excellent storage for long term use.

Using my Parkes GS 30mm eyepiece the star images are nice crisp points, with minimal coma around the edge, especially considering the F-ratio of the scope. A coma corrector may help here.
We tried a number of different good quality eyepieces with the scope, and kept coming back to the Parkes.

The GoTo system seems to work OK, and tracks quite OK for visual work at least – I could centre an object, leave it for 10 minutes and return to find it still well in the FOV. The Synscan hand controller & software is reasonably easy to operate – regular use and I expect to learn its procedures quite easily.

Spectacular views of deep sky objects including the Tarantula Nebula & associated LMC objects, M42 and The Trapezium, the Jewelbox open cluster, Eta Carinae & The Homonculus, as well as other Milky Way objects in this area. Sirius B was clearly resolved.

After a hot day here on Saturday the mirror design seemed to cool down quite effectively, by 8.00pm and true night we did not notice any problems that could be attributed to this. There appears to be provision on the PMA to fit some cooling fans (not included with the scope) if required in the future.

Please note I have only spent about 3 hours actually using the scope visually, so I am unable to give a fully detailed report of its capabilities at this time. However overall I am happy with it, as I believe this scope gives good value for money. A little time & $$ correcting its weak points as outlined above would be well spent. I fully agree with Skywatcher’s advice – it definitely requires two people to setup / pull down, one person would never do it. Sometime in the future I hope to install it in a permanent setup, its sheer size & bulk stretches the boundaries of portability I think!