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Posted by David Mottershead at 14:41 on 2010 Jul 30
HelloI have just purchased the Skywatcher Startravel 120mm achromatic short tube refractor, mounted on an EQ3-2 mount. I have a requirement for a non GOTO telescope as I use my scopes (well, weather permitting!!), at camping/caravanning sites, and although not really that loud, the whine of the GOTO motors on the Meades when slewing to a target has proved to be a bit of a nuisance on occasions, hence this purchase. I ordered the scope on Monday, 26 July, and it arrived the following morning thanks to a very prompt and courteous service by Harrison Telescopes ( http://www.harrisontelescopes.co.uk/ ). As an aside, at £299.99 delivered, Harrisons was the best price that I could find anywhere for this scope – and not having deep pockets this scope suited both my requirements and budget. The specification for this scope is:Objective Lens Diameter: 120mm Telescope Focal Length: 600mm (f/5) Eyepieces Supplied (1.25"): 10mm & 25mm x2 Deluxe Barlow Lens 1.25" (with camera adaptor)Magnifications (with optics supplied): x24, x48, x60, x120 Highest Practical Power (Potential): x240 Direct SLR Camera Connection Red Dot Finder Dual-Fit 1.25"/2" Focuser 1.25"/31.7mm Star Diagonal Multi-Coated Objective Lens EQ3-2 Deluxe Equatorial Mount Built-in Polar Alignment Scope Holder Aluminium Tripod with Accessory TrayThe scope came very well packed. Setup was quick and easy, although having had some years ago an 8" reflecting scope on an EQ3-2 mount (reviewed here http://www.dmottershead.co.uk/page5.html ) I was familiar with the mount, its assembly and workings. That said, using the supplied instruction manual, I would guess that most people could have the entire unit setup with 20 minutes or so of unpacking it. First impressions were favourable, with the scope and mount looking and feeling solid and competent. The scope sports the new Skywatcher black and white colourings, and the equatorial head is now also in white. The new colour scheme and solid quality of the unit gives the appearance and impression of a much more expensive item. I carried out some daylight testing of the optics and aligned the red dot finder unit. Everything so far was good.Then a miracle happened! On Tuesday evening, the same day the scope arrived, the skies completely cleared. A new scope and first light on the very day it arrived! The scope was already on the EQ3-2, so I simply picked up the assembled unit, (it weighs in at around 20Kgs, so with care can be moved around), and took it outside to cool down. While cooling down to the outside temperature, I set the mount to my latitude and approximately polar aligned it. The EQ3-2 has provision for a polar alignment scope, but this is an optional extra, so I simply looked through the section where the polar scope would sit until Polaris was centered through it – not a perfect alignment, but more than good enough for my visual session. I started by checking the collimation of the optics via star tests. The Airy ring patterns produced showed that the alignment of the optics was more or less perfect. Using the supplied 10 and 25mm modified achromat lenses, I then moved onto some double stars. All the stars came into focus as sharp pinpoints of light. Albireo (Beta Cygni) showed off its colours magnificently, and Mizars (Zeta Ursae Majoris) small, close 4th magnitude companion was easily split using the supplied 25mm lens (24x magnification), while obviously also showing Alcor. With the supplied 10mm lens (60x magnification) Mizar and its close companion had clear black sky between them. Epsilon Lyrae, the so called double double made a magnificent sight through the eyepiece.After taking in some beautiful, crisp wide field views of different areas of the sky, I moved across to the more or less full moon. Clearly a full, or just past full moon is not the best time for lunar observations, but a clear night is a rare night at the moment, so I wasnt about to miss the opportunity. Through both the 25 and 10mm lenses the moons detail was pinpoint sharp. More surprisingly, given this is a short tube F5 achromatic refractor, there was very little (but obviously some) of the expected chromatic aberration present. Inserting the supplied 2x Barlow, the views just got better. Along one limb craters, illuminated by the reflected sunlight, could be seen rising above the surface, silhouetted against the dark night sky. Again, even with higher magnification, virtually no chromatic aberration was discernable. I continued viewing the moon and stars using other, better quality lenses than the supplied ones. The optical performance didnt disappoint and with the better quality lenses, it really showed that the Skywatcher was indeed a very well made and put together scope. That isnt to say that the supplied modified achromat lenses (which I as I understand it are essentially Kellners) were bad they werent, and far from it simply that the other lenses allowed the true quality of the scopes optics to come through. Using the supplied lenses, I would estimate that the view was sharp across around 75 80% of the field view, and acceptable out to around 85%. There was, at the outer edges of the view some small distortion a very credible performance for a budget priced achromatic scope.The EQ3-2 mount proved to be solid base for the scope, easy to set up and use. Tapping one of the tripod legs produced vibrations in the scope, but these damped down within a second or so. I have to say that going back to my astronomical roots as it were, that is using manual controls, star hopping and setting circles, was far more enjoyable than letting one of my GOTO equipped scopes do it all for me. The GOTOs definitely have their place and use, but going back to the basics was just simply wonderful and manual setup and acquisition of the first target was much quicker and easier than with the GOTO!This was only one nights viewing, but based on this I would conclude that the Skywatcher Startravel 120 on the EQ3-2 performs at a level far higher than its price tag suggests, is well made, solid and represents excellent value for money. The only extra that I will get is an RA drive unit to allow objects to be tracked once aquired, and remain in the eyepiece without having to keep turning the manual control rod. As these types of drive are silent, no issues when out and about with it!
Posted by David Arditti at 13:50 on 2010 Jul 31
Thanks for the thorough review, David. I completely agree with you on the enjoyment value of going "back to basics" with a very simple, but well-made, telescope occasionally, when you are used to the more high-tech stuff, and dusting-off those traditional object locating skills. I hope you get many more nights of great observing out of it.
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