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Old 25-10-2008, 11:24 AM
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Starkler (Geoff)
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Join Date: Sep 2004
Location: Melbourne
Posts: 4,900
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 . Hopefully the Skywatcher proves to be a bit more durable over time.

It looks better than the lightbridge 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 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 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.

Last edited by Starkler; 25-10-2008 at 12:21 PM.
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