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Hello Everyone! I'm the sales manager and one of the technicians for Focus Scientific.
Hearing about Sky-Watcher's computerized Dobsonian, a lot of questions came up, and what good are questions without answers? It was time to dissect and field-test the scope. I chose the 10" Dobsonian, as it is at the top end of what is portable for me.
- Optics -
The scope was stored indoors at 22° C, and it was 7-10° C outside on May 16, 2010. Cool-down time was over an hour, which was expected. Swirling air could be seen in the extra-focular star pattern, even at the end of the session (1.5 hours). A fan would definitely reduce the cool-down time, or more smartly, putting the scope out before sitting down for dinner.
The optics produced crisp views of Saturn, and gave some of the best views of M13 under Barrhaven skies.
I then looked at:
M57 - made me want to blow smoke rings. Clearly visible with 25mm, a little less visible with the 10mm, but definitely could pick it out.
M81 and M82 - No problem. While M81 is technically brighter, M82 is more edge-on, and was more easily seen.
M87 - I first thought it was a globular cluster, until I looked it up. It is a face-on galaxy. I could detect it, but that was about it. If I was hunting Messiers manually, I would have easily missed this one. This would appear better in darker skies for sure.
- Mechanics -
There was very little backlash in the drives.
Micro-slewing left, right, up and down was smooth, with virtually zero lag when switching directions.
Speed 4 is best for centering objects, with no over-run and lower latency. Speed 5 is very touchy, and easily blows past the object, plus having higher latency (slower to react to button press/depress).
Large metal worm gear assemblies, and high-resolution encoders make for a solid, and reasonably accurate system.
The motor drives and encoders are set up as a closed-loop system, meaning the computer is able to keep track of the telescope's position, even if you move it manually. It's a full automatic goto system, but you could also push it most of the way into position, and let the computer take over. I'd like to see this feature built into their computerized equatorial mounts.
- Alignment -
I tested the unit unleveled, then almost leveled. Pointing accuracy increased a bit, so it's good advice to level the scope. I couldn't get the scope perfectly level - building a simple tilt-platform add-on would help.
Straight forward alignment. I chose "Brightest Star".
The scope asked me to slew to Saturn, and center it.
It then slewed to Arcturus, and asked me to center it.
Finally it slewed to Vega, and asked me to center it.
I was able to get all 3 objects to return within the field of view of the 25mm eyepiece (1 degree). Not bad considering the weight of the instrument, the size of the gearing, and the lack of perfect level.
- Misc -
I found the unit louder than I would have liked, and this is where it lost a point. I kept looking over my shoulder to see if anyone was watching. If you plan to observe in close quarters to a neighbours window in the summer, you might want to choose a quieter telescope. If you're familiar with the 90's vintage LX200 from Meade, they are similar in volume.
I like being able to change the volume of the beep, how the keypad LED's fade out, and how the keypad and LCD LED brightness can be controlled individually.
- Conclusion -
This scope is a lot of fun, and easy to use. It easily fit in my two door Civic. It worked fairly well, and I think Sky-Watcher has pushed the mass-produced Dobsonian to new heights.
Rating:  [4 of 5 Stars!] |
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