I think you're worth a double serving of happiness!Tal-200K (#199) with JMI NGF-Mini2M focuser on GEM3 • Astro-Tech AT80ED • Orion Sirius EQ-G with wireless EQDIRECT • Astro-Tech Voyager • Celestron Regal LX 10x42 • Helios 15x70 ATM projects: 14" f/5 truss Dobson: first light Jul 1, 2011 - currently in 'tweak & widget' mode
Show me an aging Greek and I'll show you the Nick of time.
Quote: Readers of this review may feel that I've been unduly negative.
"I have been paddling in the shallows of a great ocean of knowledge." - Sir Isaac Newton * * 15" F4.55 Starsplitter Dob & a Denk II binoviewer * * http://peaceofsky.wordpress.com/ Pacheco State Park Fremont Peak
Quote:Hi Cathy-At the end of your review you stated: Quote: Readers of this review may feel that I've been unduly negative. Maybe because i'm more that "old hand" you'd mentioned earlier, i didn't find the review to be negative at all... seems to me the primary glitch in the whole deal was the lack of clear instructions.Overall it seemed to me your review was very frank & straight-forward, and as such was a good PSA (public service announcement) to the Dob-buying community.
Quote:And congrats on your recent move- you've managed to land in a very beautiful area of the state! Are there darker skies east of you, out 580 & up Altamont? Where do the local astro-types & clubs go to view, locally? mike b
Teeter 8-inch STS #1
12mm Nagler T4
20mm Televue Plossl
22mm Nagler T4
32mm Televue Plossl
36mm Baader Hyperion
Never underestimate a good four-inch refractor.
Quote:Cathy,I also found that neither the Alt nor Az bearings could be sufficiently tightened to hold the scope steady in a 5kt wind.Peter
Dee space-scientist student violinist Nexstar8i,SV80S,80/9D,FC100,94 Brandon,TMB92SS,GM8 8" f/7 Discovery,12.5" Portaball, PST
Quote:I just found this thread, and the superb review by Cathy James of the Z10....Hi Cathy, I just happened across your excellent 1/19/11 review of your Z10. Wow, having bought the identical telescope last summer in 2012 (under the name Apertura,and called the A10),every word of your review reflects my own experiences exactly. Thanks for writing it. I had the same sinking feeling you describe so well when looking through a Cheshire! What a mess of non-concentric confusion. No one in the local astronomy club could figure it out either, and these guys are all into telescope making and optics. I gave up trying to sort it out, concluding that the secondary may not be set precisely in the center of the tube, or maybe it is not in a precise 90 degree relationship to the axis of the focuser. I wasn't sure if the focuser was even set at a 90 degree angle to the tube's geometric axis. Then I thought, well maybe the geometric axis is different from the optical axis of the primary...which would make the problem even more complicated.My brain shorted out at that point, and I just did the 'collimation' with the laser included with the scope, according to the simplistic instructions included in the very sketchy user's manual, and some comments made by the people who sold me the telescope when I called them for help. Now, despite this ongoing nonconcentricity of the profiles of the mirrors as seen through the Cheshire, when I just collimate with the simple red dot procedure, and get it really precise, the telescope performs quite well optically, at least on axis, though I wonder if it could be even better if the job were done 'right' by eliminating subtle angular distortions in the mechanical alignments of the telescope tube that must surely result in off-axis optical distortions of the light cone, such that while the red dot might well be lined up, the surrounding light cones are somewhat askew, leading to coma, astigmatism etc just beyond the center of the FOV. As an anecdotal example, last winter I could see the E and F stars in the Trapezium on nights when other, bigger and more expensive telescopes failed. That seems so unlikely if the wonky alignments of the tube components really impact performance significantly, don't you think? So I'm wondering if you have learned any more about this issue of collimation, how important is it, and why does the Cheshire differ from the laser collimator and which one should we believe. Thanks...and clear skies to you AngieSanta Barbara