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Has anyone in the group have experience using the new digital Dobs by Orion?
How do they compare to similar versions of Celestron and Meades GOTO models? TIA |
#2
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Steve wrote:
Has anyone in the group have experience using the new digital Dobs by Orion? How do they compare to similar versions of Celestron and Meades GOTO models? The GOTO scopes are motorized. The Dobs just have digitized setting circles and are "PUSHTO" designs. the DSCs tell you when you have pushed to the right orientation. The GOTO scopes track. The Dobs do not (no "whining" motors). The similarities with the LX-200 and NexStar lines are pretty limited. IMHO Orion's advertizing in the catalog is a bit misleading to a beginner. Phil |
#3
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Has anyone in the group have experience using the new digital Dobs by Orion?
How do they compare to similar versions of Celestron and Meades GOTO models? TIA Which scopes are you comparing them to? The GOTO SCTs? The Newtonians of various types that Meade and Celestron sell? jon |
#4
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"Steve" wrote in message
.net... Has anyone in the group have experience using the new digital Dobs by Orion? How do they compare to similar versions of Celestron and Meades GOTO models? Comparing a Celestron 8" SCT with Starbright, to an XT10 Skyquest from Orion (the older Guan Sheng model). The 10" is brighter, provides better resolution, and has better response to low contrast details on Mars and Jupiter. That said, the difference in each case is really marginal, and more dependent on atmospheric conditions than scope specs and design. When atmospheric conditions are good for observing, both scopes perform admirably. The one place where I've seen the XT10 provide an appreciable improvement, is in drawing out spiral structure in M51 under my local conditions, as well as allowing easier detection of other objects with low surface brightness (such as M101). But that's simply a result that a 10" aperture of any other design would also provide. Based on the comparison of these two scopes, I would venture a reasonable guess that a 10" SCT would outperform an 8" F6 Newtonian in brightness and contrast, and that an 11" SCT would beat a 10" Newt in brightness and contrast, by a nose. (I'm not promoting one over the other on optics, btw. As far as I'm concerned, the choice between an SCT and a Newt or Dob of similar aperture should be made on a combination of things including mount, portability and versatility. Buying an 8" Newt OTA strictly to outperform an 8" SCT optically is, IMO, unreasonable considering the minimal differences.) That said, you _will_ need a little more aperture in the SCT, to compensate for the loss of light on each surface, and to make up for the larger CO. But again, we're really splitting hairs. As for the difference between a GoTo and DSCs, I prefer DSCs and an EQ mounting. They are virtually noiseless, and for visual use provide every bit the needed accuracy. Add an EQ Platform to a Dob, use a GEM for a Newt or SCT, or a Fork/Wedge for an SCT, and you have all the function of a GoTo. There's really only one place where the GoTo is of unquestionable value to the visual astronomer (although being this is saa, someone will no doubt object), and that's with an altazimuth fork or Dob mount, since motorized tracking is then possible. If you are seriously considering the Dob, buy it because you want a Dob, not because of any techno gadgets that apply. You will still have to hand-track using the Dob with DSCs, and tracking is a much larger issue than finding, IMO. IOW, based on my current exeperiences with Dobs, Forks, Wedges and GEMs, given the choice between a Dob with DSCs and a Dob with EQ platform. I'd definitely go for the one with platform drive. Finding stuff is a pain, but no where near as much a pain as hand tracking easy to find targets above some threshold of magnification (in my case, I get annoyed above 150x). Lastly, with the platform drive, you don't lose your position if you need to spend time studying the charts during a star hop. That makes star hopping less of a pain, thus the DSCs less of an advantage. Stephen Paul |
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Stephen,
Good comments. I differ though on the toss up between tracking and DSCs (I have neither at the moment), but I'm more into DSOs, where the mag is lowish and the objects often faint and hard to find (I find!). DSCs don't preclude the fun/frustration of star hopping, but would at least be a handy confirmation of where you've landed. For planets and public viewings, EQ... Mark IOW, based on my current exeperiences with Dobs, Forks, Wedges and GEMs, given the choice between a Dob with DSCs and a Dob with EQ platform. I'd definitely go for the one with platform drive. Finding stuff is a pain, but no where near as much a pain as hand tracking easy to find targets above some threshold of magnification (in my case, I get annoyed above 150x). Lastly, with the platform drive, you don't lose your position if you need to spend time studying the charts during a star hop. That makes star hopping less of a pain, thus the DSCs less of an advantage. Stephen Paul |
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