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Sorry for another question about my GEM.


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Hello everyone. I've posted here a few times recently about equatorial mounts. As skies are clear around here finally, I tried them out in the field. So I polar aligned and everything. I went and spotted the star Dubhe, so far so good; the RA and Dec matched my card. Here's where things went wrong. I had the coordinates of Deneb to find next. I spun the telescope until the pointers matched the RA and Dec. The telescope ended up pretty much upside down, at an impossible angle that was not pointed at Deneb (it was at the ground, actually). Can anyone think of what I did wrong and how I can fix it? Thanks

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I wonder if you have done nothing overly wrong, even if the worms were laughing merrily at what you were doing.

An equitorial mount has a "meridian flip" and I wonder if you have in effect managed to rotate the scope without performing the flip as you pass the meridian, or performed one when you shouldn't have. Never used mine enough to be able to answer with confidence and I cannot picture the process in my mind, it doesn't work too well until coffee No3 (on No1).

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The RA setting circle has two sets of numbers on it,  one for the Northern hemisphere and the other for the Southern hemisphere. The DEC axis also has two ranges for North and South. I suspect that you used the wrong set of numbers on the setting circles http://www.skyatnightmagazine.com/feature/how-guide/how-tomaster-setting-circles

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I think one of the above solutions would solve the problem. I tend to ignore my setting circles, and just use the polar scope to align the mount, and then use really only use the RA motor to keep targets in view. To move to another object I just release the clutches and move to the right area of sky, and then engage the clutches and star-hop using RA and DEC motors and the finder scope

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Yes, the RA scale has two sets of numbers, one for the southern hemisphere and one for the northern hemisphere.  For us in the northern hemisphere you would use the scale that the numbers increase as you move the RA to the east.  I use the top RA scale on my Orion Astroview mount.  Secondly, I would find objects that are close to the calibration star.  For example, M11, the Wild Duck cluster as well as others, is hard for me to star hop from my light polluted backyard.  Therefore, I centered the scope on Altair and dialed in Altair's RA and DA.  Then I move the scope to the RA and DA of M11.   There is was towards the edge of the field of view of my 25mm eyepeice I was using at the time.  This is also how found M3 using Arcturus in Bootes.  I then calibrated the RA and DA with M3's coordinates and then dialed in coordinates for M51 and found it.  Sometimes the object will be outside of the field of view.  I would then move the mount in the RA and it appears.

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