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Edge HD 8 fork mount

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#1 tomnjulie

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Posted 13 February 2013 - 04:17 AM

Took the edge out the other night to try and pick outma specific star to view an occultation. It seemed that murphys law kicked in and everything that could go wrong did. The dang thing would not get a succesful alignment. The gps did its part. We tried the solar system and two star. Eventually we got enough of an alignment to work. My question I want to ask is this. What factors will cause a goto to not find its alignment. Do certain stars not work well? Does it mess it up if you use planets and stars. If you use a fork mount please give me your tequnique to get the best and most reliable alignment. What eyepiece do you use while aligning? Help and suggestions are appreciated. Thanks.

#2 MikeBOKC

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Posted 13 February 2013 - 09:07 AM

You can use planets on the 3 star alignment but not on the two star. It is important to use two stars that are well separated in the sky. For example, I always start with Polaris as my first star (it holds still!) and then chose something in Orion this time of year, maybe Rigel or even Sirius. It is also vital to make sure the GPS is completely linked before beginning. Just because the HC shows the correct time does not mean the GPS has linked with all the necessary satellites. I usually use a reticle eyepiece, but you can do fine with careful centering in the 40mm eyepiece that comes with the scope. Finally, it helps to make final corrections before hitting the enter and align commands by moving the scope up and to the right. If necessary, start eith your target low and left and make those moves at slow slew speed before hitting the commands.

#3 A. Viegas

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Posted 13 February 2013 - 05:43 PM

Picking the best two alignment stars is actually important. So I suggest if you have an Iphone/Ipad/Itouch I would suggest this little app, written by a fellow CN'er... I have it and its worth the couple of $

Alt AZ Align

Also his free app for the weather "Sky Harbinger" is also highly recommended.

If you want to stay uber cheap, and have an old windows PC around, then you can download the classic "best pair" which basically does the same thing, albeit in a less tech easy way...

Best Pair

Good luck!
Al

P.S.

The successful alignment technique which is discussed in the manual is to center the first star, use a cross-hair reticle eyepiece if you have or if not use a higher power eyepiece, like a 8 or 9mm for instance. Remember to move the star to the center of the eyepiece in the last part of the alignment using the "UP" and "RIGHT" arrow buttons, each time.

#4 Bob Griffiths

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Posted 14 February 2013 - 11:39 AM

I too always use Polaris as my first star...then I pick a second star in the neighborhood of 90 degrees away BUT not higher in the sky then say 75 degrees not lower then 30 degrees...

works every time... as for what eyepiece I use..normally its the 30 mm POS I store as a dust shield in my diagonal...I do defocus the star when centering until it almost fills up the entire FOV

Bob G.






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