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Equatorial mount near the equator?

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#1 Philbl

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Posted 25 April 2009 - 12:07 AM

Hello all,

I'm new here so thanks in advance for any help you can offer and apologies if this question has already been asked (and answered)...

This is directed at all you folk that are using GOTO EQ mounts. I'm living at around 5 deg north and from my normal viewing location am unable to sight the NCP (trees/buildings.) I fancy moving back to an EQ mount (I'm currently using a Meade ALT/AZ ETX) and need to know if it's possible to polar align an EQ mount with a GOTO computer without being able to sight the NCP.

Can I just set my latitude, point north and tell the computer the time/date and let it do the hard work?

Hope it's not a daft question and thanks again.

Phil

#2 waassaabee

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Posted 25 April 2009 - 07:50 AM

For visual that may be close enough... Celestron's new AllStar alignment procedure would let you Polar Align on any star in the sky!! This procedure is available on any NexStar hand controller with v4.15. (CG5, CGEM and CGE/Pro) This would put your Goto's in the center and a polar alignment good enough for imaging.

#3 Eddgie

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Posted 25 April 2009 - 08:59 AM

Be aware of this. When used very close to the equator, it is possible that the counterweights will not clear the tripod. You may have to relocate the azimuth lug on the tripod mounting base so that the lug is between two legs (normally they are set up with the lug over the "North" leg). I don't know if this is the case with newer CG5s, but it was the case with older ones when used with heavier scopes.

It is not necessary to see the NCP to get a Go-To alignment. Simply use a compass (look up your magnetic deviation on a chart) and make that adjustment. Use a level and use the lattitude scale to adjust for your lattitude.

Your initial pointing might be off, however that is what the computer's in Go-to Scopes do... The allow you get good go-tos without being accuratly polar aligned (of course you will still get DRIFT, so will still need to do drift alignment or something).

Good luck.

#4 Philbl

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Posted 25 April 2009 - 11:18 PM

Thank you both.

Phil

#5 groz

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Posted 26 April 2009 - 01:51 AM

Be aware of this. When used very close to the equator, it is possible that the counterweights will not clear the tripod. You may have to relocate the azimuth lug on the tripod mounting base so that the lug is between two legs (normally they are set up with the lug over the "North" leg). I don't know if this is the case with newer CG5s, but it was the case with older ones when used with heavier scopes.


This is the case with our heq5, but the eq6-pro (atlas) has a 'south facing leg'. Even so, at 5 deg north, the counterweights will still hit the tripod legs. Easily cured, put it on a pedestal instead of a tripod.

The synscan hand controller that came with it doesn't have the 'all star' type of polar alignment routines (yet), but even without it, once one learns the process, getting accurately polar aligned with a drift align process is easily manageable.






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