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CG-5 from latitudes very close to equator??

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#1 David Rivas

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Posted 21 May 2009 - 11:44 AM

Hello everybody!
I was just told(I can't find info about it!!) that the CG-5 wouldn't have been designed for observation from the equator or near the equator... is this true?? I need to know if it can be adjusted to 12° 04' 56" which is Lima's latitude.
Have someone used the CG-5 from a similar latitude?? or even better, can someone please tell me if it can be certainly adjusted to my latitude?? this info is crucial to finally do the purchase!
Thanks!!!
David

#2 Pedestal

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Posted 21 May 2009 - 07:53 PM

At 29:47, my ASGT is as far down as it will go. If the tripod is leaning only a few degrees south, it will not work.
Hubert

#3 ibase

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Posted 21 May 2009 - 07:58 PM

Hi David,

It's 14* north of the equator here in Manila, Philippines and an astro buddy who has used the same mount for quite some time here advised me to just remove the front latitude adjustment screw on my newly acquired CG-5 GT and it worked fine. Hope this helps.

Best,

Hernando

#4 David Rivas

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Posted 21 May 2009 - 11:43 PM

Hi guys!
Thank you very much!!
Hernando, once more thank you!!
It seems I'd have to remove such a bolt too then...
Fortunately, it's possible!!! thanks a lot!!!!!!!!!!
Bests,

David

#5 rmollise

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Posted 22 May 2009 - 08:32 AM

At 29:47, my ASGT is as far down as it will go. If the tripod is leaning only a few degrees south, it will not work.
Hubert


Sure it will. All you have to do is remove the front latitude adjustment bolt, as somebody else mentioned. Heck, I had to do that at 30 degrees N.

#6 rmollise

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Posted 22 May 2009 - 08:34 AM

Hi guys!
Thank you very much!!
Hernando, once more thank you!!
It seems I'd have to remove such a bolt too then...
Fortunately, it's possible!!! thanks a lot!!!!!!!!!!
Bests,

David


Let me add that the front bolt isn't really needed. The weight of a telescope on the mount means it's easy to adjust up/down with just the rear bolt in place.

#7 Eddgie

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Posted 22 May 2009 - 11:02 AM

Also, depending on the position of the counterweight, it MIGHT contact the tripod leg.

These mounts USED to be made so that the post or azimuth adjustment could be removed from the bottom. There was a hole 180 degrees across from where the post is normally set when it is shipped.

Moving the post to the other hole positions the head so that the counterweight is BETWEEN two legs so that it can clear them (the leg that used to point north now points south.

Beware though that if you DO use the scope at higher lattitudes with a lot of weight out on the end of the shaft, it can tip over when you remove the scope.

Regards.

But moving the az adjusting post and re-orienting the head should get you to the equator.

#8 Pedestal

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Posted 22 May 2009 - 10:18 PM

At 29:47, my ASGT is as far down as it will go. If the tripod is leaning only a few degrees south, it will not work.
Hubert


Sure it will. All you have to do is remove the front latitude adjustment bolt, as somebody else mentioned. Heck, I had to do that at 30 degrees N.


That is with the bolt removed. The plastic housing prevents it from going lower.
Hubert

#9 rmollise

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Posted 23 May 2009 - 09:22 AM


That is with the bolt removed. The plastic housing prevents it from going lower.
Hubert


Well, yeah. You have to remove the front bolt. But it don't do pea turkey for you anyway.

#10 sfth13

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Posted 23 May 2009 - 12:16 PM

I had the same problem and this is what Celestron sent me:
Here is the information on adjusting the mount. The Advanced GT mount has two latitude adjustment screws that bear against the lowest part of the equatorial head, allowing fine adjustments in latitude. Unfortunately, they also limit the range in latitudes. Near-polar (circumpolar) latitudes and a wide band of tropical latitudes below 30 degrees are outside of this range.

Fortunately, there are workarounds to extend the capabilities of the mount so it can be used from more locations on the earth’s surface.

For tropical latitudes below 30 degrees, the RA motor cover will bump into the latitude thumbscrew and the tripod may interfere with the counterweight. Here are two things you can do.

Remove the plate that holds the latitude screw from the front side of the mount. Since it is on the same side as the counterweight, it is really not needed when the scope is in use, as equatorial head's weight is always resting on the back latitude screw. Taking the plate off allows the latitude of the head to be lowered to your location.

Now the counterweight may bump the tripod leg in the new, lowered position. To prevent this, take the equatorial mount head off the tripod, exposing the top of the tripod. You will see the square-shaped azimuth adjustment post. Unthread the post from its current position in line with the single tripod leg and move it to the threaded hole 180 degrees away located between the tripod legs. Reassemble the head to the tripod.

Caution: this rotation of the head on the tripod will shift the scope’s center of gravity, increasing the likelihood of toppling the mount. Tying or weighting of the opposing tripod leg is recommended in this situation.

For high, near polar latitudes, there is no removal of parts that will allow adjustments like those for tropical latitudes. Here your only recourse is to tilt back the tripod by shortening-lengthening the legs to increase the inclination of the polar axis. Again, caution is advised, as this will shift the scope’s center of gravity. Secure the tripod as needed to prevent toppling.

There are more articles in our knowledge base on our website as well.

http://www.celestron...a=view&group=C3

#11 David Rivas

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Posted 23 May 2009 - 01:10 PM

Rod, Edd, Hubert, Tony, Thanks!!!
Uncle Rod, it's an honour!!!
Tony, your input covers all the viewpoints!!
Thanks a lot, I have learnt a lot thanks to each one of you!!!
Bests,

David

#12 Luigi

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Posted 23 May 2009 - 06:05 PM

If all else fails, you can rig up a wedge to put between the base of the mount and the top of the tripod so that you can tilt polar axis to the necessary angle. There is no need for the base of the mount to be level. My choice would be a chunk of metal but hard wood could be used. Consider the CG and propensity for toppling is you do this.

#13 kwkee

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Posted 25 May 2009 - 12:21 AM

Or use a half pier so that the everything remains stable.

I remember I have to tie the original north leg with a weight when the counterweight is between the back two legs. Otherwise chances of topple is very high.

Get a half pier just to be safe. It's far cheaper than a broken scope or a broken camera.






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