Hi
Does anyone here own a telescope from Celestron's AS-GT Series? I'm curious to know how you align, balance your scope & etc...
Thanks!
Celestron AS-GT Series
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weixing
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Hi,
Anyway, balance it as normal EQ mount and the alignment is also quite easy, but you need to do a rough polar alignment first. The more accurate the polar alignment is, the more accurate the GOTO will be.
By the way, your question is a bit too general... you need to be more specific on what you wish to know about the mount.
Have a nice day.
PS: Welcome to SingAstro.
You mean the CG5-GT??? I don't own one, but use it for a few times.Does anyone here own a telescope from Celestron's AS-GT Series? I'm curious to know how you align, balance your scope & etc...
Thanks!
Anyway, balance it as normal EQ mount and the alignment is also quite easy, but you need to do a rough polar alignment first. The more accurate the polar alignment is, the more accurate the GOTO will be.
By the way, your question is a bit too general... you need to be more specific on what you wish to know about the mount.
Have a nice day.
PS: Welcome to SingAstro.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance." No I'm not necessarily refering to the CG5-GT but rather to any scope using the CG-5 mount (sorry, should have been more specific there).
Also, many reviews say that this mount is not suited for lattitudes lower than 30 degrees.
Thanks!
I'm sorry, but I don't understand how the mount can be balanced with polar aligning. If I turn the CG-5's head 180 degrees to leave room for the counterweight shaft, it will be unbalanced.Anyway, balance it as normal EQ mount and the alignment is also quite easy, but you need to do a rough polar alignment first. The more accurate the polar alignment is, the more accurate the GOTO will be.
Also, many reviews say that this mount is not suited for lattitudes lower than 30 degrees.
Thanks!
-
weixing
- Super Moderator
- Posts: 4708
- Joined: Wed Oct 01, 2003 12:22 am
- Favourite scope: Vixen R200SS & Celestron 6" F5 Achro Refractor
- Location: (Tampines) Earth of Solar System in Orion Arm of Milky Way Galaxy in Local Group Galaxies Cluster
Hi,
I'll explain it as detail as possible and this basically can be applied to all German Equatorial (EQ) mount. The setup of EQ mount basically require two steps:
1) Rough Polar Alignment and
2) Balance your scope
1) Rough Polar alignment
For EQ mount to operate as what it is design for, you need to alignment the EQ mount to north or south depend on which hemisphere you are in. In Singapore, you are just above equator toward the north, so we align to the north. Using a compass to point your EQ mount (the side with the 'N" mark) toward the North pole as accurate as possible. Also, adjust the altitude of the mount to slightly more than 1 degree (Singapore latitude)... I think the CG5 mount may be able do it, but the CG5-GT will have problems.
2) Balance your scope
In order to operate your mount as smooth as possible and reduce the stress on your mount gear, you need to balance your scope. It involve two step: Balance the R.A. axis and balance the DEC axis. But first mount your scope, connect all the necessary accessories that you are using on your scope (finderscope, 1 x diagonal, 1 x eyepiece, and etc) and put the counter-weights on the counter-weight shaft and tighten the counter-weight screws. The counter-weights should be around the same weight as your scope and the accessories that going to put on your scope.
R.A. Balancing
1) Unlock the R.A. and rotate the scope unitl both the optical tube and counter-weight shaft is horizontal to the ground. Lock the R.A. first and unlock the DEC and rotate the optical tube around DEC axis until the optical tube is also parallel to the ground.
2) Lock the DEC and unlock the R.A.
3) Unlock the counter-weights screws and move counter-weights along counter-weight shaft until scope is balanced and remains stationary when released.
4) Tighten the screws that hold the counter-weights in their new position and lock the R.A.
DEC Balancing
1) Unlock the DEC.
2) Slowly release telescope and determine which direction the telescope rotates. Loosen telescope tube clamps and slide telescope tube forward or backward in the clamps to balance DEC axis.
3) Once telescope no longer rotates from its parallel starting position, re-tighten tube clamps and lock the DEC.
After all these, your EQ mount is ready for action. Can do a more accurate polar alignment if you got a motor drive and require more accurate tracking.
Have a nice day.
PS: Your EQ mount manual should have a more details description with pictures.
I don't mean that the mount can be balance with polar alignment... they are two sperate thing.I'm sorry, but I don't understand how the mount can be balanced with polar aligning.
I'll explain it as detail as possible and this basically can be applied to all German Equatorial (EQ) mount. The setup of EQ mount basically require two steps:
1) Rough Polar Alignment and
2) Balance your scope
1) Rough Polar alignment
For EQ mount to operate as what it is design for, you need to alignment the EQ mount to north or south depend on which hemisphere you are in. In Singapore, you are just above equator toward the north, so we align to the north. Using a compass to point your EQ mount (the side with the 'N" mark) toward the North pole as accurate as possible. Also, adjust the altitude of the mount to slightly more than 1 degree (Singapore latitude)... I think the CG5 mount may be able do it, but the CG5-GT will have problems.
2) Balance your scope
In order to operate your mount as smooth as possible and reduce the stress on your mount gear, you need to balance your scope. It involve two step: Balance the R.A. axis and balance the DEC axis. But first mount your scope, connect all the necessary accessories that you are using on your scope (finderscope, 1 x diagonal, 1 x eyepiece, and etc) and put the counter-weights on the counter-weight shaft and tighten the counter-weight screws. The counter-weights should be around the same weight as your scope and the accessories that going to put on your scope.
R.A. Balancing
1) Unlock the R.A. and rotate the scope unitl both the optical tube and counter-weight shaft is horizontal to the ground. Lock the R.A. first and unlock the DEC and rotate the optical tube around DEC axis until the optical tube is also parallel to the ground.
2) Lock the DEC and unlock the R.A.
3) Unlock the counter-weights screws and move counter-weights along counter-weight shaft until scope is balanced and remains stationary when released.
4) Tighten the screws that hold the counter-weights in their new position and lock the R.A.
DEC Balancing
1) Unlock the DEC.
2) Slowly release telescope and determine which direction the telescope rotates. Loosen telescope tube clamps and slide telescope tube forward or backward in the clamps to balance DEC axis.
3) Once telescope no longer rotates from its parallel starting position, re-tighten tube clamps and lock the DEC.
After all these, your EQ mount is ready for action. Can do a more accurate polar alignment if you got a motor drive and require more accurate tracking.
Have a nice day.
PS: Your EQ mount manual should have a more details description with pictures.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance." 
can go down to 10 degrees by just replacing the azimuth knobs, a bit more modification required to bring it down to 2 degrees (or can just tilt the tripod legs to compensate). this is related to the GOTO version of the mount.Also, many reviews say that this mount is not suited for lattitudes lower than 30 degrees.
Hi,
I have the CG5 mount.
Apparently they have 2 versions of the tripod. The one for the lower latitudes (<30deg) allows the counterweight shaft to swing between the 2 front legs.
There is a bracket in front (behind the RA housing) for a screw that locks the latitudee setting to prevent it from tilting up. This bracket is secured by 2 screws. For our latitude, this is redundant and can be safely removed. If this is removed, you do not need to remove the RA housing.
Removal of this bracket (simply a metal piece with a treaded hole in the centre) will allow the head to go all the way to zero. If the counter weight hits the legs, use more weights but shift it higher.
Kay Heem
I have the CG5 mount.
Apparently they have 2 versions of the tripod. The one for the lower latitudes (<30deg) allows the counterweight shaft to swing between the 2 front legs.
There is a bracket in front (behind the RA housing) for a screw that locks the latitudee setting to prevent it from tilting up. This bracket is secured by 2 screws. For our latitude, this is redundant and can be safely removed. If this is removed, you do not need to remove the RA housing.
Removal of this bracket (simply a metal piece with a treaded hole in the centre) will allow the head to go all the way to zero. If the counter weight hits the legs, use more weights but shift it higher.
Kay Heem