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View Full Version : Aligning a Meade DS-2130-AT-TC



Rowen
2010-Oct-21, 04:36 PM
I have studied astronomy for over 25 years and only this year that I got possession of my first telescope. I love astronomy, and have a passionate interest in cataclysmic variables. I feel a need to study them and do some real science. However, all credit to Meade, countless attempts to follow their instructions on aligning my scope have failed. I have been watching Jupiter and it's moons, Venus and Mars as well as the Moon but I am manually targeting them, and not using the auto targeting system.

I level the scope as precisely as possible, point it to true north using a compass and accounting for my position in North America (9 degrees off magnetic). But when I run the test for the first target star, it points nowhere near the star's true location.

Before I start designing and building a better tripod for my mount to make it easier and faster to level and point north I would like some advice of those who are experienced.

Thanks in advance for any assistance.

RickJ
2010-Oct-21, 08:31 PM
Most of the time it is some mistake by the operator. Cheap go to scopes like this require every step be followed exactly from start up to shut down. This is where a local club would be your best bet. They can catch the mistake quite easily.

Of course we all found everything without go to. I don't use goto for visual observing as anything I want to see down well past 14th magnitude is easy to find manually once you learn the sky. I prefer to put the money in the scope and its optics rather than a goto that is problematic at best.

You give far too little information to help from here. If it is consistently missing by the same margin it could be that the time isn't entered correctly. Be sure all slop is removed from the mount. The ones I've seen brought to Hyde Memorial Observatory when I was a supervisor all had severe slop that prevented accurate pointing and made manual use difficult as well. That was easily fixed. Not being the one who helped beyond that I can only guess. Each of these seemed to work differently and we only had one volunteer expert enough to know most of them. Time entry and improper parking on shut down where the two most common problems he said he saw.

Google astronomy clubs and you'll find several services for locating one near you. Highly recommended to do this before buying a scope on your own as at their star parties you learn what works for you and what doesn't. There you will find the help you need.

Rick

Rowen
2010-Oct-21, 08:46 PM
Thanks for the reply, RickJ. I understand about the go to and, until now, was only tempted to give up on it and actually learn the sky as you say. It's nice to see that I was not off the mark. I did some initial checking for clubs locally but got far too busy to follow up on them. Now that life is more quiescent I'll be able to pursue that. Well, it's time to really bone up on the sky now ;).

Thanks again.

chrlzs
2010-Oct-21, 09:52 PM
As Rick said, we need a bit more detail. Have you reset and rechecked everything? You *must* have the correct date, time info set - check this thoroughly and make sure you haven't mucked up the AM/PM/24hr business. Then check your country/city settings. I would suspect it is one of those that is in error. A small misalignment of north wouldn't be a big problem, but I'd suggest that you use a streetmap to make sure you really have north worked out accurately.

And what happens as you use the alternative methods, eg a one or two star alignment - do no methods work? Are the stars it picks visible? Are you sure of the identity of those stars?

Like Rick, I'd guess it is something obvious that you'll kick yourself for, so get someone to watch and help go thru each step. If all else fails, back to the store (it's possible it is faulty, I s'pose) or your nearest astronomy club. Talk to them first and ask if you could bring your scope along.

Rowen
2010-Oct-22, 12:02 AM
As Rick said, we need a bit more detail. Have you reset and rechecked everything? You *must* have the correct date, time info set - check this thoroughly and make sure you haven't mucked up the AM/PM/24hr business. Then check your country/city settings. I would suspect it is one of those that is in error. A small misalignment of north wouldn't be a big problem, but I'd suggest that you use a streetmap to make sure you really have north worked out accurately.


It's been a few months since I ran through the procedure. When I did I always started from the very beginning in and off state. Thinking back it could have been a leveling issue, but the memory is cloudy now.



And what happens as you use the alternative methods, eg a one or two star alignment - do no methods work? Are the stars it picks visible? Are you sure of the identity of those stars?


No matter the alignment method none of the stars match, mind you I still don't know my sky so I can't be certain of the identity. The stars it picks are visible, they are the brightest at whatever time I'm viewing.

I have the option of using my new GPS for location. So, I ask if the Regina city selection has enough of an error margin to cause this problem, and will the GPS improve the location enough to compensate for any error?



Like Rick, I'd guess it is something obvious that you'll kick yourself for, so get someone to watch and help go thru each step. If all else fails, back to the store (it's possible it is faulty, I s'pose) or your nearest astronomy club. Talk to them first and ask if you could bring your scope along
.

Lol. I'm certain it's something I'm doing. Telescope operation is a new aspect of this passion so the chances are real good that it is me and not the scope. I'll take both your advice and contact the local club, see if I can start joining their star parties.

TYVM

chrlzs
2010-Oct-22, 09:44 PM
...No matter the alignment method none of the stars match, mind you I still don't know my sky so I can't be certain of the identity. The stars it picks are visible, they are the brightest at whatever time I'm viewing.

Hmm. If you don't know your sky that well, how can you be sure that they are the right ones? Maybe grab a printed star atlas to help there. Or we can probably help if you tell us your location and at what time you are looking up!


I have the option of using my new GPS for location. So, I ask if the Regina city selection has enough of an error margin to cause this problem, and will the GPS improve the location enough to compensate for any error?
If you pick the nearest city, there shouldn't be any problem of the magnitude you are reporting. Is that Regina, Saskatchewan?


Lol. I'm certain it's something I'm doing. Telescope operation is a new aspect of this passion so the chances are real good that it is me and not the scope. I'll take both your advice and contact the local club, see if I can start joining their star parties.

Yep. Do not pass GO... :D Once you have got it working, you will never look back (or down..)...

PS - Have you got a decent planetarium program on your PC? That will help - go visit www.stellarium.org - it's a great (and free) program.

Rowen
2010-Oct-23, 01:25 AM
Hmm. If you don't know your sky that well, how can you be sure that they are the right ones? Maybe grab a printed star atlas to help there. Or we can probably help if you tell us your location and at what time you are looking up!


Actually, I did consult a sky map, which is how I discovered how off it was. Even with an untrained eye it was quite clear to me that there was a problem.



If you pick the nearest city, there shouldn't be any problem of the magnitude you are reporting. Is that Regina, Saskatchewan?


Yes actually.



Yep. Do not pass GO... :D Once you have got it working, you will never look back (or down..)...


The more obvious targets kept me busy and got me used to the scope operation enough to be comfortable with it.



PS - Have you got a decent planetarium program on your PC? That will help - go visit www.stellarium.org - it's a great (and free) program.

Stellarium is what I got! I actually got it to control my scope. I also have the software Meade supplied (though it isn't compatible with anything higher than Windoze 98) as well as Celestia and another on my netbook I don't remember the title of.

RickJ
2010-Oct-23, 01:58 AM
I know I'm a stuck record on this but there's a great astronomy club in Regina. http://www.astronomyregina.ca/ They will make your journey into astronomy many times easier than trying to go it alone. The learning curve is steep. A club can make the journey far more enjoyable.

Rick

Rowen
2010-Oct-23, 02:08 AM
Rick, your efforts are very appreciated. I will not delay and will make the time Monday to check them out. I may even be able to swing the funds for a membership.

Thanks to both of you again

Rowen
2010-Oct-24, 02:26 AM
Hey, guys. Tonight it was just clear enough to try this alignment again, to get that extra info you needed. Please, bear in mind that I am not yet used to what an arc minute or second etc looks like, I'm sure this will come once I can get this alignment down. Anyway...

Date: 10/23/10
Time: 7:50pm to 8:00pm
Location: Regina, Saskatchewan
Alignment Used: Easy (2 star)
Software Used: Stellarium
Stars used: Vega, Altair

Procedure Test 1:
1) Leveled tripod
2) Pointed scope north (9 degree offset from magnetic). It may have been off just a little.
3) Set Altaz to home (I assume 0) and elevation to 0
Attempted to target Vega first (scope nearly straight up but pointing west). Elevation was too low by 2.5 thumbs width (my thumb is 1" wide held at arm's length) and too far north by approx 1/4 thumb width.
Attempted to target Altair second. Elevation was too low by 2 thumbs width and too far east by approx 2/3 thumb width.

After this test I parked the scope via the controller command and adjusted the Altaz by loosening the scope base from the tripod and shifting it to the right a touch. I then thought after I started the 2nd test that it should have been to the left instead. But I am uncertain. I am including this first test anyway as it may be helpful.

Procedure Test 2:
Attempted to target Vega. Elevation was too low by 2.5 thumbs width and too far north by approx 1/4 thumb width.
Attempted to target Altair second. Elevation was too low by 2 thumbs width and too far east by approx 1/2 thumb width.

I parked the scope again and shifted the Altaz by loosening the scope base from the tripod and shifting it to the left a touch. It was then that I realized that just a little difference when aligning north makes a big difference, so I stuck with it.

Procedure Test 3:
Attempted to target Vega. Elevation was too low by 2.5 thumbs width and too far north by approx 1/4 thumb width.
Attempted to target Altair second. Elevation was too low by 2 thumbs width and too far east by approx 1/2 thumb width.

I think this confirms that it is mostly me that is in error when it comes to the alignment north. However, it also seems to me that the elevation is consistently too low by the same amount for both Vega and Altair. The scope parks properly to 0 every time so I conclude it is not a problem with the motor. However, at the time I am writing this I took a look at the scope and it is pointing up about 3 degrees from perfectly horizontal. This appears to be off by the same amount it is off by elevation, but in the wrong direction. I will be going over the assembly again. I am certain I followed it correctly as I triple-checked the instructions at each step.

It will be overcast for the next few nights, so I won't be able to repeat the test again for maybe a week. But I will perform a few more tests and log the results here. Will keep you posted.

Rowen
2010-Oct-24, 09:17 AM
I think I have discovered the problem. I believe it is my tripod. It is cheap and nearly impossible to level. I am currently considering a couple strategies when the sky clears again before I buy or design a new one.