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I recently purchased my first scope, a Celestron Astromaster 130EQ

Any stargazing I had done before now was done either looking through someone else's gear or at a public night at an observatory (spent many an hour in the HR Macmillan Observatory in Vancouver)

This meant that up until I got my own scope I had never had to deal with alignment of the scope.

Well now I seem to have run into a brick wall, I just can't seem to get the alignment right and it's driving me nuts.

I put the 20mm eyepiece in.

I set the tripod so it is facing north, I double and then triple check it just to be sure. (I do this using a compass and have one leg pointing south)

I set the alt scale to around 52 (according to a gps app on my phone i'm at 52.4)

I set the DEC dial to 89 degrees

I set the RA axis so it is directly vertical.

Now everything I have read and every video I have seen says that polaris should be visible in the eyepiece with minimal adjustment but I seem to have to hunt for it. (this probably just takes practice)

When I do have it I verify it by centering it in the eyepiece and waiting a few minutes to be sure it is still centered.

I then rotate my RA dial to 2.5

Now after all this I would expect the mount to be properly aligned.

So I look up Arcturus and find that it is located at RA 14.3 DEC 19.1

so I spin round everything to those numbers, cross my fingers and look through the eyepiece and it's not there so the hunt is on.

And this is repeated no matter what object I try and look at set the RA and DEC and the item is nowhere to be seen so I have to hunt for it.

My only conclusion is I have to be doing something wrong because whenever I looked through other peoples scopes they would just set RA and DEC and they would be on the object.

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Hi Larkspeed, The RA and DEC scales on mounts are notoriously inaccurate! I believe that most people on the forum who have been using telescopes for years never use them. It's a bit like the "Pirates Code" in Pirates of the Caribbean, they are more guidelines as actual rules! :grin:

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I then rotate my RA dial to 2.5

Better start by saying I know nothing about RA/Dec and have never used it, nor looked into it.

Why 2.5 ?

I do not use RA/Dec so it is guesswork but at very close to 7 degrees East I would have thought that 2.5 was incorrect - it seems to match nothing.

7 degrees East is 28 minutes I cannot see where 2.5 comes from.

I could see you setting 28 minutes (0.5 hr) or 7 deg but not 2.5 anything.

Is the "2" part to do with European time being taken into account?

If so I would set everything according the UTC time.

Lesson learnt some time ago was don't try to play with timezones, it usually goes wrong.

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If it's just for visual use for the moment I wouldn't even bother aligning it to be honest. Set the latitude on the alt scale and point the mount roughly north, then just get on with viewing. That should be good enough.

James

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I thought it would help as he doesn't mention using the RA or DEC to align as said above the scales are so small on these and the smaller scopes like mine there not accurate your better aligning your scope up with a star setting red dot finder and using that you will find things much easier then, i use a Telrad something very similar and found loads i don't use the scales.

Edited by wookie1965

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I recently purchased my first scope, a Celestron Astromaster 130EQ

I set the tripod so it is facing north, I double and then triple check it just to be sure. (I do this using a compass and have one leg pointing south)

t.

I might be wrong here, I'm just picturing it in my head and I have a skywatcher....but one leg should be pointing North and not South, this would suggest the mount is pointing the wrong way from the start, ignore me if I'm getting it wrong

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It is not necessary to level an Eq mount, however, if you are after an accurate polar alignment it makes it much easier because you are putting the RA axis at the correct latitude for Polaris (as long as you have set the latitude scale) It only takes a couple of minutes so I always do it anyway

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Better start by saying I know nothing about RA/Dec and have never used it, nor looked into it.

Why 2.5 ?

I do not use RA/Dec so it is guesswork but at very close to 7 degrees East I would have thought that 2.5 was incorrect - it seems to match nothing.

7 degrees East is 28 minutes I cannot see where 2.5 comes from.

I could see you setting 28 minutes (0.5 hr) or 7 deg but not 2.5 anything.

Is the "2" part to do with European time being taken into account?

If so I would set everything according the UTC time.

Lesson learnt some time ago was don't try to play with timezones, it usually goes wrong.

Because Polaris is at a right ascension or 2h 30m so when centered if you manualy turn the RA scale to 2.5 or 2h 30m then your RA scale should be aligned correctly.

I don't know why you brought time into it as time has nothing to do with RA and DEC those numbers remain the same for any given object no matter where in the world you are or what time it is.

for instance Vega has has a RA of 18h 36m and a declination of +38 degrees 47 minutes. and a properly aligned scope with acurate RA and DEC whells set to those coordinates would be looking at Vega, it would not matter if you were in Paris or Sydney the numbers do not change.

Time only comes into it if you are using a Alt/Az mount.

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I might be wrong here, I'm just picturing it in my head and I have a skywatcher....but one leg should be pointing North and not South, this would suggest the mount is pointing the wrong way from the start, ignore me if I'm getting it wrong

Sent from my iPhone using Tapatalk - now Free

You have a point. If a leg is pointing north, and another pointing south. Surely the tripod would fall over.

Now everything I have read and every video I have seen says that polaris should be visible in the eyepiece with minimal adjustment but I seem to have to hunt for it. (this probably just takes practice)

I may be wrong ( i am not familar with this set up ) but on an EQ mount normally Polaris is aligned to the mount, and not to the telescope.

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I may be wrong ( i am not familar with this set up ) but on an EQ mount normally Polaris is aligned to the mount, and not to the telescope.

Correct.

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I might be wrong here, I'm just picturing it in my head and I have a skywatcher....but one leg should be pointing North and not South, this would suggest the mount is pointing the wrong way from the start, ignore me if I'm getting it wrong

Sent from my iPhone using Tapatalk - now Free

Depends

When you go and look at tutorials a lot of them say the back leg should point south.

Another video I watched today had it pointing north.

So it can be done both ways apparently.

Surely the position of the tripod legs is not that important, it would be which way the mount on top of it is pointing that would matter.

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yes but if the mount is pointing stright at polaris so is the telescope

Not necessarily.........Cone error for instance.

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I'd really not worry about which way around the tripod legs point. Some tripods must have a specific leg pointing north because the az adjustment peg sticks out of the top of the tripod head on the same side and the mount is designed with the az adjustment on the north side. Others may be different.

It looks to me as if your mount doesn't have any az adjusters. That being the case the tripod can go any way around you like as long as the "high" end of the RA axis (the end where the saddle for the scope is) points north and the low end points south (for the northern hemisphere).

James

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Have you a finderscope/red dot/telrad finder? If so is it in line with the scope itself?

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Hi Larkspeed,

I did exactly the same when I got my first scope, s.w 150 pl. I soon found out a telrad and a good map was the answer to finding my way about. For visual, as long as you are pointing somewhere towards north you should be ok.

Good luck

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Have you a finderscope/red dot/telrad finder? If so is it in line with the scope itself?

Just the original Celestron red dot finder which is about as useful as a screen door in a submarine.

Hi Larkspeed,

I did exactly the same when I got my first scope, s.w 150 pl. I soon found out a telrad and a good map was the answer to finding my way about. For visual, as long as you are pointing somewhere towards north you should be ok.

Good luck

I have read that a lot unfortunately I have to make do with what I have because I can't afford to spend any more money one it. It took me over 2 years just to save the cash for the scope itself. I realize Telrads are not that expensive but it's just too much for me.

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Like others have said, I think you are relying on the axis scales too much. They really are next to useless, mere decoration, especially on cheaper mounts, and i don't recognise them numbers you are using. I would suggest that you forget them, get a decent star map and learn how to star hop, it's more fun that way anyway and you will soon be finding objects. A Telrad or a finder scope would be useful but your red dot finder will get you going and give you practice

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