Celestron AstroMaster 130EQ - DEC Alignment

[CrystalFox]

Hello guys,

I recently got into astronomy so I bought my first telescope. I've read through several articles and the recommendation for a beginner's telescope (value/price) was Celestron Astromaster 130EQ-MD. I bought this from someone who was not really using it and it is in a very good condition. Prior to actually purchasing this, I've watched countless videos on how the telescope works, what needs to be done - latitude, RA/DEC alignment, polar alignment, etc..

After reading through all available manuals and videos, I finally brought it home from the seller (they've had it for around 5 years but it wasn't used much). After setting up the tripod, mounting the telescope and familiarising myself with all the different knobs, I pointed the mount/telescope towards north. The first thing I had to do was setting up the latitude. Since I am based in London, the latitude is around 52 degrees. Afterwards, I had to align the declination axis so the telescope can be balanced. As I understand it, you should be able to move it to any position on the axis and it should stay in that position. If the front or rear was heavier, I would either pushing or pulling the telescope after unlocking the brackets holding it together. This is where the issues began, I could balance the telescope so it doesn't move while in the horizontal position, however, when pointing it towards north, it would exclusively lean towards one direction - to the left. If the telescope was pointing to north, north-east or east, it would pull towards the west all the time. It is probably easier to show it in the video. I've spent three days trying to balance the telescope by using different methods and it just would not work. 

I've also tried balancing the RA axis first. This could be somehow done, but the declination axis would still pull the telescope to the left.

It is extremely frustrating as I don't know what could be causing this. Balancing the telescope should be relatively easy from what I have heard - either push it or pull it depending on where the weight is. However, I have been really struggling to get it set-up.

I would be thankful for any suggestions and please feel free to ask any questions so I can help with finding out what is wrong.

 

Thank you.

[Alan64]

It appears that the telescope needs to be moved forward a bit more within its rings.  It's bottom-heavy within the video.  The primary-mirror is located there at the back, and it accounts for a good deal of weight.

The telescope should be balanced on the DEC-axis with the axis at one side.  At 3:48...

https://www.youtube.com/watch?v=plx6XXDgf2E&t=34s

Edited September 19, 2019 by Alan64

[NGC 1502]

 

Hi and welcome to SGL, lots of folk here happy to help.

I’ve not watched the video.   However, the scope needs to be balanced in both directions.   As you know, the tube assembly can be slid within the tube rings to balance it In declination.   And in right ascension you can balance it by sliding the counterweights on the shaft.    Balancing is achieved with the lock screws on each axis released.   The balance doesn’t have to be absolutely precise, just get it as close as you can.   Balance each axis separately.

For polar alignment, many tutorials show how to achieve that to a precision necessary for astrophotography.  That precision is not required for basic observations.  Just point the polar axis north as best you can and you will be ok.

One thing to mention is the red dot finder on your scope.  At my local club over the last few years two different visitors have brought along the same scope you have for advice, struggling to use the finder. So did we when trying to help.  I’m sorry to say this, but that finder is not fit for purpose, whoever designed it didn’t understand what’s needed.  I can see that finder in your second photo.  I do realise you probably don’t want more expense, but if you want to use your scope with the least frustration, then a regular design red dot finder, available from companies like our sponsors First Light Optics, would be very well worth getting.

Hoping that helps, Ed.

 

 

 

[runway77]

Hello, I was struggling with the balancing as well. I could not balance it, especially after I put an eyepiece into the focuser. However, then I tried it this way: before I started to balance it, I put the focuser in parallel to the counterweight axis, basically in upwards direction. Then I locked the declination clutch, moved the telescope along RA and balanced the counterweights. Remember, there are two counterweights, they need not to be together, you can move them separately. When one is locked, you can precisely balance the telescope with the other. After you balance the telescope for the RA axis, lock the RA clutch and release the Declination clutch. Unscrew the screws of the tube holder but leave them there. Move the tube so the focuser is pointing in parallel with the counterweight (declination axis). Put an eyepiece in the focuser when you are doing that. Move the tube forwards or backwards until it is balanced. This worked for me.

I suggest you to replace the red dot finder with a Telrad.

Refer to this manual:

and you NEED a laser collimator. Hopefully, there is a center doughnut on the primary mirror. If not, you have to put one there.

https://garyseronik.com/centre-dotting-your-scopes-primary-mirror/

Refer to this video as well.

Hope this helps!

 

Edited September 23, 2019 by runway77

[Asur1984]

I have the same scope. I do not have the necessary experience as yet to offer an opinion but I hoping that I can now get chance to take it out for a spin after my life has now settled down to a normal routine. 

I am interested in the replies and will look to use all the advice given when I do get a chance to get out there myself.