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digital_davem

EQ2 mount - no clue where to start!

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Hi

I've just acquired a skywatcher 130P  650/f5 on a Eq2 outfit for the princely sum of £45. And I have no idea how to use the EQ mount (used to Alt-az).  It's got a lot of knobs and scales but where to start?

There are no instructions but even if there were I don't think they would be helpful judging from the online version which devotes 2 sentences to set up...

Cheers

Dave

 

 

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I found the attached a great help when I got mine. Page one covers putting it all together which I guess you've probably nailed already so I've linked straight to page two. It covers the basics of polar alignment and usage once you're setup.

Mine's an SW 130 and while at the start I'll admit to a little envy looking around the boards at some of the gear people have, but I've been nowt but delighted overtime I've used it. :)

Also worth noting they're not demonstrating with an EQ2 but it's all the same, R/A, DEC, knobs etc.

S@N Equatorial Setup Guide

Edited by johnfosteruk

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For £45 on an EQ2 the 130P is a very capable scope to start with and a cracking bargain. I remember mine (which was my third scope) fondly. Enjoy! :)

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53 minutes ago, digital_davem said:

Hi

I've just acquired a skywatcher 130P  650/f5 on a Eq2 outfit for the princely sum of £45. And I have no idea how to use the EQ mount (used to Alt-az).  It's got a lot of knobs and scales but where to start?

There are no instructions but even if there were I don't think they would be helpful judging from the online version which devotes 2 sentences to set up...

Cheers

Dave

 

 

Hi Dave,

Here is a link to the Skywatcher user manual for the EQ2 and scope.


http://www.apm-telescopes.de/media/manuals/skywatcher/en/13.pdf.

 

Hope it is of some help.

 

Sandy.

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Thanks, folks.

I managed to get out and look at the moon and jupiter briefly last night but I was just pushing and shoving the scope randomly!

What I've learnt so far:

- an EQ mount has 4 axes:  left/right to local horizon; up/down altitude for setting latitude; RA; declination. 

- the first two are just for set up, the latter for actually pointing the scope

- there is a big silver wheel attached to a worm drive on the RA axis - this is slow motion control for tracking targets. This had a strange piece of tin next to it (a thin round plate with a notch cut out of it and a bit sticking out to move it with. No idea what this is for, looks too flimsy to do anything.

- the RA and Dec axes have setting circles but the DEC one is fixed while the RA one spins round. No idea why.

- There are large knobs on the RA and Dec axies that appear to release the mount and allow free movement. Presumably you release these to swivel to your target, then tighten and track with the slow motion control?

- I obviously need to align the scope to Polaris somehow but the guides I've looked at quickly don't seem entirely clear how this is done. Will need to study them more carefully

- I need to do something with the counterweight to balance the scope but the guides seems a bit handwavey as to exactly the steps to follow. Need to study this more carefully.

It's a second hand scope previously used by a young lad for astronomy GCSE. Probably need to check collimation before serious use, so another thing to learn how to do.

It's a bit more complicated than my Vixen Porta 2!

 

 

 

 

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In terms of balancing, the way to do this is one axis at a time.   Release the Dec clutch and see if the tube feels balanced as you swing it around.   If it doesn't then you will need to loosen the locking rings around the tube, slide the tube up or down a bit, and re-lock the rings, and do this until you have the tube balanced.    Then lock the Dec Clutch and release the RA clutch and see if it is balanced in that direction.    If not you need to move the counter weights up or down.

Here are some fairly detailed instructions for alignment specific to your EQ2 mount, assuming the design has not changed over the last 3 years.

Once the telescope is in place and balanced at the start of viewing session the set up procedure is:

-       - Using the adjustable legs, make sure the telescope is level, i.e. the accessory tray is level (I use a spirit level to check this)

-        - Make sure the latitude setting is roughly right at about 51.5 degrees for London.

-        - Release the Dec clutch and rotate the telescope until the dial is showing 90 degrees.   The pointer is at the bottom of the Dec dial.   Tighten the Dec clutch.

-        - Release the RA clutch.   You will be able to swing the telescope in an arc from side to side.   You want to swing it to the position where the telescope is at its highest point and the weights are at their lowest and then tighten the clutch again

-       -  You now have the telescope in its “home” position.

-        - With the telescope in its home position you need to make sure it is pointing north.  But do NOT do this using the Dec and RA controls to move it to the north position.   Instead, loosen the knob underneath the top of the tripod, rotate the whole mount and telescope and tighten the knob again when you have the telescope pointing north according to a compass.    Now you have the telescope roughly set up and it will track objects pretty using just the RA fine control once you have them in view.   As it will not be precisely lined up you may need the occasional tweak of the Dec fine control.

If you want to line it up more precisely, you should make sure it is pointing at Polaris, the north star.   Again release the knob below the top of the tripod to get the left-right alignment correct and then tighten the knob.   Adjust the latitude fractionally to get the up-down alignment correct, supporting the weight of the tube as you do so.    Firstly try to get Polaris lined up with the red dot finder, and then in the middle of the eyepiece view.

For even more precision you need to be about 1 degree off from Polaris.   Which direction depends on the time of year and time of day.    Stellarium is a good way of seeing which direction.

Whether you line it up roughly, precisely or very precisely is up to you.   Once it is lined up you won’t need to touch the knob under the top of the tripod head or the altitude setting again in your viewing session.    You will always move the telescope where you want it using the Dec and RA controls, and once you have your target in view through the eyepiece you will be able to track it using mainly (or entirely) the fine RA control.

My advice would be to do it the rough method for the first couple of sessions until you get used to the telescope and then worry about lining up to Polaris once you have mastered using the telescope a bit.  

Hope that helps.

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For visual use, polar alignment does not have to be overly precise. The important thing is that you point the upper side of the mount (not the scope) towards the north. Just find the big dipper and from there Polaris. Point the scope roughly at it. Then go down on one knee and look along the mount towards Polaris. Then you move the tripod legs until the mount is correctly in line with Polaris. All this time the scope could be pointing anywhere. This will take approx 20 seconds.

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I recently bought 150p on eq3-2 from Rother Valley and by mistake they sent me 2 DVD's which are great on setting it all up etc. I can send you one if you send me your address.

Not sure if there is a way of sending private message on here

 

 

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Couple more questions...

1. When moving the scope around the dec and RA axes it moves very smoothly most of the time but there seem to be some positions where the is a slight resistance to moving and you have push it harder. Is this normal?

2. What's the metal thing that is next to the slow motion knob on the RA axis? It's a piece of thin flat circular metal about an inch is diameter with a notch on one side and a sticky out piece. It is bolted to the mount such that it swivels freely most of the time just behind the slow motion knob, but in one position it touches the slow motion shaft. It looks almost like it was supposed to be some kind of crude brake but it doesn't seem to have an obvious use. It is not mentioned in the manual,although it appears in the diagrams.

 

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27 minutes ago, digital_davem said:

Couple more questions...

1. When moving the scope around the dec and RA axes it moves very smoothly most of the time but there seem to be some positions where the is a slight resistance to moving and you have push it harder. Is this normal?

2. What's the metal thing that is next to the slow motion knob on the RA axis? It's a piece of thin flat circular metal about an inch is diameter with a notch on one side and a sticky out piece. It is bolted to the mount such that it swivels freely most of the time just behind the slow motion knob, but in one position it touches the slow motion shaft. It looks almost like it was supposed to be some kind of crude brake but it doesn't seem to have an obvious use. It is not mentioned in the manual,although it appears in the diagrams.

 

In answer to number two, this is used for the motor drive and acts as a cam, moving the drive on to or away from the RA worm drive thereby allowing you to switch between motorised or manual RA control.

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Don't stress too much. There are plenty of videos on youtube that will help you setting up an eq mount. As others have said, for visual observing it doesn't have to be too precise, I take mine out and stand behind it and just eye up polaris up above the scope when it's in it's start position, I have to give the declination a little tweak now and again but it's no real hardship. As for the dials, which are setting circles, these are only good for decoration really, they are not precise enough to be of any real use.

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15 hours ago, Twiggles said:

In answer to number two, this is used for the motor drive and acts as a cam, moving the drive on to or away from the RA worm drive thereby allowing you to switch between motorised or manual RA control.

I didn't actually know this. I don't use my motordrive any more as I was annoyed that you couldn't use the RA manually once it was on. Any info/links on how the cam should work? Mine just seems to spin round and wedge up against the RA axle but doesn't stay there

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The cam has a small hole at the side to attach a spring to the mount using a screw at the mount end - you should see a threaded hole where the screw goes in. Then on - it's a mechanical thing whereby you press the flange on the other side to engage the cam to the RA shaft. Pressing a second time disengages it - kinda like a tracking on/off switch. Best way I can describe it - hope you can see what I mean. :)

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10 hours ago, Twiggles said:

Best description may come from ehre, just need to read down a bit to see the pictures.

 

http://astrobeano.blogspot.co.uk/2012/01/multi-speed-motor-for-skywatcher-eq2.html

 

Mine's actually a much simpler drive that attaches to the slo-mo control side of the axle rather than the grub wheel thingy so don't think I can use the cam

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Big Thank You to Everyone

Loads of useful info on this thread and in the links.

A special thank you to Peco4321 for the DVD which was quite good and very helpful.

Collimation next....... ;-)

 

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