EQ5 Assembly problem?

[Catweazel]

Hi,

I have just got my new scope with EQ5 mount. I have put all together, and think (?) that I have it all right. However, there are 2 bolts with diagonals on them which are supposed to be for the ALT/AZ adjustment. The bolts are different lengths, I put them where the diagram says they should go (though it gives no indication of which length bolt goes in which hole?). my problem is that the AZ bolt (shorter one?) doesn't seem to do anything? The ALT bolt, although it works, the black altitude dial shows that the scope is resting in the mount at 28 degrees, when I turn the bolt it will tilt the scope to 58 degrees before becoming too tight to turn any more. Should the mount not tilt from 0 - 90 degrees? Have I set the mount up wrongly in some way

Any help/advice much appreciated.

[Catweazel]

Sorry for double post, but having had another look at the EQ5, I have worked out what the bolts do (you loosen one then tighten the other) and been able to change the RA axis.

Just to clarify what I understand as the way the mount should work: I assume that once the scope is balanced & polar aligned, I can then unlock the RA & dec and swing the scope around until I find something I want to look at, then lock the RA & Dec and use the slo-mo controls to fine tune the scope to the object. This is a guess on my part, as I also struggle to see what the polar alignment is for, if I am not keeping the scope in the 'home' position? (i.e once I move the scope, how does it stay aligned?)

[Photosbykev]

Polar alignment aligns the mount to NCP (Polaris) rather than aligns the scope.

[Bizibilder]

Polar alignment aligns the Polar axis with the North Celestial Pole (on an EQ5 you can remove the caps and look through the polar axis or polar scope if you have one fitted) - The polar axis is the one at an angle equal to your latitude (about 52°). You rightly say that you find an object by loosening both axis and moving the scope to centre your object. You then tighten both clutches (the black plastic levers).

To follow an object with a perfectly aligned mount you then only have to rotate the polar axis slow motion - the dec axis slow motion is not necessary. In the real world, however, your mount won't be perfectly aligned, so you may need an occasional tweak of the dec axis slow motion to keep an object centered.

The whole scope is then revolving around the polar axis only - hence the need for alignment. To see what is going on point the scope near the eastern (or western) horizon. Lock the dec axis and swing the scope round the polar axis only. The scope will follow an arc from east through south to west (until it hits the mount!). Try this a few times - in daylight is easier - and you will soon see how the mount behaves following different arcs across the sky.

[Catweazel]

Polar alignment aligns the mount to NCP (Polaris) rather than aligns the scope.

Ahh, I see. yes, that puts it into perspective; I was confusing the polar alignment of the mount with the movement of the scope. So, once the mount is aligned, as long as I don't move the mount/tripod, I can move the scope around on the mount to find stuff to look at, then use the RA dial to track the object. Got it

Thanks very much Photosbykev!!

Now I just have to wait for a clear sky

[malc-c]

To be honest the dial on most Skywatcher scopes are useless, but they should more or less point you in the right direction of North South East or West

[E621Keith]

To be honest the dial on most Skywatcher scopes are useless, but they should more or less point you in the right direction of North South East or West

I think he meant the slow motion hand knob rather than the setting circles when he said the RA dial.

While the DEC setting circle is useless, the RA setting circle very important for polar alignment. However, I agree both setting circles are useless for finding things.

[Catweazel]

I think he meant the slow motion hand knob rather than the setting circles when he said the RA dial.

While the DEC setting circle is useless, the RA setting circle very important for polar alignment. However, I agree both setting circles are useless for finding things.

Hi Keith, yeah, I did mean the slo-mo knob. I guess when you talk about setting circles you mean the numbered dials. I assumed that these were for finding precise coordinates, but I have no idea how to use them As they sound hopeless anyway, it's no great loss I suppose.

With regard to RA and polar alignment, the mount came with a polar scope pre-fitted, do I just look through it and use the altitude bolts to align with polaris with 'N' on tripod facing north? Where does the RA setting circle come into play?

many thanks. CW

[E621Keith]

The setting circle on these mount are too small for finding things. The dec axis circle is marked in 2 degrees increment, that's 4 times the diameter of the moon!!! The only use for those setting circle is for polar alignment.

Polaris is not located on the NCP but just under a degree off. When you look through the polar scope, you should see the cross hair and there will be a circle or a mark of some sort on one of the arms. That mark is the point where you should place Polaris.

Polaris rotate around the NCP once a day, so the corresponding point on the polar scope needs to be changed.

1. On the 1st November, Polaris will be directly above the NCP at midnight. Turn the RA axis so the Polaris mark is directly below the centre of the cross hair (because the polarscope produce inverted image). Lock RA axis.

2. Set the RA setting circles to 1st Nov, 0:00. This zero the polarscope. Then you should move the hour dial to compensate for the difference between your local time to your time zone meridian. Southampton where I live is only around 5 minutes behind Greenwich so I never bother with the correction.

2. Lock the hour setting circle and then turn the RA axis until the date circle matches the today's date.

3. Unlock the hour circle and turn the RA axis until the time matches the current time.

4. Lock the RA axis. You polarscope's polaris mark is now should the location where polaris should be. You can then polar align your scope by putting polaris into the polaris mark.