Using RA and Dec dials on mount

[NessieHunter]

Hi folks,

My scope has just arrived and as a complete newbie have a couple of questions. As my mount (eq3-2) does not have any goto or motors, I was wondering about using the dials to find objects in the sky. I am fairly confident about polar alignment and will have my laptop with stellarium running so my question is this. After alignment do I need to choose a known object, point the scope then set the RA and Dec dials at that point to the correct setting and then move the scope accordingly after that to the next object? Also, am I using the RA and DEC from a start chart or the coordinates in Stelllarium. Alternatively, am I just wasting my time and try star hopping?

Many thanks. Neil

[Ludd]

My gut feeling is in favour of star-hopping, partly because using the setting circles (dials) relies on you having the scope reasonably aligned and having the RA circle set by reference to a known object. Quite easily done, but sometimes star-hopping is easier, particularly if you have instructions like those in "Turn Left at Orion".

[Deano6128]

You're right in saying that you would first find an object that you know the co-ordinates for, and then changing the dials to match.

However, when I first got my scope I tried to make use of the RA and DEC dials, but soon found that they weren't really accurate enough to put an object in the FOV of the telescope.

Much better off learning the constellations and star hopping

HTH

Dean

[starguest]

Nessiehunter

I believe that EQ3-2 has a polarscope hole so might be fairly readily aligned. Once aligned the manuals always suggest going to Vega and centering it in EP. You turn the RA and DEC rings to match what it is - 18.36 38.47 - though the ring markings don't allow fine accuracy.

With that you can swing to say Deneb and see if the rings show what Deneb's coordinates should be, then another star over the other side and back to Vega. The rings should show the Vega coordinates. That means the rings aren't sticking.

Now to go somewhere you see in the chart, you start by locking one axis and move the other while watching the ring get to the coordinate. Once there lock that axis. Unlock the other and watch its ring as it gets to the coordinate. That should be the star you first thought of - well the one from the chart you chose

[NessieHunter]

Thanks guys for your feedback. Not having done it before I think I will give it a go and see how accurate (or not!) the setting circles are. Even if they are not totally accurate it should help me learn the night sky as the scope should in theory be pointing fairly close to where I want to be and I can then get a feel for the sky in relation to the charts and Stellarium. Many thanks. Neil

[Bizibilder]

For RA and Dec dials to be useful they need to be FAR better quality than those on the current type of mount ie they must lock properly and not be able to rotate at all once set! It was always said (back in the good old days!!) that dials of less than six inches in diameter were simply too crude for accurate "finding" and 8" to 10" dials were better. You would be lucky to set an EQ2 (or EQ3 or 5 or 6!!) dial to better than 2°!!

So star-hopping is the order of the day.