Setting Cirlces, Hidden Scopes and Loungeroom Astronomy.

[willpower (Will)]

So my first Telescope and Mount arrived yesterday in the middle of what seemed like a typhoon. All hopes of using her left me, given the weather reports. So I did what I assume any of you would have done. I set it up in my lounge room

Following the great instructions I found on here in Begginer's Guides, namely Trevor Hand's article on the "Basic setup procedure for a GEM", I went about learning the ropes. I assembled the scope, set the latitude, balanced everything and prepared myself for "first light" (I believe that is the expression?). Then I found something peculiar. A small cap revealing a scope within the mount itself. I looked into this online and have come to the vague conclusion that it has something to do with aligning a GEM with Polaris in the Northern Hemisphere?

This leads me to my actual question - do I, in the southern hemisphere, need to perform any alignment steps with this little scope? I.e. do I need to bring a certain star into view to obtain a southern celestial allignment?

And secondly - what role do setting circles play in aligning a GEM Goto mount?

I hope this isn't a stupid question.

My scope is goto (obviously) so I assume I'll need everything bang on to get any use from it?

Thanks in advance to any and all advice.

Will.

[dannat (Daniel)]

The little scope is for polar aligning like you thought, down here you point to octans constellation, does t have marks for it in the little scope (your goto will be better if polar aligned)

Setting circles are to help you find objects using hours deg etc. you align them on a known object, hen move them to the known time, eg locate Jupiter (which you look up & see it Is 15h25deg, you then move the set circles to match this...then use the o help locate other objects

[Barrykgerdes]

Originally Posted by willpower

So my first Telescope and Mount arrived yesterday in the middle of what seemed like a typhoon. All hopes of using her left me, given the weather reports. So I did what I assume any of you would have done. I set it up in my lounge room

Following the great instructions I found on here in Begginer's Guides, namely Trevor Hand's article on the "Basic setup procedure for a GEM", I went about learning the ropes. I assembled the scope, set the latitude, balanced everything and prepared myself for "first light" (I believe that is the expression?). Then I found something peculiar. A small cap revealing a scope within the mount itself. I looked into this online and have come to the vague conclusion that it has something to do with aligning a GEM with Polaris in the Northern Hemisphere?

This leads me to my actual question - do I, in the southern hemisphere, need to perform any alignment steps with this little scope? I.e. do I need to bring a certain star into view to obtain a southern celestial allignment?

And secondly - what role do setting circles play in aligning a GEM Goto mount?

I hope this isn't a stupid question.

My scope is goto (obviously) so I assume I'll need everything bang on to get any use from it?

Thanks in advance to any and all advice.

Will.

Hi Will

You did not say what the scope was but I assume from your signature it is an ED80 on a eq5 pro goto mount. Does it use the Synscan control system? Is it the Heq5 Pro with synscan

Yes the little scope in the centre of the RA axis is the polar scope. If you look carefully at it you will also see an arrangement of 4 stars representing Sigma octans for southern hemisphere use. The FOV of the polar scope is about 6 degrees

To get the scope to work it is essential that you get a reasonably accurate polar alignment. This can be done with the polar scope once you get close and can recognize Sigma Octans.

The first thing to do is set mount up so that the base is level and the "N' mark on the tripod pointing as close to south as you can. Then set the elevation to your latitude. Don't rely on the scale it could be 3 or 4 degrees out. Make a triangle with one angle equal to your latitude, This can be done with trigonometry and some wooden slats. Place this on the telescope mount and use a spirit level to set the elevation. Next point the RA axis at the true south. A compass is used for this but remember to allow for magnetic deviation. You may find using Google Earth to locate an object due south of your location that can be used as a sighting mark.

Once you get this close you should be able to find Sigma Octans in the polar scope. Line up the stars and then use your goto alignment procedure to align the scope.

Barry

PS forget the setting circles on the scope axes they will be too confusing for the beginner firstly the dec scale is not accurate enough and secondly the RA setting circles refer to hour angle that changes by the minute and not RA. When you get the goto working the controller will give you an accurate position display.

[willpower (Will)]

Originally Posted by Barrykgerdes

Hi Will

You did not say what the scope was but I assume from your signature it is an ED80 on a eq5 pro goto mount. Does it use the Synscan control system? Is it the Heq5 Pro with synscan

Hi Barry, thanks for your detailed advice. My scope is an ed120 and mount is an eq5pro goto with Synscan. I went out and got a compass today and will attempt my first allignment tonight. Going to rough align and not bother with the polar scope just yet. On closer inspection I found the Sigma Octans diagram in the viewer so will work on using this when I get better!

Cheers again!

Will.