Polar Alignment

[abodee2]

Hi there,

I've been watching and reading a lot of tutorials on how to accurately polar align my scope and one thing that i've noticed different between my mount and all the tutorials is that the tutorials all have a small circle to align polaris in the polar scope. When I took a closer look through my polar scope I couldn't see this and I'm not sure what to do or if am i missing something? I've attached an iphone image of the view through the polar scope on my EQ5 

thanks,

A

[Gazabone]

There's a few ways to polar align but you might find this the easiest,

http://myastroimages.com/Polar_FinderScope_by_Jason_Dale/

Jason has developed an app to show where Polaris should be on your polar scope at the current day/time. The beauty of it is, is that it automatically accounts for your position relative to your meridian, day light savings (or not), date and time.

[Alien 13]

I might be wrong but I think you have the new style polarscope, the whole purpose of alighning is to determine where Polaris is in relation to the NCP i.e. its position on the circle during its rotation it looks like the new version has made things easy so all you should need to do is find the polaris hour angle (stellarium or similar) and rotate the RA axis until it matches the time inscribed on the graticule.

Alan

[Davey-T]

Just rotate so 0 is at the top then adjust AZ and Dec to put Polaris in the circle as shown in a polar app or use Stellarium and reverse the position, bear in mind that this is OK for visual and short imaging subs but needs refining for any long subs by drift aligning.

Dave

[abodee2]

Just rotate so 0 is at the top then adjust AZ and Dec to put Polaris in the circle as shown in a polar app or use Stellarium and reverse the position, bear in mind that this is OK for visual and short imaging subs but needs refining for any long subs by drift aligning.

Dave

 Hi Dave,

What do you mean by short subs? ~30s? I'd like to start off easier and image the bigger DSO's first before learning drift alignment. Would i need to do drift alignment for imaging the brighter objects that probably don't require as long an exposure? 

[Donkeiller]

There's a few ways to polar align but you might find this the easiest,

http://myastroimages.com/Polar_FinderScope_by_Jason_Dale/

Jason has developed an app to show where Polaris should be on your polar scope at the current day/time. The beauty of it is, is that it automatically accounts for your position relative to your meridian, day light savings (or not), date and time.

Something could be wrong here. When I tried to open this Polar App download, my anti-virus immediately reported it as a threat and deleted the whole file.

[glowjet]

Try Jason Dales original Polar finder program and see if there is any info on the Polar App download. It is an extremely good program and will show you the current position of Polaris on its travels round the NCP at any time of the day/night 

[Davey-T]

 Hi Dave,

What do you mean by short subs? ~30s? I'd like to start off easier and image the bigger DSO's first before learning drift alignment. Would i need to do drift alignment for imaging the brighter objects that probably don't require as long an exposure? 

Depends, if you're using your camera and a wide angle lens you may be fine, depending also where you're imaging as the lower down the faster the stars move, for any sort of telescope mounted imaging then the better you can get PA'd the less work your guiding will have to do. Your scope is f/5 I think so reasonably fast, the actual mount will have errors no matter how good you get your PA.

Do you have a guide camera ?

Dave

[abodee2]

Depends, if you're using your camera and a wide angle lens you may be fine, depending also where you're imaging as the lower down the faster the stars move, for any sort of telescope mounted imaging then the better you can get PA'd the less work your guiding will have to do. Your scope is f/5 I think so reasonably fast, the actual mount will have errors no matter how good you get your PA.

Do you have a guide camera ?

Dave

Hi,

No i dont have a guide camera, just the scope and mount with goto. I'd like to get some experience with things before looking into a guiding system 

[Davey-T]

You can try the Darv method using DSLR to Polar align, it's described over on Cloudy Nights forum, did have a link but lost it, will try to find it.

Dave

[Davey-T]

There you go

Dave

http://www.cloudynights.com/page/articles/cat/articles/darv-drift-alignment-by-robert-vice-r2760

[Casus belli]

Something could be wrong here. When I tried to open this Polar App download, my anti-virus immediately reported it as a threat and deleted the whole file.

That happened to me too.  Are you using norton?

[Scorpius]

Just rotate so 0 is at the top then adjust AZ and Dec to put Polaris in the circle as shown in a polar app

Dave

I thought the mount's adjustment knobs were called altitude (Alt) & azimuth (AZ) & the tracking axis are called right ascension (RA) & declination (DEC). But you said use AZ & Dec to put Polaris in the circle so are the terms interchangable meaning it doesn't matter which ones are used?

[Davey-T]

I thought the mount's adjustment knobs were called altitude (Alt) & azimuth (AZ) & the tracking axis are called right ascension (RA) & declination (DEC). But you said use AZ & Dec to put Polaris in the circle so are the terms interchangable meaning it doesn't matter which ones are used?

Dec is the angle from your position to Polaris marked on the scope so you adjust the altitude to alter the dec angle so basically the same thing, just use the knob that raises and lowers the polar axis and moves Polaris up and down in the Polar scope.

When the mount is guided the guiding software will adjust the declination motor to follow a star when it moves  north or south to compensate for mount errors, this is obviously not the same thing as adjusting the alt knob when polar aligning

Dave