Polar alignment software

[malc-c]

I've been googling all evening and lost for a possible solution for tweeking the polar alignment for an observatory based HEQ5 mount

I use the alignment tool in EQMOD, which rotates the mount to the HA for Polaris, but there are two factors which allow for a "near enough" rather than a "spot on" adjustment.

• The circle in the polar scope in which to place Polaris is huge compared to the star you are placing in it
• The actual position of Polaris now compared to when the polar scope was made has to be taken into consideration, and is a "best guess" on how to place Polaris 

The issue I have is limited views to the East and West, so where most drift alignment routines fall over for me is selecting suitable stars low enough down on the Eastern / Western horizon to drift align correctly.  I did try Alignmaster, but we never got on and it actually made the PA worse than it was before messing about with the program.  I have PHD2 and that looks easy to follow, but again I think I'm going to be dissadvantaged due to the poor E/W horizons.  I have CdC installed, and access to C2A and APT, although my Canon doesn't have live view.  I do have an QHY5 which can be used with the 200P explorer scope should a live view be required.  Given this software I beleive plate solving is not possible, but then plate solving is a bit beyond me at the moment.

Any suggestions for a suitable, ideally freeware or low cost, appliaction that can work with either a QHY5 or DSLR camera (no live view as mentioned), with CdC etc.

[Tinker1947]

The handset should have a PA routine that uses any star from a scrolling list, this should show up after  a 2 star align, in the same section, run this a couple of times on different stars, then switch back the EQMod and test the unguided times....works on my NEQ6....

[Snaxmuppet]

Take a look at Alignmaster. This is perhaps the most accurate way without drift aligning and it can be as accurate as drift aligning if carefully done (1 arc minute) and certainly more accurate than a polar scope. Once again, once you have done it a couple of times it is pretty quick and easy. There are a number software options... see here for some choices : http://www.thewilmslowobservatory.org/polaralignmentsoftware.html

There is a great video by Astronomy Shed on using AlignMaster.

 

 

BTW I find these Astronomy Shed videos superb. He has a great way of explaining the practical aspects without getting bogged down in unnecessary detail.

[malc-c]

Take a look at Alignmaster. This is perhaps the most accurate way without drift aligning and it can be as accurate as drift aligning if carefully done (1 arc minute) and certainly more accurate than a polar scope. Once again, once you have done it a couple of times it is pretty quick and easy. There are a number software options... see here for some choices : http://www.thewilmslowobservatory.org/polaralignmentsoftware.html

There is a great video by Astronomy Shed on using AlignMaster.

 

 

 

BTW I find these Astronomy Shed videos superb. He has a great way of explaining the practical aspects without getting bogged down in unnecessary detail.

I had tried that as mentioned in my post.  for me it messed my alignment up more than it was before I used it.

[malc-c]

The handset should have a PA routine that uses any star from a scrolling list, this should show up after  a 2 star align, in the same section, run this a couple of times on different stars, then switch back the EQMod and test the unguided times....works on my NEQ6....

Sorry, should of mentioned - I have no handset - I use EQMOD to control the scope

[Snaxmuppet]

I had tried that as mentioned in my post.  for me it messed my alignment up more than it was before I used it.

Sorry... missed that you had tried it (Note to self... read the detail twice before posting!). Not sure how it messed you up tho. Basically, it works. I found that video worth watching.

Software is very personal. Some people love a certain package while others don't get on with it. Might be worth trying one of the others. Something else might work better for your situation... they are all coded differently.

Good luck.

[Tinker1947]

Sorry, should of mentioned - I have no handset - I use EQMOD to control the scope

I use EQMod to GoTo,but have the handset also, for me swapping the plug over do the alignment via the PHD screen (don't use the Polar Scope) make for a accurate PA, if you don't have a Handset then you should get practicing with  Alignmaster i would think you could play about in the daylight getting the setting right....you have nobody closeby you could borrow a handset from.....

[martin_h]

Might be worth a look ................... http://eqalign.net/e_eqalign.html

[Dave_D]

• The circle in the polar scope in which to place Polaris is huge compared to the star you are placing in it

i used to use alignmaster but it's rubbish at selecting target stars if you don't have 360 degree clear views (well, it was for me anyway).

i just use ascom routine now, plus a carefully aligned polarscope.

small trick, defocus polaris to a blob slightly smaller than the reticle circle, makes centering it a doddle.

[malc-c]

Martin, thanks for the link - I'll take a look later.

Dave, nice tip for centring polaris in the circle on the polarscope recticle - However due to precession Polaris is now no longer in that circle - EQMod now has an updated PA tool to reflect the difference (as can be seen in the image below)

[Gonzo]

have a look at this tool:

http://stargazerslounge.com/topic/229902-looking-for-beta-testers-of-new-polar-alignment-utility/

[malc-c]

Gonzo, thanks for the link,

I've asked a couple of questions on that thread as I'm easily confused   - but it sounds easy to use and people were getting good results

[Earl]

Have you tried drifting with PHD2? it might be worth a punt even with limited horizons

[wxsatuser]

I use PHD to drift align and use a star more than 20degrees above the horizon to the East.

If the star is still near 0 degrees dec it will be slightly further to the south east but it still works ok.

[Dave_D]

Dave, nice tip for centring polaris in the circle on the polarscope recticle - However due to precession Polaris is now no longer in that circle - EQMod now has an updated PA tool to reflect the difference (as can be seen in the image below)

well that just shows how long it is since i got to use my scope :/

[malc-c]

Earl, no I haven't tried it, but might give it a go next clear night.  - Have tried the application Gonzo suggested and getting errors / issues with python... so not off to a good start, so PHD might be the alternative option

Mike, that's worth noting... I'm not 100% sure what's the lowest angle above the horizon I have due to trees and a large hedge, but I'm guessing it can't be more than 25 degrees.

Dave, I think you'll find it will be the same for SW scopes purchased today... guess they produce the reticles by the millions and still have stocks left

[Earl]

make sure your flattening the correct line then double check, catches me out every time LOL

[wxsatuser]

Earl, no I haven't tried it, but might give it a go next clear night.  - Have tried the application Gonzo suggested and getting errors / issues with python... so not off to a good start, so PHD might be the alternative option

Mike, that's worth noting... I'm not 100% sure what's the lowest angle above the horizon I have due to trees and a large hedge, but I'm guessing it can't be more than 25 degrees.

Dave, I think you'll find it will be the same for SW scopes purchased today... guess they produce the reticles by the millions and still have stocks left

I gather that as long as the star is within 5 degrees of zero dec it won't make much difference.

The further you move from zero dec the more error you may incur.

I have confirmed this method with very long DARVs.

I get very straight lines with 10minute DARVs so I leave it at that.