ASPA - how good is it?

[Thalestris24]

Hi

Would like to hear from any celestron (VX) mount owners who use the built-in all star polar alignment. How versatile is it? How accurate is it when using just one star? Can you use more than one star on one side of the meridian? I have a limited view of the sky which is either due east or due west, making PA difficult (I have to do a lot of trial and error!) so was wondering whether the VX ASPA would make life easier - or not!

Cheers

Louise

[Thalestris24]

Anyone?

[knobby]

Haven't tried it yet :-( but from what I've read, it's very good but you do need to do a 3 star align and add a couple of calibration stars to get it accurate.

Not much help , but better than no reply ;-)

[Thalestris24]

Haven't tried it yet :-( but from what I've read, it's very good but you do need to do a 3 star align and add a couple of calibration stars to get it accurate.

Not much help , but better than no reply ;-)

Hi Knobby

Thanks for the reply!

Louise

[knobby]

There's a lot of info on cloudy nights , they seem to really rate the AVX over there

[Thalestris24]

Oh ok - might have a squiz there. I'm just half-thinking about a second mount but I have a very restricted view of the sky - through my flat windows!! So, can only see a small amount of the sky and only either east or west. Polar aligning is challenging and involves lots of iterations!! I don't suppose there is any magic involved with the VX though it does have encoders and a much better altitude adjustment compared to my Heq5 Syntrek. It's also a bit more expensive...

Cheers

Louise

[Kirscovitch]

Love my VX. 2 star align with up to 4 calibration stars. The ASPA is pretty simple. Choose your star and the mount slews to it. Center it in the ep and hit enter. Mount slews away at the amount of PA error you have. Use the knobs to bring the star back to center of EP. Then you can check your error of alignment with the handheld.

I usually do mine at least 2x and sometimes 3 times for greater accuracy.

The best alignment I had with it was able to go 90 second subs un-guided. 

[Thalestris24]

Hi Matt

Ok - thanks!

Louise

[orion69]

I used ASPA on my (now sold) CGEM and routinely shot 30 min subs @ 765mm fl.

If you want decent accuracy I recommend using crosshair eyepiece or camera with crosshar screen,

2+4 stars and polar alignment after that. Usually you do not have to repeat the process (I never did).

[Thalestris24]

I used ASPA on my (now sold) CGEM and routinely shot 30 min subs @ 765mm fl.

If you want decent accuracy I recommend using crosshair eyepiece or camera with crosshar screen,

2+4 stars and polar alignment after that. Usually you do not have to repeat the process (I never did).

Hi Knez

30mins unguided is pretty awesome! I'm not sure I could use the ASPA though as I can only see east as I use my gear from inside my flat. I wonder what choice of PA alignment stars there is? The VX looks a very good option though. Maybe I could set it up outside then tweak it from inside my flat?

Thanks

Louise

[Kirscovitch]

I have used Vega before for ASPA and didn't seem to have a problem with it.

[Thalestris24]

Hi Matt

Reading through the VX manual it does say that a calibration star has to be on the opposite side of the meridian to alignment stars. Bit of a bummer if you can't see the other side of the meridian...

Louise

[Kirscovitch]

Was pretty pleased tonight with it

190 sec dubs and minimal trailing.