Advice on Polar Alignment

[Rockrae78]

Hi all,

Not sure if this is the right place to post this... mods feel free to move it! 

I have a Celestron CPC 800 and heavy duty wedge. Only tried polar aligning twice, and on the 2nd go, I think I cracked it (sort of!). Followed all instructions and when I finished, I chose a few targets, and each one was bang on centre in the eyepiece. 

The final instruction was to check the polar alignment errors. The errors were displayed as:

Azm: -00^o 04' 10"

Alt: -00^o 00' 02"

I have no idea what this means!!! Is this good or bad? Any advice would be appreciated. 

Rae

[knobby]

Its how far away from being perfectly polar aligned the mounts software thinks you are ...Azm right left at up down

[Rockrae78]

Ok... Thanks for that! Much appreciated! 

So the bigger error is the azimuth then. Not surprising seen as getting pointed exactly right to "True North' is proving impossible with compass on phone. It has a selection for both true and magnetic north, but they are so close together that I think that the app is rubbish! 

My next question is if this is in acceptable limits? It's less than a degree. What would be unacceptable for errors (i.e. how big of an error would be worthwhile me doing it again)?

Rae

[knobby]

Are we talking imaging or visual ?

[Rockrae78]

Either. Both. i'm just asking because there doesn't seem to be any advice as to how small the error should be. I mean, what is the maximum error you would cope with? What size of error would make you stop and do the polar alignment again? 

I'm mainly a visual observer. I've had a couple of go's at taking planetary images, but I don't really think I've got the patience for proper astrophotography. But it would be nice to know I'm on the right track should I ever want to go down that route! 

[knobby]

From my limited DSO experience 4' would be fine if guiding but maybe try for better if unguided.

Best bet would be to try a 30 second exposure and have a look

[Rockrae78]

Thank you!! That helps a lot! 

[knobby]

No worries, how did you try planetary ? Webcam ?

[Rockrae78]

Yeah, I've got a really naff Celestron Solar System Imager. It's proper pants. It's a really old one.  I tried taking a pic of Jupiter and Saturn about 18 months ago on my NexStar 130SLT and both were really rubbish. Couldn't get proper focus and the mount really, really wobbles. Now that I've got a bigger and better scope I was thinking about trying again. I know the camera is rubbish, but I really can't afford to buy a better one, and as I said, I'm more of a visual observer anyway, so it's probably not worth the investment for me. 

Because I've always had Alt-Az mounts, I just don't know anything about polar aligning. I received a wedge for my birthday last year in July (probably because my OH likes photography), but I've not had the time to spend to try and get to grips with it (and of course, when I did have time, the weather was pants!). I just thought I'd give it a go whilst the skies are clear. Its a very long, drawn out process and the instructions in the Celestron manual are about as clear as mud. But, think I've got it now. Totally not worth setting up for just visual use though. 

[knobby]

Keep at it, you never know what can come out ... The video in screen can look terrible but after stacking sometimes you can surprise yourself

[Rockrae78]

I did try, but honestly, they were very, very bad! 

I will try again at some point, but when I have less stuff going on!