polar alignment frustration eq2

[Sean L]

hi, I know this has been asked more times that there are stars but I'm having huge problems and it's driving me mad. Iv got an eq2 mount and I just can't for the life of me stop the stars drifting even at after a few second exposure on my camera. Please someone tell me what I'm doing wrong. I face one of the legs on my mount north towards polaris then make my my whole scope straight as I can towards the north also. I then adjust the latitude to 52 degrees as that is where I am... Now when I look through my red dot finder it is still miles underneath polaris. Are the numbers on my scope wrong?! Or should I change my latitude to 70 degrees (which I need to get it spot on polaris) iv got a motor drive too but that doesn't seem to steady things so my alignment must be wrong... Please help, thanks

[Cornelius Varley]

First thing to check is that your RDF is correctly aligned with the main telescope. Point the telescope at something in the far distance and then adjust the RDF so the the target is centred on the red dot. 

[Sean L]

My rdf is perfect if I point it at a star it will be bang on in the middle of my eyepeice

[bogdog]

My rdf is perfect if I point it at a star it will be bang on in the middle of my eyepeice

can only suggest you havent got polaris picked out correctly then?

if whatever you select with rdf is also in viewfinder

[Sean L]

That's occurred to me to then I asked other people to point it out so so I knew I wasn't going crazy, could the latitude degree numbers be wrong because they are just a sticker. I am right in thinking that it the scope is pointing north and my latitude is correct then I should have polaris in my eye piece?

[bogdog]

if all points nrth and you have polaris in viewfinder then i would simply ignore the lattitude scale for now and try another exposure,see if you get drifting

search for a topic on drift alignment,in one i read it suggested how to do this and if a star drifted one direction you adjusted scope lat to compensate

eventually repeating the process until everything worked out?...never tried myself so cant advise any more on that

[bogdog]

found the link i read..

http://www.backyardastronomy.net/drift_alignment.html

[Sean L]

Thanks guys going to give it a try, cheers

[ronin]

Why should Polaris be in the centre of the scope?

It is the mount that is aimed at Polaris not the scope, the idea is to point the mount at Polaris and align the mount with the earths rotational axis but point the scope at other things like Orion Nebula that is not overlaying Polaris.

You shouldn't need a scope on the mount to polar align the mount if you think about it.

[Pint Of Stellar]

This youtube clip helped me to understand more the situation with polar/drift alignment - bear with it and keep your head clear and it makes a lot of sense.