Can you polar align using a DSLR?

[John K]

If I was to attach my DSLR to my scope (12.5") which has a field of 30' and locked the scope at 90 degrees dec, then pointed it south taking 60-120 second exposures of the SCP area and making adjustments until I could centre the star trails and SCP in the centre of frame, would that give me a good enough alignment for deep sky photography work?

Anyone tried it?

[seeker372011 (Narayan)]

Yes indeed

Alex first suggested this approach and I have been using it ever since-for at least 12 months


I get 10 minute exposures easily with a Cg 5 (autoguided of course)

[Geoff45 (Geoff)]

Originally Posted by John K

If I was to attach my DSLR to my scope (12.5") which has a field of 30' and locked the scope at 90 degrees dec, then pointed it south taking 60-120 second exposures of the SCP area and making adjustments until I could centre the star trails and SCP in the centre of frame, would that give me a good enough alignment for deep sky photography work?

Anyone tried it?

Smart idea! The only thing you would have to be careful of would be that your dec circle (or whatever you use to set 90 deg dec) is accurate.
Geoff

[xelasnave]

I think you need to eliminate cone error.
But if everything is right it seems to work to get you pretty close.
I have nights where I get so confused doing drift and you would think after all this time it would not happen but it does, time between shoots is a bit this year so that would not help.
I also take some shots on the horizon and above showing the drift left by a couple of exposures so I can look at it again the next day and figure if I was adjusting the correct knobs.
Best solution is to permanently mount the scope and mount (mount at least)so you finally dont have to worry about this part of setting up...I am nearly there and already life is better.
But you still need to finally drift align for real long runs.
alex