SharpCap Forums

I'm using phd for guiding. What should I expect from fair to good to excellent polar alignment? When I get on excellent, as soon as I tighten the mount down it goes from excellent to good. Is this ok for guiding or should I always work for excellent?

Up to about a week ago I used a iOptron phone app and polar telescope to align my CGEM for imaging. I could reliably get 3-4 arc minute alignment accuracy starting about one half hour after sunset. I recently started using the PA feature in SharpCap Pro to achieve alignment accuracies of 20-25 arc seconds! The only downside is that I need to wait until about an hour after sunset to get a high enough star count in my guide scope using a LodeStar camera.

I am seeing that the improvement in PA does not necessarily translate in significantly better PHD2 tracking in terms of rms tracking error. The better PA results in fewer guidance updates but it appears that that seeing conditions dominate the tracking errors.

BTW I am very impressed with the SharpCap PA and will continue to use it for my alignment.

Hi,

glad you are enjoying the polar alignment feature. Do remember to set your lat/long in the settings and enable the refraction correction feature which will improve alignment further. You could also try using the digital gain control for your Lodestar camera to see if that helps pull out enough stars during the earlier part of twilight.

cheers,

Robin

I plan on using the Lodestar as well for my polaralignment routine, but noticed that the Lodestar has non-square pixels. Will that affect the result? Obviously you did get it to work.