albeltrang73 wrote: Hi
I just saw Ekos and K-Stars and find it to be a very powerful suite for astrophotography. For several years I've been using Sequence Generator Pro in Windows 10 and Ekos seems to be a strong performer as well, with the added benefit of being cross-platform. You can see my gallery here, including one image awarded as Astronomy Magazine Picture fo the Day: www.flickr.com/photos/alfredo_beltran/
I'm located at Bogotá, Colombia at 4.8 degrees north latitude and it's hard to be able to see Polaris from here (sometimes you can). I watched the video of the Ekos polar alignment assistant tool and it makes very easy to have a strong polar alignment as long as you can see Polaris.
Can this assistant be used to polar align your mount when you cannot see Polaris?
Thank you very much for your help,
albeltrang73 wrote: Hi Jo
That’s a very good suggestion.
In fact I have a wide FOV because I use hyperstar with a C925 EdgeHD and a DSLR, so I can have several degrees of sky covered in one shot.
The issue is that Polaris is very low here, at roughly 5 degrees above the horizon and isn’t always seen because of clouds. Besides, I suspect the apparent position of the refracted pole would cause alignment errors.
That’s why I prefer an alignment method that doesn’t require direct watching Polaris, if possible.
albeltrang73 wrote: Thanks Gilles
How big would be the error with this approach?
El Corazon wrote:
Generally, the closer your chosen alignment star is to the pole the smaller the alignment error should be in the end because of the earth's rotation between measurements and mount adjustments. The largest error would result if you measure near the Zenith in your case.
Does that make sense?
Edit : i think i've found
Polar assistant can be done only with declinations between 60° and 90°
Otherwise solver will fail each time.
This limitation is certainly to make polar assisant go faster, but it might be increased somewhere for specific locations like you