In EQMOD it is possible to move the mount to the position of polaris and than adjust the azimuth and elevation of the mount.
It would be nice to have similar function.
Another thing that could help is a drift align like in phd2.
It is not always easy to find stars close to south horizon close to meridian or west star well placed to use the astrometry polar alignment.
In fact it would be nice to marry those two functions with astrometry polar alignment to have a complete toolbox for this process available in Ekos.
I vote for this ! Having such feature would avoid me to boot on windows to use the EQmod polar align feature.
I addition, I recently discoverd the QHY Pole Master (qhyccd.com/PoleMaster.html). There is currently no Linux drivers for this. I don't know what the hardware used is, but having it working with kstars would be great ! It seems to allow a very precise polar alignment in a few minutes.
I vote for this also. I am using the polar align help from EQMOD, and i would like to get the same on Kstars or somewhere in the INDI environment as i can use it on a Raspberry and i would not be obliged to bring the laptop for this very first step.
Doing what polemaster does should be fairly strait forward with any camera. The crux of the process is this.
- slew to pole
- Take one shot
- Leave Dec at 90, slew 45 to 90 degrees in RA
- Take another shot
Solve both fields. From those solutions, you can calculate where the center of rotation is, and where the pole is, they are likely on different pixels in the shot. Now adjust the mount so that the center of rotation and the pole co-incide. Voila, perfectly aligned.
This is one program on my 'to-do' list that I haven't got to yet, I did use something similar a few years ago where we had the displays running live from the qhy5 in the 9x50, and after taking the two shots, program calculated the pixel corresponding to the center of rotation, and the offset from there to the NCP. Then it would draw a circle around one of the stars in the shot, and draw a cross hair on the screen where that start needed to move. With short / fast frames coming from the camera, we could then adjust the mount and see in real time on the display where the star was, and where it needed to be.
After one iteration, we usually would have polar alignment within a small handful of arcseconds, ie, down to the resolution of the camera.
3Oh, thanks for these details, and it would be great to have this sure, but my request was for more simple topics, the small help like with EQMOD :
"In EQMOD it is possible to move the mount to the position of polaris and than adjust the azimuth and elevation of the mount."
I am trying to make the transition to Indi from Windows and I currently use a QHY Polemaster - it just works (5 minutes tops, from scratch) - and is well worth the investment.
So this is on my critical path and I would vote for an 'Indi Polemaster'. As Gerryr says, I think its not that difficult in principle, and I see QHY cameras are currently supported. So I suspect it would be a capture-and-solve routine sitting as a standalone utility under Linux?
For those of us that do not have a clear view of Polaris, there is a polar alignment procedure, using plate solves,by imaging at the meridian for RA corrections and towards the east for dec. The procedure is very similar to what you have implemented; image, solve, move the scope, image again, another solve and then calculate the error in pointing. Show the error on the screen and use that to adjust the scope to point to a given star.
Is there any chance you might implement this process as well? the process is described here: