Greetings,

Currently using Ekos/Kstars and Indi server on an RPI, as seen here:
.
In the Windows version of Eq-mod, you can set some mount limits as in eq-mod.sourceforge.net/docs/EQASCOM_Limits.pdf

Are there any plans in adding this feature to indi_eqmod please?

Regards
Stephane

Hi Stephane,

I think I will have a look to this feature during this summer. I just read the document you point out. Do you think that using the CDC file format would be a good choice for saving horizon points list ? In this way the indi driver may remain simple as it won't manage the list itself, just a filename. Users may use a simple editor (or CDC itself ) to edit their horizon points.

Regards,
Jean-Luc.

geehale, you can even save the limits as a fits image if you like, in the form of a 'mask'. I've worked for example with all-sky cameras and this procedure is quite common, to generate a 'mask' in ALT-AZ filled with 1 and 0s.

Hi Jean-Luc,

I was thinking more like having it in the eqmod indi control panel, similar to the park feature where you can write the coordinate of the current mount position to a file.
Something like:
a section called "Mount Limits"
RA| min: set (enter value) ~ write current position to file
RA| max: set (enter value)~ write current position to file
DEC| min: set (enter value)~ write current position to file
DEC| max: set (enter value)~ write current position to file



Regards
Stephane

Hi Jean-Luc,

Would you have any news on this please?
That would be a real added bonus.


thanks a lot

Stephane

Hi Stephane,

I started to think (and read) about mount limits, and wanted to perform some tests using client-side software. My first concern was horizon limits and I wrote a shell-script (together with a python script which does the same) that polls periodically the mount for alt/az and eventually abort it if it reaches limits (based on a simple interpolation from a list of points stored in a file 'a la CDC/Skychart'). This could be used for stopping the mount during a capture session, but while performing a goto, you go away by 20 degrees or so with a polling interval of 2 sec. It could be enhanced by computing (or getting) the actual axis speeds and aborting the moves before it reaches the limit, but this could be very complex. Knowing that, the driver has a polling interval of 1sec, and thus would have to perform that sort of computations. But if we consider it is knowing goto targets and horizon limits, it can forbid such outside gotos. Now what about free moves ? The simplest would be to leave them unlimited. So my question is if horizon limits should'nt be managed by client-side software: planetariums use horizons and they can limit your gotos based on that (after all, you perform all of your gotos from a planetarium). And a small monitoring software can be used to stop a capture session, moreover it can abort your CCD exposure before stopping the mount. Last but not least, that could work for any kind of mounts.
The second point concerns around zenith limits and/or collision with tripod when tracking without performing a flip. At the moment there is no detection in the driver of such 'hardware' limits. I 'm currently asking myself if there is a way to compute a sort of slewing enveloppe based on simple measurements of the equipment., but that's another point. Perhaps the driver could consider a circular zone around the zenith and forbids it. And it could also abort moves after the meridian has been reached. I could add some properties to parametrize these two limits.
By the way, from what I read, it seems that all this has already been greatly discussed for other softwares, but i am unable to find the best apporach if there is one.
So any suggestions are welcomed.
Regards,
Jean-Luc.

Thanks for looking into this Jean-Luc, much appreciated.

I'm going to test AstroEQ on my Windows XP partition and check out how the limits on eqmod works.
Will see I can come up with a plan.

I've tried the mount limits in eqmod (Win version) yesterday, and wow it's rather good.
I do like the fact you can set as many limits as you want.

Just thought about something awesome but also mega complicated at the same time .... lol
Let's just say mount limits are implemented, how cool would it be when you start Kstars that is shows on the map where you can point the telescope to?
ie: when you look at the map, an overlay of the "free slew to zone" is being displayed.


I'm going to start thinking of a script too, would you mind sending me your script please?
I think you have my email address already.


thanks again for looking into this, it is something that I believe all Kstars/Ekos users would love to have.
While I'm still testing the all thing before I go live with my remote observatory, I had some near misses (crash on tripod legs) which I was able to stop on time.



Stephane

Hi,

I commited a version of indi-eqmod with Horizon limits (together with some backlash compensation which I did before). This is a simple PointList version: you could manually add points giving Az/Alt or slew your scope to desired points and add them with "Add current scope" or directly edit a file containing a list of points (with a syntax similar to the one of SkyChart, except that Az coords may be floating numbers here) and load it manually. There are options to abort Tracking/Slewing/Goto when Horizon limits are reached (by default only Tracking will be aborted), and to limit Gotos (enabled by default). I planned to build a fits image from the PointList but this is not yet implemented (the Display Blob should not be there actually) and I wonder if I will do.

Give me your feedbacks as I do not have much time to perform strong tests. I just noticed that when trying to slew to a star near the horizon, it gets out of mount limits when it is 14 arcmin above horizon in kstars. There may be a slight difference in Az/Alt computations. Or refraction perhaps?
Regards,
Jean-Luc.
PS: I join a simple Horizon file in attachment.

Thanks for this, I will definitely test it this week as I have now arrived in Germany where I will assemble my observatory.
Will report of any issues.


Stephane

deleted. I was being a n00b for the compile.... doh