Magnus,

I was thinking of the settings under options - calibration and guide.

My problem at the moment is that I don't have my camera and don't know how to bring up my settings without it.

So The gemini driver uses the Meade pulse command guiding... does Gemini support its own pulse guiding routine or is it the same as Meade?

EDIT: Ok from the documentation, it supports the same format with this note:

:Mg<direction><time># Moves into <direction> "e", "w", "n", "s" for <time> milliseconds. <time> is converted into motor encoder ticks, in L4 the result must not exceed 255 or will be cut off modulo 256.

So if you have L4, this might be a problem as anything above 255ms will be cut off

My recommendation would be to try an st4 cable to see if you get better results. I have had a Gemini 1 for about 8 years now. For years I was guiding with pulse commands and never really got great results. I used different software packages, different computer types, and still did not get good results. (Mac, Linux, PHD, PHD2, KStars, direct USB, over INDI, etc.) I had not tried an ST4 cable because my camera didnt have an ST4 out jack. I bought a ZWO ASI 120 usb3 because I thought the issue was related to pixel size. It gave no real improvement though. But about 5 months ago I tried the ST4 jack and saw immediate improvement. I got even more improvement when I started running PHD2 on a raspberry Pi stuck right on the mount so no communication or image download delays.

Thanks,

Rob

Hi!
So, after a few days of clouds, here is a log with mount driver data as well. Same behavior - wild swings in RA when guiding also in Dec. I have turned Dec on and off a few times - each time I turn it off, RA calms down, each time I turn it on, it goes wild again. Attached is both INDI, Ekos and PHD2 logs.

Magnus

Hi again!

And now I can confirm that using the ST4-cable instead seems to work nicely. No swings at all, good guiding behavior.

Maagnus

Hi!

A slight update: ST4 works, but my experience now, is that it does not work as nicely as I first said. I cannot get guding below 1", even though I previously, with Gemini 1, hade 0,6-0,7" as standard. And the experience among many Losmandy users seems to be that performance is better with pulse. However, I am going to explore this further next week (travelling this week). And if we could get the pulse guiding to work, that would be wonderful!

Magnus

Hi!

Any hope of any progress on this? Tried tonight and still same problem: wild swings in RA when mount connected through Indi, much calmer when "on-camera" But guiding quality not as good as it used to be with connection throgu Indi.

Magnus

Magnus,

I have experienced the wild swings, if you mean it suddenly slews to somewhere completely unrelated to where you want it to go - sometimes making the camera head towards the mount. I always make sure I can abort it from INDI, as I have found that when this happens the hand controller does not respond.

I have found that the best way to avoid this is to always perform a synch after a coldstart and then use align for the following slews.

I believe that it must be corrupting the model because the park at CWD still works correctly so it knows where it physically is. exactly what the problem is eludes me and is unpredictable. It means I cannot trust the mount when slewing and need to keep an eye on it. The only solution I have found is to perform a coldstart.

Hi!

No, I'm talking about swings in RA while guiding - up to 15" in swings,, killing every possibility of imaging, and seemingly triggered by pulses i DEC - when not guiding in DEC, it is smooth. And this is only when using pulse commandes, using ST4-cable works OK. See my previously posted guidelogs for a visual illustration.

Magnus

Magnus,

I am using PHD2 as the guiding program and I attach to INDI using INDI mount. I have Pulse Guding enabled and although it has an issue where it will not maintain the driver setting - reported to PHD2, it works fine.

I notice you originally said that you had no problems under Windows, but I cannot see where you mention your operating system.

I am currently running Raspbian as the Ubuntu Mate version stopped recognising my QSI camera.

In the past I have found that wild swings are generally cuased by the software trying to handle the scope being too well balanced and contimually trying to correct it. Sort of a resonce effect. You may be better off posting the question to the PHD2 forum as they have many years experience with this. I would try and unbalance the scope so it is slightly weigted east and either north or south and see if this has any effect.

Hi!

Interesting. You are using Gemini 2 as well? My setup is a R-Pi with Ubuntu Mate, where the indiserver runs. THen Ekos on a linux laptop indoors.

I have posted at the PHD2 forum, (the post and discussion is here: groups.google.com/forum/#!topic/open-phd-guiding/Pgj5utiy0NA) and after having discussed there, they concluded that it probably is not PHD2 related. It works nicely in windows with ASCOM, and OK with Ekos/INdi using ST4 - with the exact same balance and pointing to the exact same spot in the sky. I switch from pulse (wild swings) to On-camera in PHD2, and it calms down. So I figure it must be Indi-related.

So very interesting if you do not experience this. What happens when you switch from pulse guiding to ST4/on-camera? And could you perhaps post your precise Indi settings for the guide cam?

What more could I check and try....?

Magnus

I am using a different mount than you (SkyWatcher HEQ5-Pro with belt mod) and I notice a difference between pulse guiding and ST4 guiding using an RPi3 as well. The mount is connected with an EQDir cable and I am using the EQMod driver. For slewing and tracking this is great but for pulse guiding I see a deterioration in guiding in RA as well. I admit it is not as extreme as in your case (about 2" to 5" but the 5" are strange jumps with an occasional larger jump up to 10" but those are very rare). When I use ST4 guiding I get RA RMS of 0.5" and Dec RMS of 0.4" constantly. I guess the RPi3 is not powerful enough to do proper pulse guiding because of the complexity of the EQMod chip and cable.

When I use Ekos on my laptop and connect the mount directly to the laptop I get much better pulse guiding. I haven't tried lately but I think I got about 1.2" RMS in RA and about 0.6" RMS in Dec but that was before I used 2x2 binning in the guiding frames. I could try 2x2 binning and see if that reduces the RMSs sufficiently as well because it reduced the RMSs with ST4 guiding from the RPi3 as well. But since I'd like to use the RPi3 and not my laptop, I am content with ST4 guiding.

So, what happens if you try to guide directly from your laptop instead of with the RPi in between? Is pulse guiding then OK or does it jump as well?