iOptron CEM40/ASIAIR Autoguiding Problems

[Herrman]

Hi,

I’m not sure if this would be best posted as a Mount or Software problem, but here goes:

I purchased a secondhand CEM 40 some months ago, it looks as new, and I’ve no reason to believe it’s not in good working order. It slews and Go-To’s fine.

I’ve experimented with autoguiding using with a EQ80/lodestar combination, which after a few problems appears now to be working well.

However, when I try guiding using ASIAIR/Evoguide50/ASI120MM, the results are disastrous- the mount’s performance is more stable unguided!

The mount is polar aligned using iPolar. The imaging scope is a RedCat51 c/w ASI1600/EFW, which is well-balanced.

I’ve tried adjusting exposure and aggressiveness values, but to no avail.

Any thoughts on what’s going wrong, and how to improve matters would be very much appreciated.

Best, Herrman

[PaulE54]

OK here are a few questions to try to get a clearer view.

Did you try the EQ80 / lodestar with ASIAIR? If not what guiding software and hardware did you use when things were "working well"?

It would be useful to see some sample guide graphs so we can see exactly what kind of "disastrous" we're talking about.

Does the guiding software in ASIAIR produces logs like PHD2 does? If so the logs may give clues.

Good luck

Paul 

[Herrman]

Hi Paul,

Many thanks for your swift response.

Sorry, I didn't make that clear- EQ80/Lodestar control was using iOptron's Sky Commander/PhD2.

I can post the logs for this combination, but can't find how to access the ASIAIR logs.

When I say disastrous; the curves fell of the bottom of the screen!

Best, Herrman 

[PaulE54]

Hi Herman. 

Sorry not checked the forums for a few days. I've been having similar but intermittent problems with my CEM40 and PHD2. In my case it looks like it was an intermittent problem with the USB cable to the mount. So PHD2 was sending lots of corrections to the mount but none of them were being received and the mount was getting more and more off target. Hopefully an easy fix. 

We're not going to learn a lot from the logs of the combination that was working. I don't I'm afraid know much about the guiding software in ASIAIR - I think it may be a variant of PHD2? A quick google re location of guide log files for ASIAIR says "look in the usb drive under log folder, use the phd2 log viewer to examine the log file."

From what you say it sounds like the mount may not be responding to guiding?

Paul

[Herrman]

Hi Paul,

Very many thanks for your thoughts. Apologies for the delay with responding, I also forget to check the forum and the days just roll by.

Yes, the mount appears to not be responding to guiding commands from ASIAIR. This device does use a version of PHD2. I noticed that it does calibrate very quickly in comparison to the time taken by my EQMod/PHD2 setup (although in this case it's an EQ8 being calibrated), which makes me wonder if the calibration process is to blame.

I operate ASIAIR without a USB attached so, perhaps this is why the logs don't appear to have been stored. I'm using a first generation device, although it's been update to the latest software.

I've tried a number of USB cables without improvement.

It's all a bit of a mystery, I can't decide if the problem is with the ASIAIR or the mount. I had hope that someone, somewhere worked with the same combination and recount their experience.

Thanks again for your help.

Best, Herrman

[JonCarleton]

I had horrible guiding results with an iOptron GEM28 that ended up due to a polar alignment problem related to iPolar.  Run the Guiding Assistant in PHD2 and see if it agrees with the polar alignment.

The problem, in my case, was the initial calibration of the IPolar software was way off, so it reported aligned when it was not at all.  I polar aligned using a different method and the problem vanished.  Later, I recalibrated iPolar and life is now grand.

Edited April 13, 2022 by JonCarleton

[Herrman]

Hi Jon,

Many thanks for your thoughts, which have just read.

That's very useful to know, and I will investigate. One thing worth mentioning though, is that ASIAIR Go-To/Plate Solve is working perfectly- the object of interest is always dead centre in the field of view, I'd image this would not occur if the polar alignment was way out?

I've tried to find the AIRAIR guiding logs- still without success, but what I did stumble upon was the 'Auto Restore Calibration' button, which was active. I wonder if this is the source of my problem? I had been surprised at the speed at which guiding commenced- calibration can take  a couple of minutes when working with EQMod (or GSS) and PHD2. I've  disabled  Auto Restore, not had chance to put the hypotheses to the test, but with clear skies forecast for the Easter weekend, I shouldn't have to wait too long.

Thanks again. Best, Herrman

 

[michael8554]

Hi Herrman

Yes if you don't have a permanent setup, or disassemble at the end of each session, you will need to Calibrate every night.

ASIAir similarity to PHD2 may mean the logs are in a folder called PHD.

Or use the Windows File Search facility to find any files that include GuideLog in their filename.

Michael