Losing tracking when slewing with BYE

[shbarr2001]

To support staff,

I downloaded the trial version of BackyardEOS (Version 3.1.18) a couple days ago.  I am quite impressed with the intuitive interface and thorough functionality.  I'm planning on using BYE now for camera control.  Good work everybody.

Last night was the first time I tried BYE with both camera control to my Canon 6D Mark II and my Celestron AVX mount.  I was using Focus and Frame to see my targets, or very close to them, and the slew buttons to move the mount to get the object centered.  Let me first say that I used Celestron CPWI to align my scope and then used the slew keys on BYE to center my target.  Anytime the BYE slew keys were used tracking was disabled and I went back to CPWI to enable tracking.  Is there something that I'm missing as I'd like to control my entire imaging session with BYE without having tracking disabled.

Thanks in advance for your help!

Cheers,

Steve (shbarr2001@yahoo.com)

[admin]

BYE uses the ASCOM MoveAxis command to move the mount using slew arrows.

The code below s what is used in BYE to a slew.

The first line reads the current tracking value... then it performs the move, and the finally clause towards the end (which is always executed) resets the tracking to the previous value (from line one). This should reset tracking. I'm not why your mount stays in non-tracking mode but I can confirm the tracking is being reset to ON after the move if it was ON before the move is issued.

            var isTracking = Telescope.Tracking;
            try
            {
                if (Telescope.CanSlew && Telescope.CanSetTracking)
                {
                    Telescope.Tracking = true;

                    switch (direction)
                    {
                        case TelescopeSlewEnum.Up:
                            MoveAxis(TelescopeAxes.axisSecondary, 1 * speed);
                            break;
                        case TelescopeSlewEnum.Down:
                            MoveAxis(TelescopeAxes.axisSecondary, -1 * speed);
                            break;
                        case TelescopeSlewEnum.Right:
                            MoveAxis(TelescopeAxes.axisPrimary, -1 * speed);
                            break;
                        case TelescopeSlewEnum.Left:
                            MoveAxis(TelescopeAxes.axisPrimary, 1 * speed);
                            break;
                    }

                    return true;
                }
            }
            catch (Exception ex)
            {
                LogError(ex);
            }
            finally
            {
                Telescope.Tracking = isTracking;
            }

 

[astroman133]

Steve,

First a clarification of terminology. BYE does not slew a telescope. It nudges or jogs the scope. Slewing moves the scope to a specific target. BYE's operation nudges the scope at a selected rate for as long as one of the nudge buttons is depressed. It does not have a specific target in mind. This is important because according to the ASCOM driver design documentation the driver is supposed to return to the previous tracking mode when the nudge operation ends. Apparently this is not happening. This is a problem with the CPWI ASCOM telescope driver, not with BYE.

Your exact symptoms were reported by another user a couple of weeks ago. That user stopped replying to the thread that he created, so we don't know if or how he fixed his issue. Here is his thread --> 

So you have two options. You could contact Celestron about the behavior or you could switch to the Unified Celestron driver, which is not written or supported by Celestron.

First option --- On the ASCOM web site at ascom-standards.org you can download the driver conformance testing tool, called Conform. If you run this program and connect to your scope using the CPWI driver, the generated report will highlight any issues with the driver. If the driver fails any tests, especially the MoveAxis tests, you should provide the report to Celestron who can forward it to the CPWI driver authors. Any driver author should test their driver with Conform before releasing it!

Second option --- Also, on the ASCOM web site you can download the Unified Celestron telescope driver. This driver can be installed side-by-side with the CPWI driver as long as you only use one driver at a time to talk to your scope. This driver behaves correctly with regard to restoring the tracking state after MoveAxis calls.

[astroman133]

Guylain,

You should not need to mess with the tracking flag in BYE. MoveAxis should work just fine whether Tracking is on or off, and when the button is released the ASCOM driver should automatically resume tracking or not (just what you are doing in your provided code). If BYE does not set or clear the Tracking state, then it cannot be the cause of tracking being turned off or not turned back on after one of the move buttons is released.

The following sentence was copied/pasted from the ASCOM Developer Help file in the Remarks/NOTES: of the MoveAxis method definition:

        When the motion is stopped by setting the rate to zero the scope will be set to the previous TrackingRate or to no movement, depending on the state of the Tracking property.

The driver must provide this behavior. You will drive yourself crazy and pollute BYE's code base if you try to make BYE tolerant of drivers that do not comply with the ASCOM standard.

One final thing occurred to me when I looked in detail at your code...What happens if the driver itself, or another connected application, changes the tracking flag while a move is occurring? BYE could then be restoring the tracking flag incorrectly in the finally clause.

 

[admin]

45 minutes ago, astroman133 said:

First a clarification of terminology. BYE does not slew a telescope. It nudges or jogs the scope. Slewing moves the scope to a specific target.

This is true up until 3.2.0 pre-release, where telescope slew was added, along with plate solving, in the Premium Edition. But for the current production 3.1.18 the above statement is still accurate.

[astroman133]

Thanks for the correction. I have not seen the pre-release version yet.

[shbarr2001]

Actually all I was doing was nudging the scope rather than slewing.  Sorry for the incorrect nomenclature.  Right now I think the simplest method would be either to use the CPWI hand control or the unified Celestron Telescope Driver.  In any case, I'm planning on purchasing the premium version of BYE since the functionality for camera control exceeds others I've tried.  Not sure of the timeline on the above comments, so I'll ask if version 3.2 has been released?  If it hasn't, will I get free updates?  In any case I'll probably continue to use CPWI to slew to a target and then only use the nudge buttons (when I correct the problem) on BYE to center the target.

Thanks for the prompt response.  I'll post another reply if I get more info.

Cheers,

STeve

[admin]

3.2.0 is in the pre-release download section.

I have not charged a dime for upgrades in 10 years.

Regards.

[dkerber]

IIRC, there have been questions on teamcelestron.com (the place where the CPWI and Celestron firmware developers hang out) about some mounts not properly reverting to their previous tracking status after some commands. I don't recall if that's fixed yet or not. It doesn't happen with my CGX-L, so I don't follow the issue closely; just saw it in passing. You might visit there if you want more news and information on this. You can also get betas of CPWI and help steer the development too...