Regression in 3.1 HF1 - Sequence starts with a meridian flip

[Oleg Ignat]

I upgraded to 3.1 HF1 and can no longer run automation normally. As soon as my sequence starts, it pops a meridian flip dialog and tries to do a meridian flip. My target is very far from meridian. Instead of executing a slew to the target, it pops a meridian flip. My starting position of the sequence is home, pointing to polaris. I am imaging M17 which is to the southeast. There should be no meridian flip any time soon.

Please fix this asap or I’ll need to rollback to previous version. 3.1 HF1 is unusable in remote observatory setup.

[Stefan B]

Please share the sequence you are using. Also which version did you upgrade from?

[Oleg Ignat]

I upgraded from 3.0. Here’s the target…

[Oleg Ignat]

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[Oleg Ignat]

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[Stefan B]

There has been zero change to the meridian flip trigger between 3.0 and 3.1.

The problem in your sequence is that you start tracking after finding home - thus leaving home position and the flip trigger will start to evaluate as the tracking out of the home position leads to being too close to meridian. Starting tracking is unnecessary. Any slew to a target will do that automatically.

[Oleg Ignat]

I can remove start tracking instruction if this resolves the problem. Thanks for looking so quickly into it. The thing is, I’ve been running this sequence for hundreds of hours for over a year. Only after upgrade to 3.1 I am starting to see this behavior. Even if meridian flip code did not change, there must be a change elsewhere causing this behavior.

[Oleg Ignat]

Also, if you look at the screenshot above, the meridian flip triggers not when I enable tracking, but rather on Slew instruction. It seems that the first thing Slew does is trigger meridian flip. If Slew actually slewed the telescope to the target before evaluating meridian flip conditions, the problem wouldn’t happen.

[Stefan B]

It triggers right before the slew instruction. Maybe there is a slight change of the timing over the year for it to happen now. I can assure you that nothing in this logic has been adjusted between these versions. The meridian flip trigger will not evaluate when the mount is not yet tracking, so this problem should not happen anymore then.

[Marc Blank]

Oleg - You might look into the Sequencer Powerups plugin and its safety features (When Becomes Unsafe/Once Safe). It’s much cleaner than what you’re doing to handle safe/unsafe.