If this is already possible, please advise how. Otherwise, I would like to have the possibility to suspend dome movement during a meridian flip. I see no point in the dome doing a 360 deg. turn trying to track the telescope. Today I do manual MF and suspend tracking of the dome up front, but I would like to move to automatic MF. If this mean that dome needs to be disconnected and reconnected I would be fine with that.
I agree with @Heno.
I also “de-sync” my dome before a Meridian Flip to prevent the dome chasing the flipping scope all round the sky. It would be great of there was a setting to suspend dome updates until after the scope has flipped. Dome updates would clearly need to be resumed before any post-flip platesolving and recentring was carried out.
Cheers
Steve
I control a setup with SGP with a dome and don’t see this behaviour.
Do you connect the dome directly to SGP or through POTH?
The ASCOM hubs intercept the slew commands and use the destination rather than the current position to determine the target dome position. That should avoid problems with the dome chasing the mount all round the sky.
Another thing is that the slew should not be considered complete until both the mount and dome have stopped in their new positions.
The same applies to any slew of course, not just meridian flips.
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@Steve1962, thanks for the support.
I have a home built observatory/dome and I’m using the Lesve dome driver. It checks the dome/scope position and moves the dome if it is more than 2 deg. misaligned. I have not tried, but I just don’t see how this driver could know that there is a meridian flip in progress. I assume the dome will move immediately as it does with any slew command.
I have tried the POTH, but I had a lot of sync drop-outs and I was not happy with it. So now I connect SGP directly to the dome through the Lesve driver.
Ideally the dome movement should be suspended until the scope has reached its final position. If so, the dome would only move a few degrees to adjust the opening. That’s what I’m looking for.
Heno….you should try it and then report what you see. If there is a problem - then the logs will be useful.
Kinch.
Agree entirely. Speculating about how this works without trying it isn’t going to be productive.
As I said previously a well designed application, or hub, will monitor both the scope position and slews and use whichever is appropriate to control the dome. SGP could easily already be doing this.
POTH could also do it BUT requires that the scope is controlled through POTH, not using it on the side where it can’t see the mount slew commands.
I suggest that you try using SGP to control the mount and dome. see how slews, commanded through SGP, manage the dome position. You must do the slews using SGP to see how it manages this.
I’ve done some tests using a Celestron AVX and a simulated dome The slaving is set uo in SGP.
Everything is fine. When a slew is commanded from SGP the dome moves directly to the target. If the slew is doing a meridian flip then the dome only moves the short distance to the final position. it does not go all round the houses.
Slews not controlled by SGP also seem OK, I get the impression that SGP sees that a slew is in progress and waits for it to finish before moving the dome.
So now I’ve checked it in real life and no, there is no problem. Sorry for the fuzz.
The scope actually started moving immediately as the flip set in, but in opposite direction of what I expected and what the telescope did. So it only moved to adjust the opening correctly and that was it.
One thing to notice though. First time I tried I had set up a target just before the meridian, but not actually started the sequence. Scope was tracking so I was expecting the MF to occur. But it did not. So if I had left it there it would eventually have banged into the pier.
I assume this is by design? And maybe not a relevant problem in real life?
We will only issue a meridian flip as part of a sequence. If a sequence is not running we’re not really controlling your telescope.
As for the meridian flip and the dome positioning, when we issue the slew for the mount we calculate the position for the dome and also issue a slew for the dome where the mount will end up. Thus there should be no “hunting” between the dome and the mount during the flip.
Thanks,
Jared