Can someone explain how to use a rotator?

I have a Moonlite NiteCrawler rotator and wish to use this with Voyager. However, I guess this is a language issue but I cannot understand what to do with it.
I open the web dash board, and go to the virtual field of view and select solve position and PA (Voyager takes a photo). What do I need to do after this? Do I have to copy something somewhere? I know there is a version 2 ascom or version 3, and I am using version 2. Thing is, I get no feedback that I am aware of if I change the position of the rotator and then load a roboclip and use it in a sequence. I do not see anything in the log about the rotation.
I would appreciate a detailed step by step explanation. I struggled with this in the SkyX as well but finally got that going right. No software I know of has yet to explain this correctly in a step by step fasion…
So if anyone has got this working properly, please tell me how.
Thanks, Tom

We have two Nitecrawlers for dual scope setup and both works fine (extreme accuracy; impressive). I think all you need is a one-time intial sync, and after that you are basically all set even if you don’t sync again.

Easiest way for me is just manual sync the solved PA; you can do that via the gadget list on the right, under “rotator” you can enter the solved PA and click “manual sync”.

Or, in DragScript you can do something like “precise rotate skyPA” in rotator category, which will rotate the rotator to your specific sky angle. You can add a “sync rotator” after that, so that now the angle is matched to skyPA and will be remembered.


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Great. I guess I just didn’t quite understand that you need to do a manual sync the first time, or how to do it.
This should solve the issue.
Many thanks, Tom

No sync is needed and no sync to sky pa. Just select your rotator angle and choose if you want sky pa or rotator pa. Nothing else.
Voyager will do the job for you. Please not make difficult things that are really easy to do.

You found explanation on the Voyager wiki

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Ok sorry to make it complicated then. My bad. Reason I need to sync my rotator angle to sky angle is I need to run with Array, which I can’t do a “precise rotate to skyPA” as far as I know.

My method did work for me anyway :slight_smile:

no problem @yzhzhang I just dont want users not know the right way. In your case if you sync to PA when you will have meridian flip the sky PA is not equal to the rotation you sync and work before meridian. You will have image rotated of 180° and if you have a choosed guide star you will not have where you think to have.

I like yzhzhangs explanation. The wiki says,

You will input manually the angle to sync.

If you have driver type (A) Voyager will calculate automatically for you the Offset and value will be stored in actual Voyager Profile.

This explanation is not complete. When someone has not used this before, the wiki does not explain this well enough to actually use a rotator.

A better explanation is,

  1. Take a picture.
  2. Get precise position and PA using the web dash board.
  3. Go back to voyager and press the sync button in the rotator widget.

The offset will then be saved in the profile. You will not need to change this in the future.

Step 1 and 2 are not there and for someone who has not done this before, it is not clear.
I hope this clears my confusion.
Best regards, Tom

Hey Tom,

I think Leonardo’s point is, you don’t necessarily need to make your rotator angle match with sky angle (although I did that and find it easy).

Instead of do a sync to sync your rotator angle with sky angle, you can just use the “precise rotation” function (or whatever built-in steps in sequence, etc.); I guess it will rotates your rotator with plate solving, and correct the angle iterratively. You will still have a displayed difference with rotator angle and actual sky angle, but it doesn’t matter; presice pointing makes sure your end result is OK.

I should probably stop guessing. This is just my understanding of what you guys are discussing…


No sorry this is no explanation, offset is not sync to sky PA and offset is only reserved to voyager windows not in dashboard. In Dashboard you can change your rotator PA. Sky pa is managed in sequence or in onthefly automatically. I do an hard job to remove things to do to the final user to not have problem.

Ok, next clear night I will try two sequences with different PA. I will do nothing but run each sequence.
This would be great.
Thank you.

wonderful use planetarium or virtual fov in dashboard to create object in roboclip and import in sequence or use target and PA manually and, always in sequence, choose to manage rotator and to use skypa mode for rotator angle. Decide if after meridian you want to mantain the same image orientation. Thats all.

All the best

Ok. So I had my chance to use two sequences, each which had different PA (90 degrees different). The first sequence was already on the target with the PA from the previous night.
I then finished, and loaded the other sequence. I ran it. It did NOT rotate the rotator. Yes, it is selected to be managed in the sequence.
I tried many things. The only thing that worked is to click the “Manual Sync” button in the Rotator Command widget. This is exactly what is said in the Wiki and by yzhzhang above. From that point it worked. It now works.

However, the webdashboard, FOV does not show the correct PA unless I solve position and PA. It should display this without solving by just clicking Get telescope position.
So a manual sync is necessary (As stated in the Wiki!) at least once.
Best regards, Tom

I just want to clarify something.
Once everything is working and you slew to a new target in a sequence and you rotate the imager, if you then click on “get telescope position” in the virtual field of view it shows the new location, but it does not show the VFOV with the correct PA.
This information IS available in Voyager. It shows it on the screen in the rotator box.
This should be fixed.
Same thing for the Camera information in the web dash board. It does not show the exposure or filter. The information is available in Voyager when the sequence is running.
Best regards, Tom

Hi Tom,


  • sync is not related to SkyPA , also because SkyPa change with meridian side if you use the same mechanical position of rotator
  • sync in Voyager is to set the equatorial position or do a zero for you personal and custom reasons
  • you dont need to sync anything in Voyager, just (in sequence configuration) set the rotation angle as set if is a SkyPA or RotatorPA. In first case Voyager will adjust Rotation for you to match SkyPA requested using closed loop and plate solving. In second case if you use rotator PA Voyager just position the rotator at position request. If you choose to mantain orientation Voyager will take care of calculating the right position to use.
  • If you want to test without sequence or just want to position the rotator use the “Precise Pointing target coord and PA” in onthefly. There is also a dedicated block in DragScript with only Rotation management for Precise Sky PA set (on the actual position of Mount)
  • Webdashboard has 2 indicators for rotator 1 is mechanical position and one is LAST PA solved. First is auto updated, second only when a solving is done and Sky PA solved
  • Webdashboard show without problem the current shot running

You are free to use Sync how you want for sure.

If you think to have issue and Voyager have a bug YOU MUST use the support channels, with evidence of problem, configuration, session and log.

Topic closed.

All the best

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