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Stupid Question about pier side

thomas.westerhoff24@...
 

Well, that might be a stupid question, but since english is not my mother tongue, I better ask.
I can enter the pier side in Onstep. But what does that mean? Does "West" mean that the telescope is on the west side of the pier or pier west of the telescope?
--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/

Howard Dutton
 

Pier side West means the telescope is West of the pier looking at the sky East of the meridian.

Howard Dutton
 

On Fri, Jan 3, 2020 at 04:50 AM, Howard Dutton wrote:
Pier side West means the telescope is West of the pier looking at the sky East of the meridian.
Well, it's really more complicated than that...
https://ascom-standards.org/Help/Platform/html/P_ASCOM_DeviceInterface_ITelescopeV3_SideOfPier.htm

Charles
 

Hi all,
 
In the FS2 system there was no side of pier but a pointing direction wich is defined in the opposite manner. That's why Thomas and many FS2 users are when they switch to onstep or teenastro confused.
 
Charles
Gesendet: Freitag, 03. Januar 2020 um 13:52 Uhr
Von: "Howard Dutton" <hjd1964@...>
An: main@onstep.groups.io
Betreff: Re: [onstep] Stupid Question about pier side
On Fri, Jan 3, 2020 at 04:50 AM, Howard Dutton wrote:
Pier side West means the telescope is West of the pier looking at the sky East of the meridian.
Well, it's really more complicated than that...
https://ascom-standards.org/Help/Platform/html/P_ASCOM_DeviceInterface_ITelescopeV3_SideOfPier.htm

thomas.westerhoff24@...
 
Edited

Hello Charles,

yes this is really confusing if you are used to FS2 I have a fixed setup and therefore don't need any complicated align. Also I don't need a time. The mount is always aligned exactly to the north pole. In the pictures you can see the mount with the telescopes on both sides. Their parking position is horizontally aligned to the south, so I can close the sunroof.   I switch on FS2, release the clamp and move the telescope of my choice to a star. Then I center the star in the eyepiece and sync on it. The FS2 then asks just on which side of the mount the telescope just used is. If I work for example with the 30cm Cassegrain on the left side, I choose Eest. If I use the Kutter Two-Mirror Tilted Telescope on the left side I choose East. That's it. Very simple.


--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/

Howard Dutton
 

Set the date time automatically via RTC or ASCOM/computer.

No need to align... push the 'scope to target and sync.  Tracking will then start.  But... having the sync pushed through to the encoder subsystem is still on my to do list.

thomas.westerhoff24@...
 
Edited

Is there a way to disable the automatic meridian flip an set the pier side manually. Because of the limited movement of the tangential drive in DEC I have to do the flip manually. 

And I have found that the pier side in Onstep is always the same whether I use the right or left telescope. It looks like it depends only from the position of the star in the Sky.

The DEC encoders on the left side run in reverse direction of the DEC encoder on the right side. I think that FS2 does exactly this with the query if you have the telescope on east or west. So the DEC encoder direction is simply reversed. 
--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/
https://www.facebook.com/VolkssternwarteKirchheim/

Khalid Baheyeldin
 

On Mon, Jan 13, 2020 at 11:31 AM, <thomas.westerhoff24@...> wrote:
Is there a way to disable the automatic meridian flip an set the pier side manually. Because of the limited movement of the tangential drive in DEC I have to do the flip manually. 
Do you have the Android App?
If so, go to Initialize, then at the bottom under Automatic Meridian Flip, select Off.
Only when you have it on, does the automatic flip occur.

Similar settings can be found in other OnStep clients.

thomas.westerhoff24@...
 

Ah thanks. I will download the app. ;-)
--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/
https://www.facebook.com/VolkssternwarteKirchheim/

Howard Dutton
 

On Mon, Jan 13, 2020 at 08:31 AM, <thomas.westerhoff24@...> wrote:

Is there a way to disable the automatic meridian flip an set the pier side manually. Because of the limited movement of the tangential drive in DEC I have to do the flip manually. 

And I have found that the pier side in Onstep is always the same whether I use the right or left telescope. It looks like it depends only from the position of the star in the Sky.

The DEC encoders on the left side run in reverse direction of the DEC encoder on the right side. I think that FS2 does exactly this with the query if you have the telescope on east or west. So the DEC encoder direction is simply reversed. 

I think the preferred pier side (Best/default, East, West) feature might help you but not sure, depends on exactly how you use the 'scopes what their range of travel is etc.  SHC, web, etc. have control of this.

Not sure I see what's wrong.  Swing telescope #1 into the "normal orientation" (where the OTA back isn't positioned under the mount) and the Sync will choose the best pier side.  Same will happen for telescope #2.

I guess what you're saying is there are cases where you want to stay "under the pier" and not have sync force you to do the flip.

Howard Dutton
 

Just be sure to adjust the limits (meridian and overhead specifically) to allow the required range of "motion" so Sync is allowed where you need it to be allowed.

Howard Dutton
 

Do let me know if the encoder Sync support I just coded seems to be working when you get a chance.

thomas.westerhoff24@...
 

Good morning, Howard,

yesterday evening I finally got around to testing the changes. It works perfectly. Due to the extended limit range a much longer observation time without Meridan flip is now possible at our telescope.  Switching to the telescope on the other side is possible. You have to click through some submenus, because the pier side change is a bit hidden in the configuration menu, but it was important to me that it works without problems.

I have rarely seen an Open Source project with such good and fast support. Thumbs up!!!

--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/
https://www.facebook.com/VolkssternwarteKirchheim/

Howard Dutton
 

Thank you, glad things are working to your satisfaction.

I still intend to look at the SHC design and perhaps add a Config.h option to have it ask for pier side during a Sync.

Another feature I always thought to add for tangent arm mounts w/encoders is a limp-to goto mode where OnStep remembers the Dec axis range of travel and home position.  When it detects the mount being manually moved (> whatever threshold deg/s when not doing a slew/goto) it'll center the Dec tangent arm.  You can then do short gotos in the area as soon you have the mount roughly positioned.  Since OnStep knows the Dec range of travel If you choose a target outside of the range the goto will fail.  An additional layer of coordinate conversion could be added to handle the tangent arm geometry too.  For these tangent arm mounts it's a heck of a lot cheaper/easier to design something like this vs. converting that Dec axis to full range.  Usefulness would depend on just how much range of travel that Dec axis has.