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SkyPortal and SkySafari ignoring slew limits

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#1 jasonjeremiah

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Posted 20 April 2021 - 11:29 AM

Has anyone experienced an issue where both SkyPortal and SkySafari are ignoring the slew limits setting.  I set both slew limits to 70 and 20 to avoid ramming the diagonal or dew shield in the base while aligning using Starsense.  I had 3 encounters where the diagonal ran into the base.  I was using a wedge and my latitude is approximately 32 deg.  I am doing something wrong?  Am I calculating the slew limits wrongly.  I'm calculating based on angle perpendicular to base.  Thanks!



#2 mmcintosh1

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Posted 20 April 2021 - 11:49 AM

I have had a similar situation with my evolution, but only during the initial alignment for the night. I remove my diagonal so there is no collision.



#3 jasonjeremiah

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Posted 20 April 2021 - 03:00 PM

I have had a similar situation with my evolution, but only during the initial alignment for the night. I remove my diagonal so there is no collision.

I seemed to remember reading something from Mike Swanson saying that slew limits only applied when slewing and aligning and not when tracking.  So, if it fails when slewing and aligning, with no message of warning, what exactly is slew limits for?



#4 blaster

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Posted 20 April 2021 - 05:03 PM

Slew Limits – Sets the limits in altitude that the telescope can slew without displaying a warning message. The slew limits prevent the telescope tube from slewing to an object below the horizon.
The scope will operate within the limits set by you when operating under it's own software and slewing but if requested by the user under what is manual command it may display a warning but then will do as commanded by the user.
As you are manually slewing the scope you are in charge, foolishly or otherwise the scope will assume that you know what you are doing.
Slew limits are relative to the base of the mount not the horizon.

Sent from my SM-G935T using Tapatalk

#5 Michael_Swanson

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Posted 20 April 2021 - 08:27 PM

Hi Jason,

 

Sounds like you haven't set the wedge option in SkyPortal/SkySafari:

 

 

One-Time Setup
• Power up the mount. On your tablet or smartphone, open the WiFi connection
settings and connect to the Celestron-xx or SkyQLink-xx WiFi network being
broadcast by the telescope. If you have problems connecting or staying connected,
refer to Chap. 7 for troubleshooting steps.
• Start SkyPortal on your tablet or smartphone and tap the Connect button to begin.
If the Connect button is not displayed, tap the ‘scope button on the bottom of the
screen.
• Once connected, tap the orange Celestron logo to access the Setup and Control
screen. Ensure StarSense Wedge Align Enabled is selected. Select either Align
Using StarSense Auto or Align Using StarSense Manual and tap either the X
button in the upper right or the back button on your device. This setting is stored
for future use and does not need to be confirmed each time.
Important: if you later remove the wedge, remember to return to this menu to
deselect the wedge setting.
• Tap the Disconnect button.

 

After that, the alignment routine should know understand the scope's orientation during the alignment routine.  Be sure to follow the directions on the screen, most notably, moving the scope to the correct starting position (pointed towards the meridian and at the index mark on the fork arm).

 

Best regards,
Mike Swanson
https://www.NexStarSite.com



#6 jasonjeremiah

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Posted 22 April 2021 - 07:28 PM

Hi Jason,

 

Sounds like you haven't set the wedge option in SkyPortal/SkySafari:

 

 

One-Time Setup
• Power up the mount. On your tablet or smartphone, open the WiFi connection
settings and connect to the Celestron-xx or SkyQLink-xx WiFi network being
broadcast by the telescope. If you have problems connecting or staying connected,
refer to Chap. 7 for troubleshooting steps.
• Start SkyPortal on your tablet or smartphone and tap the Connect button to begin.
If the Connect button is not displayed, tap the ‘scope button on the bottom of the
screen.
• Once connected, tap the orange Celestron logo to access the Setup and Control
screen. Ensure StarSense Wedge Align Enabled is selected. Select either Align
Using StarSense Auto or Align Using StarSense Manual and tap either the X
button in the upper right or the back button on your device. This setting is stored
for future use and does not need to be confirmed each time.
Important: if you later remove the wedge, remember to return to this menu to
deselect the wedge setting.
• Tap the Disconnect button.

 

After that, the alignment routine should know understand the scope's orientation during the alignment routine.  Be sure to follow the directions on the screen, most notably, moving the scope to the correct starting position (pointed towards the meridian and at the index mark on the fork arm).

 

Best regards,
Mike Swanson
https://www.NexStarSite.com

I wish it were that simple.  I should have stated in my original post that I had wedge align enabled in the settings.  I also made sure that index marks were aligned before even starting the app.  I had a few minutes to do some testing last night with CPWI, and while it didn't ram the mount, StarSense only produced one image that CPWI could plate solve.  On the second attempt, I encountered more issues that resulted in it being the end of the night.  I had cord wrap enabled, but did not seem to make a difference as the mount kept doing full turns in azimuth and was getting close to yanking cord out of the adapter inlet.  I unwrapped the cord and continued letting StarSense do it's thing, and then heard the sound of hard plastic hitting the pavement.  The wifi dongle I was using got wedged between one of the knobs sticking up from the wedge and it tore the cable completely out of the RJ12 connector, leaving the connector in the AUX port and dongle in pieces on the ground.  Mount kept moving in azimuth even after the wifi dongle was disconnected so I pulled the plug and called it a night.


Edited by jasonjeremiah, 22 April 2021 - 07:35 PM.


#7 robbieg147

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Posted 09 May 2021 - 01:35 PM

I have always understood that slew limits are only honoured once a alignment of some sort has been completed, as until then the scope does not know where it is?



#8 jasonjeremiah

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Posted 09 May 2021 - 01:43 PM

I have always understood that slew limits are only honoured once a alignment of some sort has been completed, as until then the scope does not know where it is?

This was during a StarSense alignment.




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