Hey Team,

My ap1100 Non AE mount seems to have lost direction now. Goto and park slew to random dangerous directions.

I have tried moving the mount using apcc to random position in the sky , plate solve and recal that did not seem to help.

Mount  is in remote obsy, so I cannot reset using clutches. 

I had not configured the home position in the apcc yet, as I am still learning to use apcc . Could some one advise how to reset the home position?  

Thanks! 

TK

Hi Tarun,

1. Power down the mount.

2. Release clutches.

3. Put the mount mechanically in Park 3 (or any other well-known park position)

4. Tighten up the clutches and power up the mount

5. Using the keypad or APCC or Sky Safari, "Unpark" the mount from the well-known park position. Don't use "last parked" in this case.

6. Now GoTo to a star, platesolve/sync it.

The key is to align the non-Mach2 mounts mechanically -- which is done by Unparking from well known position. Sync is needed in addition to this unpark command.

Unless you're setting this up on a pier, I don't believe Home is as useful (but happy to stand corrected).

On Tue, Nov 29, 2022 at 12:25 AM Tarun Kottary <tkottary@...> wrote:

Hey Team,

My ap1100 Non AE mount seems to have lost direction now. Goto and park slew to random dangerous directions.

I have tried moving the mount using apcc to random position in the sky , plate solve and recal that did not seem to help.

Mount  is in remote obsy, so I cannot reset using clutches. 

I had not configured the home position in the apcc yet, as I am still learning to use apcc . Could some one advise how to reset the home position?  

Thanks! 

TK

So when you (for example) tell it to park at park 5, it will move to some wild orientation and “park” there? Does it end up in the same position for one night and a different one the next, or is it a different wild position each time you tell it to park at the same place, no matter the interval between attempts?

If it is consistently wrong for a night at one position and is parking at a somewhat different position the next, I would suspect the time on your PC is at issue and the CP keeps getting programmed with it. 

If time on your PC is ok and thus time on the CP would be, then perhaps your CP has lost its mount characteristics and needs to be reset to know it’s hanging off an 1100. 

Last idea, since this is a remote installation, is the CP always powered on? If so, have you tried to get someone to do a good old power cycle on it?

On Nov 29, 2022, at 03:25, Tarun Kottary <tkottary@...> wrote:

Hey Team,

My ap1100 Non AE mount seems to have lost direction now. Goto and park slew to random dangerous directions.

I have tried moving the mount using apcc to random position in the sky , plate solve and recal that did not seem to help.

Mount  is in remote obsy, so I cannot reset using clutches. 

I had not configured the home position in the apcc yet, as I am still learning to use apcc . Could some one advise how to reset the home position?  

Thanks! 

TK

Tarun,

A quick and dirty way to get to Park 3 requires two steps:
1) Use the E-W-N-S buttons to get as close to Park 3 as the safety limits will allow (as you've already done), then unpark from Park 3.
2) Now you should be able to get to Park 3 with the N-S-E-W buttons, do so.  Then do another unpark from Park 3.

To establish a "home" position, use the "Homing/Limits" tab in APCC while the mount is "connected".  There is a button for "configuring" home and limits.  Any time you move a clutch, you MUST reconfigure home and limits.

Regards,
Mike

Oops, my bad!  I missed the remote part.  Mike's suggestion will work just fine then.  The intermediate park is needed to reset the internal limits to allow the mount to get into the position you desire - Park 3 - using the direction buttons.    

Followup Q on Home usage. 

The manual makes it very clear that if one were to loosen the clutches, then we need to re-configure the Home position. Do you know if this (the bolded part) is strictly required if the goal is to help recover a lost mount? Of course, this wouldn't work if I loosened the clutches and rotated the Dec plate 90 degrees (or RA, for that matter).

For a more common case of, say, less than a few degrees or so of movement on either axis with the clutches loose, can the once-configured Home position be re-used to establish a rough park position? One can perform a Sync (not ReCal) afterward to align with the celestial coordinates.

Note Tarun's mount is non-AE, so in case there's a difference, I am curious to know if AE mounts behave differently in this regard. I was about to post a question regarding this for my AE mount separately but given we have this thread on this topic already, I'll post here in this thread if that's ok.

Thanks.

On Tue, Nov 29, 2022 at 9:17 AM Howard Hedlund <howard@...> wrote:

Oops, my bad!  I missed the remote part.  Mike's suggestion will work just fine then.  The intermediate park is needed to reset the internal limits to allow the mount to get into the position you desire - Park 3 - using the direction buttons.    

The clutches on our 1100/1600 mounts act as variable positioning devices for the scope. It's the same kind of action as taking your scope and mounting it sideways or flipping it 180 degrees in the rings so it points at the ground. The mount itself still points to the north pole (in the case of Park3), but the scope is now pointing completely opposite or at right angles to where the mount is pointing. So, in these cases is the mount lost or is the scope lost?

In the case where the clutches are never loosened or the scope is not re-oriented, such as in a remote setup, you can get the mount and scope lost by doing an errant recal or sync on the wrong target. For instance, if your scope is pointed to a star in the east and you then do a sync or recal on a star in the opposite direction in the West, the mount will happily shift both RA and DEC coordinates by 90 degrees and assume that what you did was correct. At that point all subsequent slews will be in error and both the scope and the mount are "lost".

In both instances above, whether the 1100/1600 mount has encoders or not makes no difference. For a permanent 1100/1600 setup, if the mount is set with clutches tight and never loosened, APCC has a Homing button that sends the mount to a pre-determined home position (Park 3 being the most ideal). Sending the mount "Home" in APCC allows the mount to re-orient itself to a known position from which you can then re-start the mount. Simply set startup to "Resume From Park3" (assuming Park 3 is your Home position). If for some reason you have chosen a random position for your "Home" in APCC, then re-orienting the mount is not that simple.

The exception is the Mach2 mount which has built-in shaft encoders that pick up rotation of the axes when the clutches are loosened. In that mount you can also always send the mount Home which then automatically recalibrates the position of the scope after an errant sync or recal. No power cycle or re-start is needed to re-orient the mount after an errant sync or recal.

Rolando

-----Original Message-----
From: Arvind <base16@...>
To: main@ap-gto.groups.io
Sent: Tue, Nov 29, 2022 11:46 am
Subject: Re: [ap-gto] Ap1100 lost directions

Followup Q on Home usage. 

The manual makes it very clear that if one were to loosen the clutches, then we need to re-configure the Home position. Do you know if this (the bolded part) is strictly required if the goal is to help recover a lost mount? Of course, this wouldn't work if I loosened the clutches and rotated the Dec plate 90 degrees (or RA, for that matter).

For a more common case of, say, less than a few degrees or so of movement on either axis with the clutches loose, can the once-configured Home position be re-used to establish a rough park position? One can perform a Sync (not ReCal) afterward to align with the celestial coordinates.

Note Tarun's mount is non-AE, so in case there's a difference, I am curious to know if AE mounts behave differently in this regard. I was about to post a question regarding this for my AE mount separately but given we have this thread on this topic already, I'll post here in this thread if that's ok.

Thanks.

On Tue, Nov 29, 2022 at 9:17 AM Howard Hedlund <howard@...> wrote:

Oops, my bad!  I missed the remote part.  Mike's suggestion will work just fine then.  The intermediate park is needed to reset the internal limits to allow the mount to get into the position you desire - Park 3 - using the direction buttons.    

--
Roland Christen
Astro-Physics

So in effect, considering a remote non AE setup, while the 1100 can get lost it can always be recovered by the method above? Is that correct? 

Bob,

My scope is not exactly  at Park 3 now , but close. I am still somewhat off in Dec. Goto  is off by dec offset.  

On Wed, Nov 30, 2022 at 6:38 PM Bob <astro@...> wrote:

So in effect, considering a remote non AE setup, while the 1100 can get lost it can always be recovered by the method above? Is that correct? 

Tarun, Park 3 is just an approximation and not a hard stop given the way we operate the mount. (Unlike Mach2). 

So as long as you sync on a star (not recal, I think) I’d imagine CP4 would then correct for any residual Dec offsets. 

On Fri, Dec 2, 2022 at 21:04 Tarun Kottary <tkottary@...> wrote:

Bob,

My scope is not exactly  at Park 3 now , but close. I am still somewhat off in Dec. Goto  is off by dec offset.  

On Wed, Nov 30, 2022 at 6:38 PM Bob <astro@...> wrote:

So in effect, considering a remote non AE setup, while the 1100 can get lost it can always be recovered by the method above? Is that correct?