HEQ5 PRO Mount - Home position vs. an actual Park position

[rockinrome]

Hello all

I know there have been some threads on this, but not one *I think* has answered this question....

Let's assume that we have a perfectly polar aligned system and we all know that Home position is when scope is pointing at the NCP and that's all good. (There are loads of articles about how to achieve this - all good, sorted.)

BUT..... Is there a way to have an automated park position at the end of a session - like counter-weights left, scope to the right. Then when we come to another session, do an "un-park" and it moves to the home position, ready for use?
So when we switch on in this case the mount knows it's parked and not at home position as this would be incorrect to start from.

I know that you can specify "Home at current position". Is this the answer?, i.e. move scope with handset to best position for me and then use that as the "park". 

What I am trying to achieve here is a non-manual (which is error prone) solution.

Thanks for reading.
Matthew
 

 

[StevieDvd]

You are mixing up Polar Alignment and mount position.  Home position is a useful starting point for most mounts, some do have an automated park/start position - the HEQ5 does not.

NCP alignment is the mount not the scope and is needed for accuracy of goto's on eq driven mounts.

Using your example of a perfect NCP alignment, what is needed on startup is to tell the mount where the scope is currently pointing. If it thinks it is at the standard home position but it's not, then the gotos will be wrong, though a bad date/time/location can have the same effect.

A lot of astro software will let you save a start position, that is effectively your home position now. You would not need to go to the old weights down/scope north home position.

When I had an HEQ5 mount and was polar aligned I would start at my home position, marked on my mount. Then do a goto to a bright star and if not centred I;d release my clutches and centre it, then do a goto home to check it was at my home marked on the mount. All gotos were then OK for me.  The current equivalent can be done my plate-solving and re-centering.

Star alignments are for letting the mount know of any inaccuracies in your Polar alignment and in where the mount is pointing (if not correct) it can then run taking these into account.

HTH

Steve

[Albir phil]

Hi as far as I know if you set mount to current position you can begin next session from there, however I always return to home position,never tried current position. When you use home position it tells you it is saving data,not sure if current dose🤔

[rockinrome]

5 minutes ago, StevieDvd said:

You are mixing up Polar Alignment and mount position.  Home position is a useful starting point for most mounts, some do have an automated park/start position - the HEQ5 does not.

NCP alignment is the mount not the scope and is needed for accuracy of goto's on eq driven mounts.

Using your example of a perfect NCP alignment, what is needed on startup is to tell the mount where the scope is currently pointing. If it thinks it is at the standard home position but it's not, then the gotos will be wrong, though a bad date/time/location can have the same effect.

A lot of astro software will let you save a start position, that is effectively your home position now. You would not need to go to the old weights down/scope north home position.

When I had an HEQ5 mount and was polar aligned I would start at my home position, marked on my mount. Then do a goto to a bright star and if not centred I;d release my clutches and centre it, then do a goto home to check it was at my home marked on the mount. All gotos were then OK for me.  The current equivalent can be done my plate-solving and re-centering.

Star alignments are for letting the mount know of any inaccuracies in your Polar alignment and in where the mount is pointing (if not correct) it can then run taking these into account.

HTH

Steve

Thanks for the quick reply Steve.

With respect though - I am not mixing anything up (may have not explained properly of course?), I was very careful to say Home and Park as I know these are interchangeable sometimes.

I guess the escence of what I am saying is that I would like to simply return to where I left off or at least back to Home when I switch on again without any start alignment etc. BUT I do need to move the scope to a suitable "parking" place before I close the obs.
You said "A lot of astro software will let you save a start position, that is effectively your home position now. You would not need to go to the old weights down/scope north home position." - I *think* this what I am after - a software solution (or handset at a push!)

Best regards
Matthew

 

[rockinrome]

5 minutes ago, Albir phil said:

Hi as far as I know if you set mount to current position you can begin next session from there, however I always return to home position,never tried current position. When you use home position it tells you it is saving data,not sure if current dose🤔

Thanks for the confirmation - that's what I've read and make sense.

Matthew

[vlaiv]

Park position should be position where the scope is "parked" between sessions.

It is mostly important for two reasons:

1. having dome or otherwise closing observatory so that telescope can't be left in normal home position (for newtonian telescopes it is better to leave scope with mirror on its side so that dust does not settle down on the mirror).

2. When using periodic error correction and not having encoders. Here - software that controls the telescope assumes that telescope is at its park position when powered on - meaning stepper motors are oriented the certain way and haven't been moved. If steppers have been moved (not to be confused with manually moving the scope when clutches are undone) without software not knowing about it - then synchronization information between software and hardware is lost and periodic error correction will be wrong.

Home position is just "start" position for goto moves. It is usually defined as scope pointing to Polaris and counterweights down (that is RA 6h and DEC 90 degrees).

Most people don't bother and do not use two different positions - they use the same position for both of these uses - it does not matter if it is usual home or sideways parked.

In any case - home should be thought as scope orientation between moves / gotos / trackings and park should be thought of as permanent home between power cycles and is more related to internal gearing and motor positions.

[rockinrome]

7 minutes ago, vlaiv said:

Park position should be position where the scope is "parked" between sessions.

It is mostly important for two reasons:

1. having dome or otherwise closing observatory so that telescope can't be left in normal home position (for newtonian telescopes it is better to leave scope with mirror on its side so that dust does not settle down on the mirror).

2. When using periodic error correction and not having encoders. Here - software that controls the telescope assumes that telescope is at its park position when powered on - meaning stepper motors are oriented the certain way and haven't been moved. If steppers have been moved (not to be confused with manually moving the scope when clutches are undone) without software not knowing about it - then synchronization information between software and hardware is lost and periodic error correction will be wrong.

Home position is just "start" position for goto moves. It is usually defined as scope pointing to Polaris and counterweights down (that is RA 6h and DEC 90 degrees).

Most people don't bother and do not use two different positions - they use the same position for both of these uses - it does not matter if it is usual home or sideways parked.

In any case - home should be thought as scope orientation between moves / gotos / trackings and park should be thought of as permanent home between power cycles and is more related to internal gearing and motor positions.

Thanks for the reply vlaiv.

So, yeh, I get what's said here - the power-cycling bit is key to me here.

Matthew

[rockinrome]

I may have the answer but looks like it will involve the hand controller. Not really a problem though at this stage.

The attachment is from the SynScan guide and says you can call any position (I assume moved by the hand controller or software controlling the mount) the home position and then recall that the next time you power on.

So - with gudie in mind I would do:

(1) First time move scope under control to my park position
(2) Function > Park to... Current Pos
(3) Then next session use Start from Park "Yes"
(4) Second and further times, Function > Park Position (park to last park position)

Thanks again all for your help/comments.

Matthew

[StevieDvd]

4 hours ago, rockinrome said:

Thanks for the quick reply Steve.

With respect though - I am not mixing anything up (may have not explained properly of course?), I was very careful to say Home and Park as I know these are interchangeable sometimes.

I guess the escence of what I am saying is that I would like to simply return to where I left off or at least back to Home when I switch on again without any start alignment etc. BUT I do need to move the scope to a suitable "parking" place before I close the obs.
You said "A lot of astro software will let you save a start position, that is effectively your home position now. You would not need to go to the old weights down/scope north home position." - I *think* this what I am after - a software solution (or handset at a push!)

Best regards
Matthew

 

By mix up it was the linking of NCP to home position by where the scope is pointing.  NCP can be set without a scope mounted.

But of course if you setup your mount & scope for each session, and/or need to polar align then you will likely move the mount from whatever saved position or home to do so.  If you are in an observatory and have PA sorted you can do a restart more easily, but in that case I doubt the original question would have asked. 

Can you let us know what software you are using and someone will point out where you can store your preferred start position?

If you are not leaving the mount in the close down position for next time even the saved position is effectively lost.  Plate-solving can be the answer you need as it can update the mount position for you as long as it can solve the image seen by the controlling software. 

[rockinrome]

2 hours ago, StevieDvd said:

By mix up it was the linking of NCP to home position by where the scope is pointing.  NCP can be set without a scope mounted.

But of course if you setup your mount & scope for each session, and/or need to polar align then you will likely move the mount from whatever saved position or home to do so.  If you are in an observatory and have PA sorted you can do a restart more easily, but in that case I doubt the original question would have asked. 

Can you let us know what software you are using and someone will point out where you can store your preferred start position?

If you are not leaving the mount in the close down position for next time even the saved position is effectively lost.  Plate-solving can be the answer you need as it can update the mount position for you as long as it can solve the image seen by the controlling software. 

Thank you.

I currently use NINA.

Thanks again
Matthew

[Budgie1]

If you're using NINA, then are you also using EQMOD?

If so, then expand the EQMOD GUI (Fig 1 in the image below) and in the central column, at the bottom, are the Park controls. In the drop-down you get the choice of Park to Home Position or Park to a custom position (I can't remember the exact wording on the drop down menu ).

You'll find details on page 88 of the EQMOD Manual.

I have this set for my HEQ5 in my ROR Obsy, so the scope is laying horizontal when parked, to allow the roof to roll over it.

[rockinrome]

7 hours ago, Budgie1 said:

If you're using NINA, then are you also using EQMOD?

If so, then expand the EQMOD GUI (Fig 1 in the image below) and in the central column, at the bottom, are the Park controls. In the drop-down you get the choice of Park to Home Position or Park to a custom position (I can't remember the exact wording on the drop down menu ).

You'll find details on page 88 of the EQMOD Manual.

I have this set for my HEQ5 in my ROR Obsy, so the scope is laying horizontal when parked, to allow the roof to roll over it.

Thanks Budgie1 - just the kind of "automation" I was after.

Kind regards
Matthew
 

 

 

 

[rockinrome]

Thanks again all that have replied here.

This forum is ace and you guys always come up with the goods and give plenty of food for thought.

All the best
Matthew

 

[Varavall]

12 hours ago, rockinrome said:

I currently use NINA.

Hi

I have the same mount and use NINA and park to a custom position so I can close the cover. What I have found is that once the custom park is set in NINA at the end of the imaging session the telescope duly parks where I want it. However, on start up when the telescope is unparked NINA assumes the telescope is at the home position so all goto slews go wrong. So what I do when I start up is to unpark and then park to home position, telescope goes pointing north and then everything works as it should. Guess that's a "bug" in NINA, but nothing major once known abut the foible. Hope that's useful.

Edited November 9, 2023 by Varavall
Error corrected

[rockinrome]

9 minutes ago, Varavall said:

Hi

I have the same mount and use NINA and park to a custom position so I can close the cover. What I have found is that once the custom park is set in NINA at the end of the imaging session the telescope duly parks where I want it. However, on start up when the telescope is unparked NINA assumes the telescope is at the home position so all goto slews go wrong. So what I do when I start up is to unpark and then park to home position, telescope goes pointing north and then everything works as it should. Guess that's a "bug" in NINA, but nothing major once known abut the foible. Hope that's useful.

Thanks for the insight Varavall. These are the little things that trip us all up!

Matthew

[StevieDvd]

2 hours ago, Varavall said:

Hi

I have the same mount and use NINA and park to a custom position so I can close the cover. What I have found is that once the custom park is set in NINA at the end of the imaging session the telescope duly parks where I want it. However, on start up when the telescope is unparked NINA assumes the telescope is at the home position so all goto slews go wrong. So what I do when I start up is to unpark and then park to home position, telescope goes pointing north and then everything works as it should. Guess that's a "bug" in NINA, but nothing major once known abut the foible. Hope that's useful.

That does not make sense to me. The unpark should update the mount coordinates to match the saved park position. If you tell yours to go to the home position and it does then it must know the saved position. It could be a case of the shutdown procedure i.e. if the mount is switched off first/last or when the eqmod is closed,  but that's best answered by an eqmod user who parks in a saved position.

[adyj1]

5 hours ago, Varavall said:

However, on start up when the telescope is unparked NINA assumes the telescope is at the home position so all goto slews go wrong. So what I do when I start up is to unpark and then park to home position, telescope goes pointing north and then everything works as it should. Guess that's a "bug" in NINA

This is also my experience. It isn't NINA causing this, but EQMOD and your mount. If you power off everything between sessions, then when you start EQMOD it will revert to its default start position - and assumes the scope is weights-down, pointing North. As far as I know there isn't a setting to get EQMOD to change this power-on default (although I have no experience of encoder-equipped mounts).

I am lucky enough to have an observatory, and as long as I maintain power EQMOD 'remembers' the custom park position. However, just to be on the safe side when I start a new session after any kit has been powered off, I run my planetarium software (CdC) and sync position with the mount before carrying out any slews. I can then see on the screen where my mount 'thinks' it is pointing, and if it is North rather than 'sideways-parked' I open the roof and manually point the scope north before then carrying on with my session...

HTH Ady    

Edited November 9, 2023 by adyj1
typo

[rockinrome]

6 minutes ago, adyj1 said:

This is also my experience. It isn't NINA causing this, but EQMOD and your mount. If you power off everything between sessions, then when you start EQMOD it will revert to its default start position - and assumes the scope is weights-down, pointing North. As far as I know there isn't a setting to get EQMOD to change this power-on default (although I have no experience of encoder-equipped mounts).

I am lucky enough to have an observatory, and as long as I maintain power EQMOD 'remembers' the custom park position. However, just to be on the safe side when I start a new session after any kit has been powered off, I run my planetarium software (CdC) and sync position with the mount before carrying out any slews. I can then see on the screen where my mount 'thinks' it is pointing, and if it is North rather than 'sideways-parked' I open the roof and manually point the scope north before then carrying on with my session...

HTH Ady    

Thanks for the info Ady - all the info helps.

Matthew

[Budgie1]

5 hours ago, adyj1 said:

This is also my experience. It isn't NINA causing this, but EQMOD and your mount. If you power off everything between sessions, then when you start EQMOD it will revert to its default start position - and assumes the scope is weights-down, pointing North. As far as I know there isn't a setting to get EQMOD to change this power-on default (although I have no experience of encoder-equipped mounts).

I am lucky enough to have an observatory, and as long as I maintain power EQMOD 'remembers' the custom park position. However, just to be on the safe side when I start a new session after any kit has been powered off, I run my planetarium software (CdC) and sync position with the mount before carrying out any slews. I can then see on the screen where my mount 'thinks' it is pointing, and if it is North rather than 'sideways-parked' I open the roof and manually point the scope north before then carrying on with my session...

HTH Ady    

That's not my experience using EQMOD with APT.

I can park the mount after a session, turn off the power to the mount, have the laptop do a restart for a Windows update. When I next connect the mount to APT, EQMOD works fine from the park position and slews to the required location when I ask CdC to move it. Once pointing roughly at the target using CdC, I get APT to do a plate solve and GoTo, it never moves that far until the plate solving software is happy it's aligned.