Homing the mount

Questions, tips, information and discussions about using the SharpCap Sequencer and Sequence Planner tools
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DirtyRod
Posts: 11
Joined: Mon May 09, 2022 3:08 am

Homing the mount

#1

Post by DirtyRod »

Hey all,

I’ve got a good sequence going that does the captures, autofocuses, etc and at the end of the run I stop imaging, stop guiding, etc and then park the mount. What I can’t figure out how to do is HOME the mount. I’ve tried slewing to Polaris and coordinates in the vicinity but it will end up horizontal because of the slew limit settings and I’d like it to end up vertical in the actual home position.

I’m using CPWI which has the commands to go to the Home Position as well as the Save Alignment and Park Mount both of which move the mount to the actual Home position.

Any suggestions as to how to Home the mount or can someone point me to an option I’ve missed?
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admin
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Re: Homing the mount

#2

Post by admin »

Hi,

the sequencer has a 'Park the Mount' step that is, I think, what you are looking for. The actual position that parking goes to is often configurable in the ASCOM driver options, but the default is usually the home position. If you want to go to the home position in 'unparked' mode, then a park followed by unpark should do the trick.

cheers,

Robin
DirtyRod
Posts: 11
Joined: Mon May 09, 2022 3:08 am

Re: Homing the mount

#3

Post by DirtyRod »

The PARK command is what I'm issuing in the sequencer but it parks the mount in the current location not in the home position. If you park it in CPWI, it asks you whether you want to park in the CURRENT or PREVIOUS location where PREVIOUS is the Home position.
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Re: Homing the mount

#4

Post by admin »

Hi,

ah, OK, ASCOM doesn't work like that - there are three commands basically in ASCOM to do with parking...

* Park - parks the mount to somewhere that the ASCOM driver decides
* Unpark - unparks the mount
* SetPark (may not actually be implemented, and not used by SharpCap ) - sets the parking position to the current position, which *should* be remembered by the ASCOM driver

However, it looks like there are some suggestions that CPWI doesn't do the 'SetPark' command - see https://aptforum.com/phpbb/viewtopic.php?t=3649 for instance.

As far as I can work out, what the CPWI driver is doing (always parking at the current location) is in specification as far as ASCOM is concerned, but not very helpful :(

As you have already noticed, doing a GOTO to somewhere near the pole doesn't help much - it puts the Dec axis in the right place, but RA is out, since it will depend on the sidereal time.

It may be possible to get to the right sort of position by using an Alt/Az goto in the sequencer - for instance, I think if you do a GOTO to a position a little east of the pole as seen from your location, then you should end up in roughly the home position - that is, the alt/az co-ordinates would be

Alt = Your latitude, Az = 1 degree (or 181 in southern hemisphere)

cheers,

Robin
DirtyRod
Posts: 11
Joined: Mon May 09, 2022 3:08 am

Re: Homing the mount

#5

Post by DirtyRod »

Thanks. I'll go back to the suggestion you mentioned below.

Alt = Your latitude, Az = 1 degree (or 181 in southern hemisphere)
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