Date
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MACH1 GTO Merdian Flip #Keypad
Ken Murfitt
Hello!
While imaging the Crescent Nebula a few nights back, I rang into a snag when attempting a meridian flip from the Keypad.
While imaging the Crescent Nebula a few nights back, I rang into a snag when attempting a meridian flip from the Keypad.
I tried to perform a meridian flip from the Keypad by setting RA/DEC/REV -> Meridian 2E, 1E, 0W, 1W, 2W in that order. Each time I attempted to
"re-go to" the Crescent nebula but the mount would not perform a merdian flip.
The scope was almost upright on the West side - well within the hour of passing the meridian.
I used the Tour -> Common Object Names to select the Crescent nebula. I later tried selecting NGC 6888 directly but the mount would not flip.
The Keypad Mount Type is set to MACH1.
Auto-Connect is set to EXT - my setup connects with Stellarium.
All other operations between the keypad, Stellarium, PHD2 and the mount seemed to be working fine.
The Keypad is relatively new (2018 model - firmware rev 4.19.3) and so I don't suspect the battery is the problem - I get no 'symptoms' of low battery ("object below horizon" etc).
Any thoughts on how to achieve a meridian flip from the Keypad please? Should I have set something from the Astro-Physics driver instead?
The Keypad is relatively new (2018 model - firmware rev 4.19.3) and so I don't suspect the battery is the problem - I get no 'symptoms' of low battery ("object below horizon" etc).
Any thoughts on how to achieve a meridian flip from the Keypad please? Should I have set something from the Astro-Physics driver instead?
Eventually I slewed the mount manually to perform the "flip".
Thanks for any pointers.
Roland Christen
Meridian delay does not perform a meridian flip. Those are two different things. Normally the mount will continue to track past the meridian (overhead point) until you send a GoTo. Then it will flip sides. The mount can also be set up to stop tracking at the meridian by setting the limits.
If the mount does not flip when you issue a GoTo after it has passed the meridian, then it is highly likely that the clock time is set wrong. The meridian is calculated from your local time/date/location. In the keypad main Menu pressing 4 = Time/LST will bring up your local time and LST which is the calculated Meridian Right Ascension value. (LST = Local Sidereal Time). That RA value is the point where the mount will flip sides when a GoTo is issued. So, that is a check on the operation of the mount that you need to be familiar with. Simply compare the calculated value and compare it to where your planetarium program says the meridian is. Also check the local clock time to make sure it is not set to the wrong value. Clock time is shown as military time (example 1pm = 1300 hours).
Rolando
-----Original Message-----
From: Ken M <kmurfitt@...>
To: main@ap-gto.groups.io
Sent: Thu, Jul 23, 2020 12:20 pm
Subject: [ap-gto] MACH1 GTO Merdian Flip #Keypad
From: Ken M <kmurfitt@...>
To: main@ap-gto.groups.io
Sent: Thu, Jul 23, 2020 12:20 pm
Subject: [ap-gto] MACH1 GTO Merdian Flip #Keypad
Hello!
While imaging the Crescent Nebula a few nights back, I rang into a snag when attempting a meridian flip from the Keypad.
While imaging the Crescent Nebula a few nights back, I rang into a snag when attempting a meridian flip from the Keypad.
I tried to perform a meridian flip from the Keypad by setting RA/DEC/REV -> Meridian 2E, 1E, 0W, 1W, 2W in that order. Each time I attempted to
"re-go to" the Crescent nebula but the mount would not perform a merdian flip.
The scope was almost upright on the West side - well within the hour of passing the meridian.
I used the Tour -> Common Object Names to select the Crescent nebula. I later tried selecting NGC 6888 directly but the mount would not flip.
The Keypad Mount Type is set to MACH1.
Auto-Connect is set to EXT - my setup connects with Stellarium.
All other operations between the keypad, Stellarium, PHD2 and the mount seemed to be working fine.
The Keypad is relatively new (2018 model - firmware rev 4.19.3) and so I don't suspect the battery is the problem - I get no 'symptoms' of low battery ("object below horizon" etc).
Any thoughts on how to achieve a meridian flip from the Keypad please? Should I have set something from the Astro-Physics driver instead?
The Keypad is relatively new (2018 model - firmware rev 4.19.3) and so I don't suspect the battery is the problem - I get no 'symptoms' of low battery ("object below horizon" etc).
Any thoughts on how to achieve a meridian flip from the Keypad please? Should I have set something from the Astro-Physics driver instead?
Eventually I slewed the mount manually to perform the "flip".
Thanks for any pointers.
Hi Ken,
I’m pretty sure I know exactly what is wrong. The keypad performs the meridian delay by “fooling” the clock in the GTOCPx control box. The driver is probably undoing the keypad’s clock fooling commands.
There are two solutions. Each will work, but I don’t advise mixing them. Choose one and use that method exclusively.
1. In the driver, Uncheck the boxes to “…keep mount time synced to PC time (recommended)” That may not be a perfect quote. Then you can do meridian delay with the keypad. Just be sure to undo it with the keypad as well.
2. Set meridian delay in the driver instead of the keypad. You can then still use the keypad for your GoTo.
The next major keypad version will use the same method as the driver for meridian delay, so the problem will go away.
Mag. 7 Skies!
Howard Hedlund
Astro-Physics, Inc.
Phone: 815-315-7015
Please include this e-mail with your response.
P Consider the environment before printing this e-mail.
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io]
On Behalf Of Ken Murfitt
Sent: Thursday, July 23, 2020 13:06
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
Sent: Thursday, July 23, 2020 13:06
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
I shall check those things the next time I am out, thanks.
Roland Christen
Whenever the keypad is set to EXT mode, it is advisable to always use the external app to control the mount, and that includes setting Meridian delay. In EXT you are initializing the mount via an external app and should always use that app for any setup commands, NOT the keypad. Don't use the keypad for anything other than moving around via the buttons or sending the mount to a star or object from the keypad Objects menu.
When you use EXT mode, you are defining the external app to be the main controlling element, and the keypad is then secondary.
Rolando
-----Original Message-----
From: Howard Hedlund <howard@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Thu, Jul 23, 2020 2:36 pm
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
From: Howard Hedlund <howard@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Thu, Jul 23, 2020 2:36 pm
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
Hi Ken,
I’m pretty sure I know exactly what is wrong. The keypad performs the meridian delay by “fooling” the clock in the GTOCPx control box. The driver is probably
undoing the keypad’s clock fooling commands.
There are two solutions. Each will work, but I don’t advise mixing them. Choose one and use that method exclusively.
1.
In the driver, Uncheck the boxes to “…keep mount time synced to PC time (recommended)” That may not be a perfect quote. Then you can do meridian
delay with the keypad. Just be sure to undo it with the keypad as well.
2.
Set meridian delay in the driver instead of the keypad. You can then still use the keypad for your GoTo.
The next major keypad version will use the same method as the driver for meridian delay, so the problem will go away.
Mag. 7 Skies!
Howard Hedlund
Astro-Physics, Inc.
Phone: 815-315-7015
Please include this e-mail with your response.
P
Consider the environment before printing this e-mail.
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io]
On Behalf Of Ken Murfitt
Sent: Thursday, July 23, 2020 13:06
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
Sent: Thursday, July 23, 2020 13:06
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] MACH1 GTO Merdian Flip #Keypad
I shall check those things the next time I am out, thanks.
Ken Murfitt
Ah, terrific. I had read the meridian delay instructions quite carefully in the GTOCP4 and Keypad manuals, and how it was achieved internally and surmised that probably it was something overriding the keypad meridian delay feature. I always feel like I am pushing my luck when using the Keypad on top of whatever other software might be communicating with the mount - I can work with that if I know where the use-case boundaries are. Thanks!