Date   

Re: Mount RA/DEC slew math

Ray Gralak
 

Why is that? Isn't Alt:0 Az:90 and Alt:0, Az:270 on the same RA plane?
Does the RA axis actually move, or are you relying on where the camera is aiming to detect RA movement? If it is the latter and the camera is not orthogonal, then a 180-degree flip will not be exactly 180 degrees offset from its starting point.

-Ray Gralak
Author of PEMPro
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver


-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of deonb
Sent: Saturday, December 26, 2020 11:39 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] Mount RA/DEC slew math

I'm trying to correct my pier's N/S and E/W positions in my dome, so I stuck a camera in the middle of my scope's lens
cap and ran a tape marker down the length of the dome shutter. I'm then trying to align one axis at a time.

I thought that if I slew from Alt:0 Az:90 to Alt:0, Az:270, the mount will only slew DEC without moving RA. And if the
dome alignment is correct, it should move in a curved track around the dome and come to land in the middle of the
shutter tape on the other side.

That's the theory... In practice what happens is that the RA axis also moves during this slew. Not a lot, but enough to
make my doubt my hypothesis.

Why is that? Isn't Alt:0 Az:90 and Alt:0, Az:270 on the same RA plane?


IC434 first picture for my AP MACH2 and custom built corrected newton #Mach2GTO

Andrea Lucchetti
 

Hi,
I am happy to share my first picture with the mount.
I hope it is not off topic, but please tell me.
After years running an observatory I came back to a nomad set up and I have chosen the MACH2.
The mount is perfect for my set up at 24 kg all included.

It is a Newton corrected and illuminated over a KAF 16803.

At the following link my first image , hope you like it.
https://andrealucchetti.smugmug.com/Astrophotography/Nebulae/i-HDpZ2mD

Attached my set up.

Andrea


Re: Initial GoTo In APCC Pro Cause Nose or Tail Dive

Ray Gralak
 

Hi John,

I just wanted to follow up with you on this issue. Did turning off pointing and tracking rate correction fix the issue?

I am guessing the data for the pointing model you are using may have been gathered with a "bad" version of the ASCOM platform. Specifically, the initial release of the ASCOM 6.5 platform had a severe bug that caused every J2000 to local apparent epoch transformation to have the same RA/Dec. This bug essentially rendered the pointing model useless.

-Ray Gralak
Author of PEMPro
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of John
Sent: Saturday, December 26, 2020 3:55 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Initial GoTo In APCC Pro Cause Nose or Tail Dive

Aloha Ray,

I just sent you the screen shots via email.

Once I slew more than 10 degrees (in either direction), stop the slew, the DEC reads 00 00 00. While slewing and
holding down the left
mouse button, I can see the DEC coordinates actually slewing/changing. But after stopping the slew, the DEC
coordinates revert to 00 00 00
Kind of strange...

After pressing the 'find home' button, the DEC displays the coordinates correctly (after the slew stops) and like what
you're seeing in your screen shot
Hope the screen shots help, thanks!

John



Re: Interesting Mach2 Behavior on Cloudy Nights

Ray Gralak
 

Not sure whether or not I should post the resolution back here, but Roland was able to help me out, and it works great
now without any oscillation.
That's great to hear!

BTW, it would be nice to also post on CN that the issue has been resolved.

-Ray Gralak
Author of PEMPro
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver


-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of deonb
Sent: Sunday, December 27, 2020 2:29 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Interesting Mach2 Behavior on Cloudy Nights

Not sure whether or not I should post the resolution back here, but Roland was able to help me out, and it works great
now without any oscillation.


Re: Meridian Flip Feature Yet?

Ray Gralak
 

Hi Ray,

I need to flip due to the angle of my dome slit, neighbors trees, observatory door, etc. On a mount as advanced as an
AP, there should be a simplistic function that tells the mount the flip immediately without trying to trick it into thinking it
has hit the meridian, this is quite standard on many of the mount brands you mention. It kind of blows me away that
this feature has to be sold on here. If you've always had an environment where meridian flips are not required unless
hours have passed since hitting the meridian, then I understand your feedback. But for those of us that need to flip the
mount before even hitting the meridian, its a different world.
It is easy to automate the flip point. You can do this using the AP V2 ASCOM driver (or the hand controller). You can configure the flip-point so that the mount will flip at the necessary hour angle with a slew to the same RA/Dec.

APCC's meridian limits feature goes much further. It allows you to define different flip points for each declination and pier-side. In operation, this allows worry-free pier flipping and tracking limits to prevent pier collisions without any human intervention. I don't think any of the other mounts you mention have that feature.

-Ray Gralak
Author of PEMPro
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver


-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of ray.palmer@thecosmicartgallery.com
Sent: Sunday, December 27, 2020 2:50 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Meridian Flip Feature Yet?

Hi Chris,

I appreciate your feedback, but nope, I am not new to astrophysics mounts. There are many brand mounts out there
that have a meridian flip feature. You hit one or two buttons and she flips. Many mount owners, due to their
observatory or environment, may only need to flip once the object they are imaging passes the meridian, and AP has
developed a mount that can track for many hours past the meridian.

I need to flip due to the angle of my dome slit, neighbors trees, observatory door, etc. On a mount as advanced as an
AP, there should be a simplistic function that tells the mount the flip immediately without trying to trick it into thinking it
has hit the meridian, this is quite standard on many of the mount brands you mention. It kind of blows me away that
this feature has to be sold on here. If you've always had an environment where meridian flips are not required unless
hours have passed since hitting the meridian, then I understand your feedback. But for those of us that need to flip the
mount before even hitting the meridian, its a different world.

--
Raymond D Palmer
Astronomer
Western Australia
www.MyAstroSpace.com
www.TheCosmicArtGallery.com


Re: Need width and thread size of threaded top end if 1.875” counterweight shafts

M Hambrick
 

Hi Mark

I measure the OD of the threads at 1.083" with a thread pitch of 14 tpi. This is definitely not an ANSI standard thread. Maybe Roland, Howard, or George can comment on the reason this size was chosen.


Re: Precise polar alignment of the azimuth axis

deonb
 

Steven, I’ve used Sharpcap in the past and have done so with the Mach2GTO as well but I’ve recently discovered that my Sharpcap and Polemaster alignment disagrees with each other by over 4 minutes.

I trust the polemaster more since with that I can do 10 minute unguided at 2800mm with Polemaster alignment and about 2 minutes with Sharpcap alignment.

Obviously I need to look into ConeSharp as a result - just saying the SharpCap method of doing polar alignment shouldn’t be trusted blindly.


Re: Meridian Flip Feature Yet?

ray.palmer@...
 

Hi Chris, 

I appreciate your feedback, but nope, I am not new to astrophysics mounts. There are many brand mounts out there that have a meridian flip feature. You hit one or two buttons and she flips. Many mount owners, due to their observatory or environment, may only need to flip once the object they are imaging passes the meridian, and AP has developed a mount that can track for many hours past the meridian. 

I need to flip due to the angle of my dome slit, neighbors trees, observatory door, etc. On a mount as advanced as an AP, there should be a simplistic function that tells the mount the flip immediately without trying to trick it into thinking it has hit the meridian, this is quite standard on many of the mount brands you mention. It kind of blows me away that this feature has to be sold on here. If you've always had an environment where meridian flips are not required unless hours have passed since hitting the meridian, then I understand your feedback. But for those of us that need to flip the mount before even hitting the meridian, its a different world. 

--
Raymond D Palmer
Astronomer
Western Australia
www.MyAstroSpace.com
www.TheCosmicArtGallery.com


Re: Meridian Flip Feature Yet?

Christopher Erickson
 

There must be some communications failures going on here.

I currently have seventeen mounts/scopes using nine different GOTO systems and AFAICT, not one of them has a "do a meridian flip" button or menu command.

And I can't think of a single time that I have ever had to "trick" an AP mount into doing something that it wasn't already capable of doing by design.

The AP mount meridian flip and delay functions work exactly as described in the manual and have always worked perfectly for me and my purposes and as far as I can tell, nothing is missing from their functionality.

My guess is that you are a bit new to AP mounts and their operation. AP mounts do operate a bit differently from most other mounts and if you are already familiar with a different GOTO system, there can be a bit of a re-learning curve. Some time ago I wrote some brief orientation documents for users migrating from Meade, Celestron, Vixen and Losmandy GOTO mounts to the AP way of doing things. Maybe I should find those old documents, upgrade them and put them back on-line someplace. And maybe I should add iOptron, Rainbow, Sidereal Technology and Synta/Skywatcher to the list. I have been sort of waiting on the new AP hand controller firmware before making the effort, since I expect a bunch of new AP functions and commands in the hand controller.

In my mind, the biggest difference between AP and just about everyone else is AP's servo controller "brownout feature" which is capable of saving the exact positions of the axis worm gears and worm wheels to non-volatile memory when it detects that power has been removed from the servo controller. When power is re-applied to the servo controller, it knows the last positions of the worm gears and wheels and knows where it was last at. This design has a lot of benefits but my favorite benefit is that I am doing public outreach and someone kicks out my power cord, I can re-power the mount and do a GOTO to whatever I was just pointing at and it will go back to the object without a hiccup. The CP5 is always connected to the Mach2 abs encoders so it doesn't need the brownout feature that the CP1/2/3/4 needs and since I don't have a Mach2, I can't speak to that detail of the CP5 functionality.

As for meridian flips and meridian delays, I think this is quite possibly the thing that confuses more new AP users than any other feature. I believe there isn't any missing functionality and it works exactly the way I think it should work. The mount will track through the meridian and will flip to the other side during the next GOTO command, as needed. The meridian delay setting tells the mount how far before or past the meridian you want a flip to occur during the next GOTO command. When combined with whatever imaging and mount control software you are using, this works exactly as I would want it to. It won't flip in the middle of an image capture and instead flips between captures.

I hope this helps.

"My advice is always free and worth every penny!"

-Christopher Erickson
Observatory Engineer
Summit Kinetics
Waikoloa, Hawaii


On Sat, Dec 26, 2020 at 10:36 PM <ray.palmer@...> wrote:
Hi Roberto,

I don't think that is what Rolando was referring to. That is a work around that tries to trick the mount into thinking it has hit the meridian. Your settings also may cause the mount to forget its location if the mount is not set back to 0W before powering off. I am looking for the one touch solution, where you hit a button and it flips (like a ton of other mounts do). AP's engineering is the best across the industry in IMHO, but it desperately needs a meridian flip feature. Playing with the settings to trick the mount to flipping is not a meridian flip feature. Note that I don't need a meridian flip because of the meridian's position. Note that the instructions make no reference to a "meridian flip" anywhere when searching for that search term, all they have is "meridian delay" (This is not a meridian flip feature). 
--
Raymond D Palmer
Astronomer
Western Australia
www.MyAstroSpace.com
www.TheCosmicArtGallery.com


Re: Interesting Mach2 Behavior on Cloudy Nights

deonb
 

Not sure whether or not I should post the resolution back here, but Roland was able to help me out, and it works great now without any oscillation.


Re: Meridian Flip Feature Yet?

ray.palmer@...
 

Hi Roberto,

I don't think that is what Rolando was referring to. That is a work around that tries to trick the mount into thinking it has hit the meridian. Your settings also may cause the mount to forget its location if the mount is not set back to 0W before powering off. I am looking for the one touch solution, where you hit a button and it flips (like a ton of other mounts do). AP's engineering is the best across the industry in IMHO, but it desperately needs a meridian flip feature. Playing with the settings to trick the mount to flipping is not a meridian flip feature. Note that I don't need a meridian flip because of the meridian's position. Note that the instructions make no reference to a "meridian flip" anywhere when searching for that search term, all they have is "meridian delay" (This is not a meridian flip feature). 
--
Raymond D Palmer
Astronomer
Western Australia
www.MyAstroSpace.com
www.TheCosmicArtGallery.com


Re: Meridian Flip Feature Yet?

R Botero
 

Raymond

Read the manual: https://www.astro-physics.info/tech_support/mounts/keypad/keypad-manual.pdf 
Page 59 has specific instructions for the Meridian Delay feature. 

Roberto


Mount RA/DEC slew math

deonb
 
Edited

I'm trying to correct my pier's N/S and E/W positions in my dome, so I stuck a camera in the middle of my scope's lens cap and ran a tape marker down the length of the dome shutter. I'm then trying to align one axis at a time.

I thought that if I slew from Alt:0 Az:90 to Alt:0, Az:270, the mount will only slew DEC without moving RA. So if the dome alignment is correct, I should be able to move the lock the RA axis and move the DEC axis manually bit by bit, mark a path on the dome (waiting for the dome to re-slew after each scope movement), then after Meridian flip follow that path down again and the up-and-down path markers should be in alignment. 

That's the theory... In practice what happens is that the RA axis also moves during this slew. Not a lot, but enough to make my doubt my hypothesis. I obviously can't move 2 axis's by hand.

Why is that? Isn't Alt:0 Az:90 and Alt:0, Az:270 on the same RA plane for every Lat?


Re: Meridian Flip Feature Yet?

ray.palmer@...
 

Hi Rolando, 

When I press the +- button, I get a menu that controls guiding speed and slewing speed, but pressing 9 does nothing. However when I press the bottom right corner button (RA / DEC / Rev), I do get a message on the screen that says 0W. Would that be the Meridian flip feature?
--
Raymond D Palmer
Astronomer
Western Australia
www.MyAstroSpace.com
www.TheCosmicArtGallery.com


Re: APCC always on top window

deonb
 

Doh! I was looking for it in every setting dialog I could find.

Thanks!


Re: APCC always on top window

Bill Long
 

Main window, under Program Operation. 

"Keep APCC on top"




From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of deonb <deonb@...>
Sent: Saturday, December 26, 2020 9:25 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: [ap-gto] APCC always on top window
 
How do I disable (make it not-on top) the APCC always-on-top main window?

I figured it out for the AP ASCOM driver, but can't find that setting in APCC.


Re: APCC always on top window

 

it's under setup tab

image.png


On Sat, Dec 26, 2020 at 9:25 PM deonb <deonb@...> wrote:
How do I disable (make it not-on top) the APCC always-on-top main window?

I figured it out for the AP ASCOM driver, but can't find that setting in APCC.



--
Brian 



Brian Valente


APCC always on top window

deonb
 

How do I disable (make it not-on top) the APCC always-on-top main window?

I figured it out for the AP ASCOM driver, but can't find that setting in APCC.


Re: DEC Motor stalls on new Mach2GTO

Roland Christen
 


remove the top Dec cover
Remove the top cover of the DEC motor box, not the Dec axis top. It's the black anodized cover held on with 4 small screws.

Roland


-----Original Message-----
From: Roland Christen via groups.io <chris1011@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>; photo@... <photo@...>
Sent: Sat, Dec 26, 2020 7:31 pm
Subject: Re: [ap-gto] DEC Motor stalls on new Mach2GTO

Loosen all 4 clutch knobs. Move the Dec axis manually from one stop to the other. See if you can feel anything that prevents the axis from moving easily.

Then try moving the mount via the buttons at 1200x in Dec with clutches still loose. The motor should turn easily.
If it does not, remove the top Dec cover and look inside where the motor and belt reduction is. Can you turn the motor with the buttons now?

Send me the answer direct to chris1011@....

Roland Christen





-----Original Message-----
From: Luca Marinelli <photo@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sat, Dec 26, 2020 7:16 pm
Subject: Re: [ap-gto] DEC Motor stalls on new Mach2GTO

Thanks a lot for the quick reply, Roland. I am pretty sure I mounted the dovetail with the arrow pointing forward. The USB and power port are in the back of the scope, not on the side. See the attached picture.

Also, both N and S movements result in motor stalls, not just in one direction.

Thanks again,

Luca




On Dec 26, 2020, at 8:01 PM, Roland Christen via groups.io <chris1011@...> wrote:


It sounds like you are hitting the internal hard limit. You probably have the scope mounted at 90 degrees from the arrow on the top of the Dec mounting plate. Remove your scope and dovetail and look at the mounting plate. You will se a long arrow. This is the direction that your scope must point. You cannot mount it at 90 degrees or you simply run out of Dec motion when pointing south and the axis will hit the hard stop and the motors will stall with yellow light coming on.

Can you post a picture showing the scope pointing at the north pole?

Roland Christen
Astro-Physics Inc.



-----Original Message-----
From: Luca Marinelli <photo@...>
To: main@ap-gto.groups.io
Sent: Sat, Dec 26, 2020 6:16 pm
Subject: [ap-gto] DEC Motor stalls on new Mach2GTO

Today I replaced the Mach1 in the observatory with the new Mach2 I received a few days ago. I have a Tak FSQ106 mounted on the Mach2 and it balanced without any problems. I tested a slew and everything worked fine. I then started to set up the Meridian limit in APCC Pro and after sending the scope to the Southern horizon (-15 degrees DEC) I started experiencing motor stalls. The mount makes a whirring/grinding noise when trying to slew in DEC and APCC communication window shows motor stall condition. The light on the CP5 turns amber. I measured the voltage out of the power supply and it is correct (24.94V). I also replaced the power supply with the power supply i used with the Mach1 and the same thing happened. To test the motor cable, I swapped DEC and RA cables and the fault was still on the DEC axis. I removed the telescope and tried slewing the empty mount in DEC, to no avail (motor stalls). 

APCC Pro version: 1.8.8.11
CP5 firmware: VCP5-P02-08
Encoder version: A02-08

Is there anything obvious I am missing?

thanks,

Luca
 

--
Roland Christen
Astro-Physics

--
Roland Christen
Astro-Physics

--
Roland Christen
Astro-Physics


Re: DEC Motor stalls on new Mach2GTO

Roland Christen
 

Loosen all 4 clutch knobs. Move the Dec axis manually from one stop to the other. See if you can feel anything that prevents the axis from moving easily.

Then try moving the mount via the buttons at 1200x in Dec with clutches still loose. The motor should turn easily.
If it does not, remove the top Dec cover and look inside where the motor and belt reduction is. Can you turn the motor with the buttons now?

Send me the answer direct to chris1011@....

Roland Christen





-----Original Message-----
From: Luca Marinelli <photo@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sat, Dec 26, 2020 7:16 pm
Subject: Re: [ap-gto] DEC Motor stalls on new Mach2GTO

Thanks a lot for the quick reply, Roland. I am pretty sure I mounted the dovetail with the arrow pointing forward. The USB and power port are in the back of the scope, not on the side. See the attached picture.

Also, both N and S movements result in motor stalls, not just in one direction.

Thanks again,

Luca




On Dec 26, 2020, at 8:01 PM, Roland Christen via groups.io <chris1011@...> wrote:


It sounds like you are hitting the internal hard limit. You probably have the scope mounted at 90 degrees from the arrow on the top of the Dec mounting plate. Remove your scope and dovetail and look at the mounting plate. You will se a long arrow. This is the direction that your scope must point. You cannot mount it at 90 degrees or you simply run out of Dec motion when pointing south and the axis will hit the hard stop and the motors will stall with yellow light coming on.

Can you post a picture showing the scope pointing at the north pole?

Roland Christen
Astro-Physics Inc.



-----Original Message-----
From: Luca Marinelli <photo@...>
To: main@ap-gto.groups.io
Sent: Sat, Dec 26, 2020 6:16 pm
Subject: [ap-gto] DEC Motor stalls on new Mach2GTO

Today I replaced the Mach1 in the observatory with the new Mach2 I received a few days ago. I have a Tak FSQ106 mounted on the Mach2 and it balanced without any problems. I tested a slew and everything worked fine. I then started to set up the Meridian limit in APCC Pro and after sending the scope to the Southern horizon (-15 degrees DEC) I started experiencing motor stalls. The mount makes a whirring/grinding noise when trying to slew in DEC and APCC communication window shows motor stall condition. The light on the CP5 turns amber. I measured the voltage out of the power supply and it is correct (24.94V). I also replaced the power supply with the power supply i used with the Mach1 and the same thing happened. To test the motor cable, I swapped DEC and RA cables and the fault was still on the DEC axis. I removed the telescope and tried slewing the empty mount in DEC, to no avail (motor stalls). 

APCC Pro version: 1.8.8.11
CP5 firmware: VCP5-P02-08
Encoder version: A02-08

Is there anything obvious I am missing?

thanks,

Luca
 

--
Roland Christen
Astro-Physics

--
Roland Christen
Astro-Physics

4641 - 4660 of 79787