Needing re-do the PE after updating 1200 cp3 L chip to V chip.


wildwood7711@...
 

Hi All, Can I do my PE in the house? As long as the mount is pointed to the Celestial Equator and near the Meridian (Park 3?). I guess I just power the mount and go right into the tools menu and choose 1.) PEM and start   Roland's step by step procedure w/ PEMPro. No where does it state the scope must be tracking on a object. Thanks, Mike


W Hilmo
 

PEMPro will need to be able to track a star in the camera’s field of view.  If it can’t do this, then it won’t work.

 

So no, you cannot do this in the house.  You need to be out under a clear, dark sky.

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, February 3, 2018 10:12 AM
To: ap-gto@...
Subject: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.

 

 

Hi All, Can I do my PE in the house? As long as the mount is pointed to the Celestial Equator and near the Meridian (Park 3?). I guess I just power the mount and go right into the tools menu and choose 1.) PEM and start   Roland's step by step procedure w/ PEMPro. No where does it state the scope must be tracking on a object. Thanks, Mike


Joe Zeglinski
 

Hi,
 
    I suspect you may dread being out there in the cold winter night, capturing raw data for the curve. Luckily, sampling 6 to 8 raw data cycles will take over an hour anyway,  and once started, doesn’t require your presence at the mount – good time for an indoor coffee break. Later, even the PEC analysis and final curve fitting can be leisurely done indoors as well, then just upload the result into the CPx  mount controller.
 
    Programs that calculate the PEC wave pattern on the gear train teeth variations, need “some kind” of reference.
A bouncing star is ideal because it is simple. I suppose it might be theoretically possible, but impractical –  to do the PEC curve generation in daylight, or even in the house, using a commonly available “simulated star” or compare successive frames of a room scene (or a precisely printed target), for their shifting. But it would be less precise and require much more computer resource. Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking, PA, cross winds, and drift from the process – but not a present capability in any PEC generating software I know of.
 
    So, PEC generation can only be done with a camera centered on a reference star.
 
    Luckily, PemPro doesn’t require a perfect polar alignment to do this part of the job – it compensates internally for many things, including an arbitrarily CCD rotation, although a reasonably close CCD rotational alignment with the axes, and a good initial mount polar alignment would probably help it producing a slightly more accurate curve. But such detail isn’t really necessary, since normal “seeing conditions” could affect guiding more, in spite of a good PEC curve. But, everything helps.
 
    PEC is only needed for imaging and not for visual use with the mount, since visual use won’t see minor position variations. Since you will be doing it soon anyway, just be patient and leave the PEC curve generation for that first night out there under the stars with your CCD. PemPro makes it easy and indeed fun to do.
 
Joe 


Roland Christen
 


Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking,
The whole idea of generating a PE curve is to measure tracking, so if you aim the camera at the pole, you won't get any data. But not to worry, PEMPro automatically sends your mount to the celestial equator, where the tracking rate of a star is almost exactly sidereal. Any departure measured by PEMPro is then the PE.

Rolando


-----Original Message-----
From: 'Joseph Zeglinski' J.Zeglinski@... [ap-gto]
To: ap-gto
Sent: Sat, Feb 3, 2018 1:16 pm
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.



Hi,
 
    I suspect you may dread being out there in the cold winter night, capturing raw data for the curve. Luckily, sampling 6 to 8 raw data cycles will take over an hour anyway,  and once started, doesn’t require your presence at the mount – good time for an indoor coffee break. Later, even the PEC analysis and final curve fitting can be leisurely done indoors as well, then just upload the result into the CPx  mount controller.
 
    Programs that calculate the PEC wave pattern on the gear train teeth variations, need “some kind” of reference.
A bouncing star is ideal because it is simple. I suppose it might be theoretically possible, but impractical –  to do the PEC curve generation in daylight, or even in the house, using a commonly available “simulated star” or compare successive frames of a room scene (or a precisely printed target), for their shifting. But it would be less precise and require much more computer resource. Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking, PA, cross winds, and drift from the process – but not a present capability in any PEC generating software I know of.
 
    So, PEC generation can only be done with a camera centered on a reference star.
 
    Luckily, PemPro doesn’t require a perfect polar alignment to do this part of the job – it compensates internally for many things, including an arbitrarily CCD rotation, although a reasonably close CCD rotational alignment with the axes, and a good initial mount polar alignment would probably help it producing a slightly more accurate curve. But such detail isn’t really necessary, since normal “seeing conditions” could affect guiding more, in spite of a good PEC curve. But, everything helps.
 
    PEC is only needed for imaging and not for visual use with the mount, since visual use won’t see minor position variations. Since you will be doing it soon anyway, just be patient and leave the PEC curve generation for that first night out there under the stars with your CCD. PemPro makes it easy and indeed fun to do.
 
Joe 



Steven
 

Wade, 

you've got to 'calibrate' your mount to PemPro to get the results you need. That will require a real star. But after you do that, you can sit in a warm room and 'watch the show' and do the rest of it there. A star is needed. Don't forget to use the Calibration Wizard, and before doing that, set up the Mount Wizard to set the necessary parameters of your mount so PemPro knows what it's looking at. All pretty easy and straight forward really. But you need a star.

Steve E
NZ




From: ap-gto@... on behalf of 'Wade Hilmo' y.groups@... [ap-gto]
Sent: Saturday, 3 February 2018 1:19 p.m.
To: ap-gto@...
Subject: RE: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
 
 

PEMPro will need to be able to track a star in the camera’s field of view.  If it can’t do this, then it won’t work.

 

So no, you cannot do this in the house.  You need to be out under a clear, dark sky.

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, February 3, 2018 10:12 AM
To: ap-gto@...
Subject: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.

 

 

Hi All, Can I do my PE in the house? As long as the mount is pointed to the Celestial Equator and near the Meridian (Park 3?). I guess I just power the mount and go right into the tools menu and choose 1.) PEM and start   Roland's step by step procedure w/ PEMPro. No where does it state the scope must be tracking on a object. Thanks, Mike


Joe Zeglinski
 

Rolando,
 
    I was “imagining” ... that it could be possible, (some day, with some new PemPro approach), to just watch Polaris jump up & down , even with the mount at relative standstill. Polaris is an easy, almost stationary target, for the hour of curve raw data capture. Tracking the pole might be (almost) unnecessary. If Polaris drifts a tad sideway, the program wouldn’t care, since it is looking for absolute amplitudes, not celestial drift. In effect, Polaris acts like a “simulated star accessory device”, some of us use. All we are after is seeing the “amplitude” and direction of the star’s perfectly vertical jitter, to determine the period in each cycle, and amount of drift caused by the two spur gears. It wouldn’t even be affected by scope load imbalance and other mount dynamics. Following the sky across the meridian would become unnecessary, by such method.
 
    Once the PEC curve is generated, tracking becomes second nature – it wouldn’t really be needed “during” data gathering.
Or, possibly I haven't clearly explained my idea and we are not understanding each other.
 
No matter – just a thought, for future directions.
Joe

From: chris1011@... [ap-gto]
Sent: Saturday, February 3, 2018 2:54 PM
To: ap-gto@...
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking,
The whole idea of generating a PE curve is to measure tracking, so if you aim the camera at the pole, you won't get any data. But not to worry, PEMPro automatically sends your mount to the celestial equator, where the tracking rate of a star is almost exactly sidereal. Any departure measured by PEMPro is then the PE.

Rolando
 
 


MCDERMOTT MICHAEL <wildwood7711@...>
 

Wow, thanks for the all the information. Just maybe another warm (50 degree) night will be coming up soon and clear. I just downloaded PEMPro 3. Looking forward to this! Who says you can't teach a old dog new tricks!  -Mike


On Saturday, February 3, 2018 2:00 PM, "Steven Elliott steven447@... [ap-gto]" wrote:


 
Wade, 
you've got to 'calibrate' your mount to PemPro to get the results you need. That will require a real star. But after you do that, you can sit in a warm room and 'watch the show' and do the rest of it there. A star is needed. Don't forget to use the Calibration Wizard, and before doing that, set up the Mount Wizard to set the necessary parameters of your mount so PemPro knows what it's looking at. All pretty easy and straight forward really. But you need a star.
Steve E
NZ



From: ap-gto@... on behalf of 'Wade Hilmo' y.groups@... [ap-gto]
Sent: Saturday, 3 February 2018 1:19 p.m.
To: ap-gto@...
Subject: RE: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
 
 
PEMPro will need to be able to track a star in the camera’s field of view.  If it can’t do this, then it won’t work.
 
So no, you cannot do this in the house.  You need to be out under a clear, dark sky.
 
From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, February 3, 2018 10:12 AM
To: ap-gto@...
Subject: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
 
 
Hi All, Can I do my PE in the house? As long as the mount is pointed to the Celestial Equator and near the Meridian (Park 3?). I guess I just power the mount and go right into the tools menu and choose 1.) PEM and start   Roland's step by step procedure w/ PEMPro. No where does it state the scope must be tracking on a object. Thanks, Mike



Roland Christen
 


just watch Polaris jump up & down
Polaris won't jump up and down, even if you push the forward reverse buttons on the keypad at 16x.

Rolando


-----Original Message-----
From: 'Joseph Zeglinski' J.Zeglinski@... [ap-gto]
To: ap-gto
Sent: Sat, Feb 3, 2018 2:25 pm
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.



Rolando,
 
    I was “imagining” ... that it could be possible, (some day, with some new PemPro approach), to just watch Polaris jump up & down , even with the mount at relative standstill. Polaris is an easy, almost stationary target, for the hour of curve raw data capture. Tracking the pole might be (almost) unnecessary. If Polaris drifts a tad sideway, the program wouldn’t care, since it is looking for absolute amplitudes, not celestial drift. In effect, Polaris acts like a “simulated star accessory device”, some of us use. All we are after is seeing the “amplitude” and direction of the star’s perfectly vertical jitter, to determine the period in each cycle, and amount of drift caused by the two spur gears. It wouldn’t even be affected by scope load imbalance and other mount dynamics. Following the sky across the meridian would become unnecessary, by such method.
 
    Once the PEC curve is generated, tracking becomes second nature – it wouldn’t really be needed “during” data gathering.
Or, possibly I haven't clearly explained my idea and we are not understanding each other.
 
No matter – just a thought, for future directions.
Joe
From: chris1011@... [ap-gto]
Sent: Saturday, February 3, 2018 2:54 PM
To: ap-gto@...
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking,
The whole idea of generating a PE curve is to measure tracking, so if you aim the camera at the pole, you won't get any data. But not to worry, PEMPro automatically sends your mount to the celestial equator, where the tracking rate of a star is almost exactly sidereal. Any departure measured by PEMPro is then the PE.

Rolando
 
 



Worsel
 

Mike

An approach  that DOES allow inside use is remote control of your outside PC.  This is quite common for permanently mounted systems.  

The inside PC connects to the outside PC using a home network.  This can be either via WiFi (can be slow at times) or via hardwired cable (requires a router or ad-hoc connection) or via household wiring (requires Powerline adapters).  Regardless of the network, there are any number of suitable software packages, including TightVNC, MS Remote Desktop, TeamViewe, RealVNC.  We each have our preferences.  There is no perfect approach...if there was, we would all have the same setup...just like telescopes!


Bryan


Christopher Erickson
 

Just another one of my random product brainstorming ideas here.

AP develops an absolute encoder assembly that can be placed on the separation dovetail of an AP mount's RA axis (900, 1100, 1200, 1600, 3600) when the mount is separated in half. Combined with a special AP program, will automatically read the PE of the RA gearing and write the PEM curve to a CP4.

No sky, stars, seeing, camera or other bits required and can be done inside at any time, day or night.

AP can offer the fully automatic  "bench-PEM-programmer" for sale and/or lease. Use it and optionally return it for a partial deposit refund.

And if it is thin and has dovetails on both sides, can possibly be left in place on 900 and 1200 mounts for high-precision RA tracking and positioning.

Just a random idea.

-Christopher Erickson
Observatory engineer
Waikoloa, HI 96738
www.summitkinetics.com
   

On Feb 3, 2018 10:52 AM, "chris1011@... [ap-gto]" <ap-gto@...> wrote:



just watch Polaris jump up & down
Polaris won't jump up and down, even if you push the forward reverse buttons on the keypad at 16x.

Rolando


-----Original Message-----
From: 'Joseph Zeglinski' J.Zeglinski@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Sat, Feb 3, 2018 2:25 pm
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.



Rolando,
 
    I was “imagining” ... that it could be possible, (some day, with some new PemPro approach), to just watch Polaris jump up & down , even with the mount at relative standstill. Polaris is an easy, almost stationary target, for the hour of curve raw data capture. Tracking the pole might be (almost) unnecessary. If Polaris drifts a tad sideway, the program wouldn’t care, since it is looking for absolute amplitudes, not celestial drift. In effect, Polaris acts like a “simulated star accessory device”, some of us use. All we are after is seeing the “amplitude” and direction of the star’s perfectly vertical jitter, to determine the period in each cycle, and amount of drift caused by the two spur gears. It wouldn’t even be affected by scope load imbalance and other mount dynamics. Following the sky across the meridian would become unnecessary, by such method.
 
    Once the PEC curve is generated, tracking becomes second nature – it wouldn’t really be needed “during” data gathering.
Or, possibly I haven't clearly explained my idea and we are not understanding each other.
 
No matter – just a thought, for future directions.
Joe
From: chris1011@... [ap-gto]
Sent: Saturday, February 3, 2018 2:54 PM
To: ap-gto@...
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V chip.
Might even be able to do this with a camera targeted on Polaris, to eliminate the complications of  tracking,
The whole idea of generating a PE curve is to measure tracking, so if you aim the camera at the pole, you won't get any data. But not to worry, PEMPro automatically sends your mount to the celestial equator, where the tracking rate of a star is almost exactly sidereal. Any departure measured by PEMPro is then the PE.

Rolando
 
 





MCDERMOTT MICHAEL <wildwood7711@...>
 

I have a QHY8, also have a Orion 80ed and a Astro-Physics 178 and a Meade 14" does it matter which scope would give the best PE readings. Also one more question if I change the scope after I do the PE, do I need to do it again?


On Saturday, February 3, 2018 3:03 PM, "bryancashion@... [ap-gto]" wrote:


 
Mike

An approach  that DOES allow inside use is remote control of your outside PC.  This is quite common for permanently mounted systems.  

The inside PC connects to the outside PC using a home network.  This can be either via WiFi (can be slow at times) or via hardwired cable (requires a router or ad-hoc connection) or via household wiring (requires Powerline adapters).  Regardless of the network, there are any number of suitable software packages, including TightVNC, MS Remote Desktop, TeamViewe, RealVNC.  We each have our preferences.  There is no perfect approach...if there was, we would all have the same setup...just like telescopes!


Bryan



Roland Christen
 

Scope has no effect on PE. Periodic error is a function of the worm, not of anything else attached to the mount. Best data of course is taken with the scope of the longest focal length, BUT sometimes an SCT will introduce its own errors such as when the mirror shifts, and you definitely don't want bogus data for PE correction. In your case either the 178 refractor or the 80mm refractor would give better data (more consistent data).

Rolando



-----Original Message-----
From: MCDERMOTT MICHAEL wildwood7711@... [ap-gto]
To: ap-gto
Sent: Sat, Feb 3, 2018 4:07 pm
Subject: Re: [ap-gto] Re: Needing re-do the PE after updating 1200 cp3 L chip to V chip.



I have a QHY8, also have a Orion 80ed and a Astro-Physics 178 and a Meade 14" does it matter which scope would give the best PE readings. Also one more question if I change the scope after I do the PE, do I need to do it again?


On Saturday, February 3, 2018 3:03 PM, "bryancashion@... [ap-gto]" gto@...> wrote:


 
Mike

An approach  that DOES allow inside use is remote control of your outside PC.  This is quite common for permanently mounted systems.  

The inside PC connects to the outside PC using a home network.  This can be either via WiFi (can be slow at times) or via hardwired cable (requires a router or ad-hoc connection) or via household wiring (requires Powerline adapters).  Regardless of the network, there are any number of suitable software packages, including TightVNC, MS Remote Desktop, TeamViewe, RealVNC.  We each have our preferences.  There is no perfect approach...if there was, we would all have the same setup...just like telescopes!


Bryan





W Hilmo
 

You are technically right that the operator doesn't need to stay outside
with the mount while PEMPro is doing its thing. But given the following
context from the original question:



"No where does it state the scope must be tracking on a object"



The question is asking whether the *mount* needs to be outside or not. It
does. Or at least it needs a clear view to the stars in the appropriate
areas of the sky.



From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, February 3, 2018 12:01 PM
To: ap-gto@...
Subject: Re: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to
V chip.





Wade,

you've got to 'calibrate' your mount to PemPro to get the results you need.
That will require a real star. But after you do that, you can sit in a warm
room and 'watch the show' and do the rest of it there. A star is needed.
Don't forget to use the Calibration Wizard, and before doing that, set up
the Mount Wizard to set the necessary parameters of your mount so PemPro
knows what it's looking at. All pretty easy and straight forward really. But
you need a star.

Steve E
NZ



_____

From: ap-gto@... <ap-gto@...> on behalf of 'Wade
Hilmo' y.groups@... [ap-gto] <ap-gto@...>
Sent: Saturday, 3 February 2018 1:19 p.m.
To: ap-gto@...
Subject: RE: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to
V chip.





PEMPro will need to be able to track a star in the camera's field of view.
If it can't do this, then it won't work.



So no, you cannot do this in the house. You need to be out under a clear,
dark sky.



From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, February 3, 2018 10:12 AM
To: ap-gto@...
Subject: [ap-gto] Needing re-do the PE after updating 1200 cp3 L chip to V
chip.





Hi All, Can I do my PE in the house? As long as the mount is pointed to the
Celestial Equator and near the Meridian (Park 3?). I guess I just power the
mount and go right into the tools menu and choose 1.) PEM and start
Roland's step by step procedure w/ PEMPro. No where does it state the scope
must be tracking on a object. Thanks, Mike


Suresh Mohan
 

You need to track on a star . That too choose a day with good seeing 
Suresh


On 03-Feb-2018, at 11:42 PM, wildwood7711@... [ap-gto] <ap-gto@...> wrote:

 

Hi All, Can I do my PE in the house? As long as the mount is pointed to the Celestial Equator and near the Meridian (Park 3?). I guess I just power the mount and go right into the tools menu and choose 1.) PEM and start   Roland's step by step procedure w/ PEMPro. No where does it state the scope must be tracking on a object. Thanks, Mike