Date   

Re: Mount connected and not tracking

Roland Christen
 

Could be the mount is set to STOP rather than to Sidereal rate. The ASCOM driver would be able to tell what is going on and where the mount is set.

Rolando



-----Original Message-----
From: 'Christopher Erickson' christopher.k.erickson@... [ap-gto]
To: ap-gto
Sent: Mon, Sep 25, 2017 7:43 pm
Subject: RE: [ap-gto] Re: Mount connected and not tracking



There could be many possible reasons.
 
Can you tell us more about your setup?
 
What software?
 
What hardware?
 
What OTA and remotely-controlled accessories?
 
Software configurations?
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 2:23 AM
To: ap-gto@...
Subject: [ap-gto] Re: Mount connected and not tracking

sorry i am more precise:

My 1100 Gto mount in remote has this new behaviour:
If i send the mount to an object it lacks the object because after having slewed for a while turns in connected status but not tracking  and Skyx shows a bad position ; Why? The problem can be caused from something that blocks the mount? The cables inside the mount?
Carmine


Virus-free. www.avg.com



Re: Mount connected and not tracking

Christopher Erickson
 

There could be many possible reasons.
 
Can you tell us more about your setup?
 
What software?
 
What hardware?
 
What OTA and remotely-controlled accessories?
 
Software configurations?
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 



From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 2:23 AM
To: ap-gto@...
Subject: [ap-gto] Re: Mount connected and not tracking

sorry i am more precise:

My 1100 Gto mount in remote has this new behaviour:
If i send the mount to an object it lacks the object because after having slewed for a while turns in connected status but not tracking  and Skyx shows a bad position ; Why? The problem can be caused from something that blocks the mount? The cables inside the mount?
Carmine


Virus-free. www.avg.com


Re: PEM Files Upoloaded: Need sanity check

Jerome Yesavage
 

Wow, spinning my carefully calibrated prayer wheel tonight hoping I get this right from scratch. 


APCC pro and APT 3.33 any experience?

t.hellwing@...
 

Hi all,

Do anyone have good or bad experience with the imaging software APT (Astrophotography Tool) especially with the new version 3.33 in combination with APCC?

What would be your recommendation for other imaging software in combination wit APPC pro?

It seems that APT 3.33 and APCC pro is running not very stable (may be only in my case).

Regards
Thomas


Re: APCC + SkySafari?

Christopher Erickson
 

Having APCC between Sky Safari Plus/Pro and the mount is an interesting idea.
 
You would need a way to make the PC look like and respond like the CP4's WiFi/Ethernet connections.  Basically to offer incoming mount control connections on TCP and/or UDP port 23 on the PC's IP address.
 
This would be a request to Ray to add that capability to APCC.
 
It would have network security concerns for your PC running APCC.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 



From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 7:45 AM
To: ap-gto@...
Subject: Re: [ap-gto] APCC + SkySafari?

Hello Christopher,

Thanks a lot for your response.

>As has been discussed in great detail recently, WiFi on the CP4 isn't currently a  fully-reliable connectivity option.  Of course WiFi is NEVER going to be a fully-reliable connectivity option for anything.  That's just the nature of WiFi anyway.
 
>If you want 99.999% reliable communications with your mount, use RS-232 or Ethernet connectivity.  Don't use WiFi or USB.

I completely agree and understand the limitation of wifi connection. I use RS-232 between my PC and my mount. I believe the problem with wireless connection in this case is that I am not able to re-connect to the mount. The mount wifi is up (I can open it in my browser) and so is my phone's. Restarting phone does not help, restarting mount does. This tells me that GTO CP4 is somehow left in a state that does not allow this connection anymore. Serial connection to the mount continues to work fine when this happens. If there is a way to collect logs, I will be more than happy to provide it if that helps.

My main point however was more in terms of being able to use APCC Pro as the point of interface between SkySafari or any other mobile software/hand control and the mount. Seems like this should be possible. I was wondering if anyone had tried it or have any suggestions.

Regards
Hemant




On Sun, Sep 24, 2017 at 2:50 PM, 'Christopher Erickson' christopher.k.erickson@... [ap-gto] <ap-gto@...> wrote:
 

As has been discussed in great detail recently, WiFi on the CP4 isn't currently a  fully-reliable connectivity option.  Of course WiFi is NEVER going to be a fully-reliable connectivity option for anything.  That's just the nature of WiFi anyway.
 
If you want 99.999% reliable communications with your mount, use RS-232 or Ethernet connectivity.  Don't use WiFi or USB.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, September 24, 2017 7:27 AM
To: ap-gto@...
Subject: [ap-gto] APCC + SkySafari?

Hello all,

I use Sky Safari to control my GTO mount. I have tried two ways of connecting Sky Safari to GTO:

1. Using GTO's IP address (port 23) and setting mount type to Astro-Physics GTO

2. Using The Skyx (My PC's IP address and The Skyx server port) and setting the mount to Paramount+TheSkyx

When I connect directly to GTO, the connection works most of the time but disconnects occasionally and the only solution then is to power cycle the mount. Not sure if anyone else has faced this issue. Also, using this method, we probably cannot use the APCC pointing/tracking model.

When I connect using The Skyx, the slew rate is good in one axis but not in the other. Moreover, the connection does lock up at times and I have to restart The SkyX. May be this is because the only connection option available with The SkyX is Paramount. I am guessing this can be made a generic interface but I guess that is a topic of discussion in a different forum.

What would be really nice to have is APCC providing a TCP server that Sky Safari can talk to. Is there a way to do this today? If not, is this something that can be considered? Not sure if one of the virtual com ports can be used somehow.

Regards
Hemant


Virus-free. www.avg.com



Re: 1600 GTO + AP portable pier vibration dampening?

Christopher Erickson
 

Always the best way to deal with unwanted vibrations in an observatory is to eliminate their generation, if possible.
 
How you do that will depend on what is generating those vibrations.
 
High frequency vibrations are usually easier to deal with then lower-frequency vibrations.
 
In my experience, anti-vibration pads and rubber mats usually don't do anything for low-frequency vibrations, such as what is likely generated by a rotating dome.
 
Soft start modules can help with jerky starts and can be found in both AC and DC models.  Most aren't designed for reversible motors so the addition of a couple of DPDT power relays and a diode are needed to integrate the soft start modules into your control system.  Most soft starts are able to provide a lot of starting torque to prevent startup stalling.
 
What can be done with your particular dome azimuth drive system will completely depend on how your particular system is designed and how it was built and installed.
 
Another option is to make sure that you never image while the dome is rotating.
 
If your dome control system supports it, it might be possible to move the dome past the scope point so the scope can track for the full duration of the present exposure without needing to move the dome.  Then only update the dome pointing between exposures.   
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 



From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 6:23 AM
To: ap-gto@...
Subject: Re: [ap-gto] 1600 GTO + AP portable pier vibration dampening?

Chris,
 
    I wonder if there is a motor  ”kick setting” on such dome control software, to overcome its static load. If that could be lessened, so that the drives ramp up rather than slam into motion, those small jogs may not be so disturbing.
 
Joe
 
From: 'Christopher Erickson' christopher.k.erickson@... [ap-gto]
Sent: Sunday, September 24, 2017 3:52 PM
To: ap-gto@...
Subject: RE: [ap-gto] 1600 GTO + AP portable pier vibration dampening?
 


Probably the best solution is to work on the dome azimuth rotation system to remove the rough movement and/or slow the dome down using a speed controller compatible with your azimuth motor.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 
 

Virus-free. www.avg.com


Re: PEMPro and accurate polar alignment

Roland Christen
 

Howard and I did some calculations of what the drift rate would be if you could accurately zero out the drift in RA at the zenith and zero the Dec drift at the celestial equator near the meridian. In a 1 hour circle around the zenith the stars will drift a maximum of 0.276 arc seconds. For a 2 hour circle (total of 4 hours from one side to the other) the maximum drift will be 0.594 arc seconds. Therefore one should be able to take reasonably long sub exposures (10 to 20 minutes) if the mount's periodic error is close to zero and you have a telescope that doesn't flex or wobble during that time.

With my setup of our 17" F8 Astro-Physics astrograph I have actually done that for 15 and 20 minute exposures and had 1 arc sec or less drift in each exposure. The 17" is light weight and sits on a 1600 encoder mount. Tracking is set to the exact sidereal rate.

Rolando



-----Original Message-----
From: chris1011@... [ap-gto]
To: ap-gto
Sent: Mon, Sep 25, 2017 2:13 pm
Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment



Here's what I do at the zenith. I link to the mount via MaximDL, acquire a guide star and start a guide exposure with aggressiveness set to zero. I open the tracking Error Graph and watch the RA drift. After a few minutes it is apparent that the drift is either + or -. In my case I know that with my camera orientation a minus drift means I need to raise the altitude axis, but in your case you need to make that determination by trial and error.

How much to lower or raise? Usually from a PEMPro drift method to the zenith adjustment the difference is about 1/4 rotation of the altitude adjustment wheel. In my case, after this adjustment I get less than 1 arc sec drift in a 15 minute time period on either side of the zenith up to about +-1 hour. Beyond those boundaries that, the drift begins to increase, but even though there is slightly more drift I can still do 5 to 10 minutes with no ovality showing up in the stars.

For those wishing to wade thru more rigorous methods of polar alignment and a handy calculator, here are two websites:
http://canburytech.net/DriftAlign/DriftAlign_3.html
http://www.bbastrodesigns.com/equatTrackingRatesCalc.html

Rolando



-----Original Message-----
From: Hemant Hariyani hemanthariyani@... [ap-gto] gto@...>
To: ap-gto gto@...>
Sent: Mon, Sep 25, 2017 12:54 pm
Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment



I tried measuring drift using PEMPro at zenith and am a bit surprised by the result.

I first tried to change position of altitude drift measurement in PEMPro slew dialogue but I was not able to select a degree offset less than 30. So I slewed my mount to zenith using my latitude as declination and a close to zero degree offset from meridian. I chose to be on the west of meridian.

I then started measurements in PEMPro to start with, it showed a huge offset and asked me to lower my altitude by 60 odd arc minutes. This reduced over a period of time and by the end of 5 minutes run, it was around 15 arc minutes. Without re-positioning the mount to zenith I let it continue for more time, restarting measurements and after about 20 minutes, this was down to 2.8 arc minutes. I tried this again and the results were fairly consistent. I have no idea on what is going on here. I did not affect this significant a change in measurements in such a short period of time. Any guesses on what can be going on? I have encoders enabled.

Regards
Hemant

 

On Mon, Sep 25, 2017 at 10:01 AM, chris1011@... [ap-gto] <ap-gto@...> wrote:
 

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?
Yes Ray, you are absolutely correct. The issue is whether you want zero drift around the zenith, which is useful for unguided imaging, or you want zero Dec drift (and variable RA drift) over larger parts of the sky. You can achieve one or the other. Pointing will be more accurate with the PEMPro drift alignment method, but you will get more RA drift overhead.

Rolando


-----Original Message-----
From: 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Sun, Sep 24, 2017 11:26 am
Subject: RE: [ap-gto] Re: PEMPro and accurate polar alignment

> Then what is the value of PEMPro, if it can't get this right?

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?

Best regards,

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Sunday, September 24, 2017 8:14 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment
>
>
>
> Then what is the value of PEMPro, if it can't get this right?
>
>



------------------------------------
Posted by: "Ray Gralak \(Groups\)" <groups3@...>
------------------------------------

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Re: Screws for Mach1 polar scope cover.

George
 

Tim,

 

The thread size is 8-32.

 

Regards,

 

George

 

George Whitney

Astro-Physics, Inc.

Phone:  815-282-1513

Email:  george@...

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, September 23, 2017 12:41 PM
To: ap-gto@...
Subject: [ap-gto] Screws for Mach1 polar scope cover.

 

 

Does anyone know the size and thread type for the screws that retain the sliding polar scope cover for a Mach1? I am going to make a bracket that uses these, so I need to get some longer thumb screws.



Many thanks



Tim


Re: APPM

dave@...
 

I meant i don’t think appm can blind solve.

Dave


Re: APPM

dave@...
 

It can also happen if not polar aligned close enough where your pointing is way off. I don’t think apcc can blind solve.

Dave


Re: PEMPro and accurate polar alignment

steven ho
 

Thank you very much!!


steve hoffman



From: ap-gto@... on behalf of chris1011@... [ap-gto]
Sent: Monday, September 25, 2017 3:13 PM
To: ap-gto@...
Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment
 
 

Here's what I do at the zenith. I link to the mount via MaximDL, acquire a guide star and start a guide exposure with aggressiveness set to zero. I open the tracking Error Graph and watch the RA drift. After a few minutes it is apparent that the drift is either + or -. In my case I know that with my camera orientation a minus drift means I need to raise the altitude axis, but in your case you need to make that determination by trial and error.

How much to lower or raise? Usually from a PEMPro drift method to the zenith adjustment the difference is about 1/4 rotation of the altitude adjustment wheel. In my case, after this adjustment I get less than 1 arc sec drift in a 15 minute time period on either side of the zenith up to about +-1 hour. Beyond those boundaries that, the drift begins to increase, but even though there is slightly more drift I can still do 5 to 10 minutes with no ovality showing up in the stars.

For those wishing to wade thru more rigorous methods of polar alignment and a handy calculator, here are two websites:
http://canburytech.net/DriftAlign/DriftAlign_3.html
http://www.bbastrodesigns.com/equatTrackingRatesCalc.html

Rolando




-----Original Message-----
From: Hemant Hariyani hemanthariyani@... [ap-gto]
To: ap-gto
Sent: Mon, Sep 25, 2017 12:54 pm
Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment



I tried measuring drift using PEMPro at zenith and am a bit surprised by the result.

I first tried to change position of altitude drift measurement in PEMPro slew dialogue but I was not able to select a degree offset less than 30. So I slewed my mount to zenith using my latitude as declination and a close to zero degree offset from meridian. I chose to be on the west of meridian.

I then started measurements in PEMPro to start with, it showed a huge offset and asked me to lower my altitude by 60 odd arc minutes. This reduced over a period of time and by the end of 5 minutes run, it was around 15 arc minutes. Without re-positioning the mount to zenith I let it continue for more time, restarting measurements and after about 20 minutes, this was down to 2.8 arc minutes. I tried this again and the results were fairly consistent. I have no idea on what is going on here. I did not affect this significant a change in measurements in such a short period of time. Any guesses on what can be going on? I have encoders enabled.

Regards
Hemant

 

On Mon, Sep 25, 2017 at 10:01 AM, chris1011@... [ap-gto] <ap-gto@...> wrote:
 

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?
Yes Ray, you are absolutely correct. The issue is whether you want zero drift around the zenith, which is useful for unguided imaging, or you want zero Dec drift (and variable RA drift) over larger parts of the sky. You can achieve one or the other. Pointing will be more accurate with the PEMPro drift alignment method, but you will get more RA drift overhead.

Rolando


-----Original Message-----
From: 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Sun, Sep 24, 2017 11:26 am
Subject: RE: [ap-gto] Re: PEMPro and accurate polar alignment

> Then what is the value of PEMPro, if it can't get this right?

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?

Best regards,

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Sunday, September 24, 2017 8:14 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment
>
>
>
> Then what is the value of PEMPro, if it can't get this right?
>
>



------------------------------------
Posted by: "Ray Gralak \(Groups\)" <groups3@...>
------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gto
------------------------------------

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Re: PEMPro and accurate polar alignment

Roland Christen
 

Here's what I do at the zenith. I link to the mount via MaximDL, acquire a guide star and start a guide exposure with aggressiveness set to zero. I open the tracking Error Graph and watch the RA drift. After a few minutes it is apparent that the drift is either + or -. In my case I know that with my camera orientation a minus drift means I need to raise the altitude axis, but in your case you need to make that determination by trial and error.

How much to lower or raise? Usually from a PEMPro drift method to the zenith adjustment the difference is about 1/4 rotation of the altitude adjustment wheel. In my case, after this adjustment I get less than 1 arc sec drift in a 15 minute time period on either side of the zenith up to about +-1 hour. Beyond those boundaries that, the drift begins to increase, but even though there is slightly more drift I can still do 5 to 10 minutes with no ovality showing up in the stars.

For those wishing to wade thru more rigorous methods of polar alignment and a handy calculator, here are two websites:
http://canburytech.net/DriftAlign/DriftAlign_3.html
http://www.bbastrodesigns.com/equatTrackingRatesCalc.html

Rolando



-----Original Message-----
From: Hemant Hariyani hemanthariyani@... [ap-gto]
To: ap-gto
Sent: Mon, Sep 25, 2017 12:54 pm
Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment



I tried measuring drift using PEMPro at zenith and am a bit surprised by the result.

I first tried to change position of altitude drift measurement in PEMPro slew dialogue but I was not able to select a degree offset less than 30. So I slewed my mount to zenith using my latitude as declination and a close to zero degree offset from meridian. I chose to be on the west of meridian.

I then started measurements in PEMPro to start with, it showed a huge offset and asked me to lower my altitude by 60 odd arc minutes. This reduced over a period of time and by the end of 5 minutes run, it was around 15 arc minutes. Without re-positioning the mount to zenith I let it continue for more time, restarting measurements and after about 20 minutes, this was down to 2.8 arc minutes. I tried this again and the results were fairly consistent. I have no idea on what is going on here. I did not affect this significant a change in measurements in such a short period of time. Any guesses on what can be going on? I have encoders enabled.

Regards
Hemant

 

On Mon, Sep 25, 2017 at 10:01 AM, chris1011@... [ap-gto] <ap-gto@...> wrote:
 

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?
Yes Ray, you are absolutely correct. The issue is whether you want zero drift around the zenith, which is useful for unguided imaging, or you want zero Dec drift (and variable RA drift) over larger parts of the sky. You can achieve one or the other. Pointing will be more accurate with the PEMPro drift alignment method, but you will get more RA drift overhead.

Rolando


-----Original Message-----
From: 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Sun, Sep 24, 2017 11:26 am
Subject: RE: [ap-gto] Re: PEMPro and accurate polar alignment

> Then what is the value of PEMPro, if it can't get this right?

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?

Best regards,

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Sunday, September 24, 2017 8:14 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment
>
>
>
> Then what is the value of PEMPro, if it can't get this right?
>
>



------------------------------------
Posted by: "Ray Gralak \(Groups\)" <groups3@...>
------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gto
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Re: 1600 GTO + AP portable pier vibration dampening?

Hemant Hariyani
 

Hello Everyone,

Thank you so much for your valuable feedback. I will try all these options out:
 - work on possibility of "smoothing" the motor out
 - Get pads for tripod - industrial or tripod pads. Thanks a lot for links!
 - rubber flooring and rubber pad under the observatory. 
 - sw control for isolating exposures from dome rotation

These are all great suggestions and I really appreciate all of your help. I will try these out and hopefully a combination of this will reduce the vibration.

Regards
Hemant



On Mon, Sep 25, 2017 at 11:22 AM, 'Joseph Zeglinski' J.Zeglinski@... [ap-gto] <ap-gto@...> wrote:
 

Chris,
 
    I wonder if there is a motor  ”kick setting” on such dome control software, to overcome its static load. If that could be lessened, so that the drives ramp up rather than slam into motion, those small jogs may not be so disturbing.
 
Joe
 
From: 'Christopher Erickson' christopher.k.erickson@gmail.com [ap-gto]
Sent: Sunday, September 24, 2017 3:52 PM
To: ap-gto@...
Subject: RE: [ap-gto] 1600 GTO + AP portable pier vibration dampening?
 


Probably the best solution is to work on the dome azimuth rotation system to remove the rough movement and/or slow the dome down using a speed controller compatible with your azimuth motor.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 
 



Re: PEMPro and accurate polar alignment

Hemant Hariyani
 

I tried measuring drift using PEMPro at zenith and am a bit surprised by the result.

I first tried to change position of altitude drift measurement in PEMPro slew dialogue but I was not able to select a degree offset less than 30. So I slewed my mount to zenith using my latitude as declination and a close to zero degree offset from meridian. I chose to be on the west of meridian.

I then started measurements in PEMPro to start with, it showed a huge offset and asked me to lower my altitude by 60 odd arc minutes. This reduced over a period of time and by the end of 5 minutes run, it was around 15 arc minutes. Without re-positioning the mount to zenith I let it continue for more time, restarting measurements and after about 20 minutes, this was down to 2.8 arc minutes. I tried this again and the results were fairly consistent. I have no idea on what is going on here. I did not affect this significant a change in measurements in such a short period of time. Any guesses on what can be going on? I have encoders enabled.

Regards
Hemant

 

On Mon, Sep 25, 2017 at 10:01 AM, chris1011@... [ap-gto] <ap-gto@...> wrote:
 


PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?
Yes Ray, you are absolutely correct. The issue is whether you want zero drift around the zenith, which is useful for unguided imaging, or you want zero Dec drift (and variable RA drift) over larger parts of the sky. You can achieve one or the other. Pointing will be more accurate with the PEMPro drift alignment method, but you will get more RA drift overhead.

Rolando


-----Original Message-----
From: 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Sun, Sep 24, 2017 11:26 am
Subject: RE: [ap-gto] Re: PEMPro and accurate polar alignment

> Then what is the value of PEMPro, if it can't get this right?

PEMPro tries to align to the non-refracted pole to minimize field rotation over the night.

Roland's technique of minimizing RA drift is great for short-term unguided tracking in a local area of the sky. The technique eliminates RA drift caused by polar alignment error, refraction, telescope component flexure, and worm wheel eccentricity, all of which can cause slight variations in RA speed.

But, I do not think polar alignment using RA is likely going to be as accurate as using the (non-moving) Declination axis unless there is an encoder on the RA axis to compensate for the worm wheel's (very slight) eccentricity, possible tooth-tooth variations in the worm wheel teeth, and residual periodic error.

Roland, please correct me if I am overlooking something here?

Best regards,

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Sunday, September 24, 2017 8:14 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] Re: PEMPro and accurate polar alignment
>
>
>
> Then what is the value of PEMPro, if it can't get this right?
>
>



------------------------------------
Posted by: "Ray Gralak \(Groups\)" <groups3@...>
------------------------------------

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Re: APCC + SkySafari?

Hemant Hariyani
 

Hello Christopher,

Thanks a lot for your response.

>As has been discussed in great detail recently, WiFi on the CP4 isn't currently a  fully-reliable connectivity option.  Of course WiFi is NEVER going to be a fully-reliable connectivity option for anything.  That's just the nature of WiFi anyway.
 
>If you want 99.999% reliable communications with your mount, use RS-232 or Ethernet connectivity.  Don't use WiFi or USB.

I completely agree and understand the limitation of wifi connection. I use RS-232 between my PC and my mount. I believe the problem with wireless connection in this case is that I am not able to re-connect to the mount. The mount wifi is up (I can open it in my browser) and so is my phone's. Restarting phone does not help, restarting mount does. This tells me that GTO CP4 is somehow left in a state that does not allow this connection anymore. Serial connection to the mount continues to work fine when this happens. If there is a way to collect logs, I will be more than happy to provide it if that helps.

My main point however was more in terms of being able to use APCC Pro as the point of interface between SkySafari or any other mobile software/hand control and the mount. Seems like this should be possible. I was wondering if anyone had tried it or have any suggestions.

Regards
Hemant




On Sun, Sep 24, 2017 at 2:50 PM, 'Christopher Erickson' christopher.k.erickson@... [ap-gto] <ap-gto@...> wrote:
 

As has been discussed in great detail recently, WiFi on the CP4 isn't currently a  fully-reliable connectivity option.  Of course WiFi is NEVER going to be a fully-reliable connectivity option for anything.  That's just the nature of WiFi anyway.
 
If you want 99.999% reliable communications with your mount, use RS-232 or Ethernet connectivity.  Don't use WiFi or USB.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, September 24, 2017 7:27 AM
To: ap-gto@...
Subject: [ap-gto] APCC + SkySafari?

Hello all,

I use Sky Safari to control my GTO mount. I have tried two ways of connecting Sky Safari to GTO:

1. Using GTO's IP address (port 23) and setting mount type to Astro-Physics GTO

2. Using The Skyx (My PC's IP address and The Skyx server port) and setting the mount to Paramount+TheSkyx

When I connect directly to GTO, the connection works most of the time but disconnects occasionally and the only solution then is to power cycle the mount. Not sure if anyone else has faced this issue. Also, using this method, we probably cannot use the APCC pointing/tracking model.

When I connect using The Skyx, the slew rate is good in one axis but not in the other. Moreover, the connection does lock up at times and I have to restart The SkyX. May be this is because the only connection option available with The SkyX is Paramount. I am guessing this can be made a generic interface but I guess that is a topic of discussion in a different forum.

What would be really nice to have is APCC providing a TCP server that Sky Safari can talk to. Is there a way to do this today? If not, is this something that can be considered? Not sure if one of the virtual com ports can be used somehow.

Regards
Hemant


Virus-free. www.avg.com



Re: APPM

cford81@...
 

When you say the camera took some exposures but had more failed attempts you were getting at least some plate solves?

Usually when I get failed attempts it is because my telescope is pointing into a tree. Do you have the horizon limits properly specified to the mount is always trying to solve against clear sky?

Chris



From: "samara_c@... [ap-gto]"
To: ap-gto@...
Sent: Monday, September 25, 2017 10:15:27 AM
Subject: [ap-gto] APPM

 

Good afternoon everyone,


Last week for the first time I tried to build a pointing model with APPM and I failed miserably. I searched on the groups but couldn't find anything. Does anyone know of and/or could point me to some instructions other than the AP manual? I read that but I must be doing something wrong, the mount pointed, the camera took some exposures but I had more failed attempts than successful ones so a Dummy step-by-step would be really appreciated.


Thanks!





Re: APPM

Howard Hedlund
 

Hi Samara,

 

Give me a call or Skype at AP.  I may be able to help.  It might also help me improve the instructions in the Help file if I can determine what was unclear to you.  Be forewarned though, It may need to wait until after AIC if you can delay that long.

 

Mag. 7 Skies!

 

Howard Hedlund

Astro-Physics, Inc.

Phone: 815-282-1513

www.astro-physics.com

Please include this e-mail with your response.

 

P Consider the environment before printing this e-mail.

 

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 5:15 PM
To: ap-gto@...
Subject: [ap-gto] APPM

 

 

Good afternoon everyone,

Last week for the first time I tried to build a pointing model with APPM and I failed miserably. I searched on the groups but couldn't find anything. Does anyone know of and/or could point me to some instructions other than the AP manual? I read that but I must be doing something wrong, the mount pointed, the camera took some exposures but I had more failed attempts than successful ones so a Dummy step-by-step would be really appreciated.

Thanks!

 


Re: PEM Files Upoloaded: Need sanity check

W Hilmo
 

My software automatically compensates for the declination of the actual target when it determines the duration of the guide pulses, so I don’t need to recalibrate the guider for the specific area of the sky where I am imaging.

 

I just calibrate near the celestial equator because that’s where a given movement in right ascension results in the largest effective movement of the camera.  In other words, if I have my X and Y calibration times equal (the amount of time that the mount moves during calibration), then both lines in the “L” are the same length.  If I were to calibrate at a higher declination, then the Y line would be shorter than the X line (note that I am talking about mount axes, not camera field axes).  If I tried to calibrate near the pole, then the Y line in the “L” would be too short for an effective calibration.  If you’ve ever seen the MaxIm/DL error “mount moved less than 5 pixels in Y”, that is one of the possible causes.

 

This made a significant difference when I was imaging with a Celestron CGE.  My AP1600 tracks so well, that I am basically guiding out mirror shift and flex in the scope.  As long as my calibration doesn’t result in over-aggressive guide pulses, the results are always good no matter where I calibrate, within reason with respect to the pole.  If the guide pulses are too aggressive, then the result is oscillation between guide exposures.  It’s pretty easy to recognize and can be temporarily addresses by reducing the aggressiveness setting in the guide software.

 

-Wade

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 9:50 AM
To: ap-gto@...
Subject: Re: [ap-gto] Re: PEM Files Upoloaded: Need sanity check

 

 

Wade,

 

    After you calibrate your guider at the Celestial Equator, do you also recalibrate again each time – near the target you will be imaging, to maximize guider accuracy?

 

    Or, is a single CE calibration sufficient, so long as the DEC value is “changed” when you are actually guiding at the target DEC ?

 

    Otherwise, I wonder if CE position for calibration can be worsened, if DEC=0 is not set in the guider software initially, and changed to actual target DEC when guiding is started (even without re-calibrating “at the target location”).

For that matter, does Calibration even  look at the user entered DEC value – or just when finally starting the guiding?

 

Joe


Re: GTO1100 CP4 Telescope position

Howard Hedlund
 

Hi Thomas,

 

With regard to the time zone, Your time actual zone is NOT 2 East.  It is 1 East with a daylight savings adjustment to make it 2 East.  In the keypad, select Time Zone 01 (It will get the East from your longitude) and set the DST to Summer (for the time being).  In APCC, set the Time Zone to:   (UTC+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm.    This will result in all your devices having a net time offset of UTC + 2.

 

You can also set everything to UTC and forget about DST and time zones.  However, for this to work without problems, EVERYTHING must be set to UTC including your PC.   

 

To find the log files, use the Log Zipper Utility.  That way the settings files are also included.   Otherwise, they are normally at:  C:\ProgramData\Astro-Physics\APCC\Logs\    and at:   C:\ProgramData\Astro-Physics\ASCOM\Logs\

 

I too am attending AIC, but I may be able to give them a look.  E-mail them to    howard at astro-physics dot com

 

Mag. 7 Skies!

 

Howard Hedlund

Astro-Physics, Inc.

Phone: 815-282-1513

www.astro-physics.com

Please include this e-mail with your response.

 

P Consider the environment before printing this e-mail.

 

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, September 25, 2017 4:50 PM
To: ap-gto@...
Subject: Re: [ap-gto] GTO1100 CP4 Telescope position

 

 

Thanks I will send you the log file.

 

Could you advise me regarding the folder path of the logfile?

KR

Thomas


Am 25.09.2017 um 18:43 schrieb 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...>:

 

Hi Thomas,

It depends on how the mount was initialized, and what initialized it. I invite you look at your apcc log files to see how time zone and longitude/latitude were initialized, and maybe you'll find something is configured incorrectly. As I said, you should probably check all your software settings, including those on apcc.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma

> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Monday, September 25, 2017 8:01 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] GTO1100 CP4 Telescope position
>
>
>
> Ok, I will try your suggested procedure.
>
> But I need your help for these 2 points:
>
> - as you can see at the screenshot below, there is a difference between the value of the mount location in
> longitude (-06:09:00) and the longitude value of the site information (-06:09:54). The value of the mount
> location is wrong. Pushing the Refresh button makes no change.
>
> - pleas explain why the time offset value is set to
> -3:00:00? We are here at UTC -2 and Daylight saving time is on. Without DST (in Winter) we do have UTC -
> 1
>
> https://www.dropbox.com/s/pq0z6hi1dh22htf/Screenshot%202017-09-21%2023.15.16.png?dl=0
>
>
> Kind regards
>
> Thomas
>
> Am 25.09.2017 um 16:11 schrieb 'Ray Gralak (Groups)' group s3@...
> <mailto:groups3@...> [ap-gto] <ap-gto@...>:
>
>
>
>
>
> Hi Thomas,
>
> If you are still having a problem with the 3D View you probably should do mount/setup "sanity check".
> By that, I mean you should make sure that time/time zone, latitude/longitude are set to the same values
> across all software and that computer time matches the mount time.
>
> You then should then, unpark and slew to about 0 Dec near the meridian and do a plate solve+recal
> and then park to Park 3. If the scope goes to the proper Park 3 position then the 3D View should be all set to
> use, provided latitude/longitude are set correctly in all software.
>
> Best regards,
>
> -Ray Gralak
> Author of APCC (Astro-Physics Command Center): http://www.astro-
> physics.com/index.htm?products/accessories/software/apcc/apcc
> Author of PEMPro: http://www.ccdware.com
> Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
> Author of PulseGuide: http://www.pulseguide.com
> Author of Sigma: http://www.gralak.com/sigma
>
> > -----Original Message-----
> > From: ap-gto@... [mailto:ap-gto@...]
> > Sent: Monday, September 25, 2017 6:49 AM
> > To: ap-gto@...
> > Subject: Re: [ap-gto] GTO1100 CP4 Telescope position
> >
> >
> >
> > May be this the problem?
> >
> > https://www.dropbox.com/s/pq0z6hi1dh22htf/Screenshot%202017-09-21%2023.15.16.png?dl=0
> >
> > Mount Location
> > - Time Offset -3:00:00
> >
> > We have here at 51:37:24 N and 06:09:54 O UTC -2:00:00 and DST on
> >
> > The difference of the position in RA - when you compare 3D viewer Window and the position in fact
> - looks
> > around 45 deg./3 hours in RA axis.
> >
> > Regards
> >
> > Thomas
> >
> > Am 25.09.2017 um 15:28 schrieb 'T. Hellwing' t.hellwing@... [ap-gto] <ap-
> gto@...>:
> >
> >
> >
> >
> >
> >
> >
> > Hi Joe,
> >
> > no limits set.
> >
> > Regards
> >
> > Thomas
> >
> > Am 25.09.2017 um 15:21 schrieb 'Joseph Zeglinski' J.Zeglinski@... [ap-gto] <ap-
> > gto@...>:
> >
> >
> >
> >
> >
> >
> >
> > By chance have you set APCC LIMITS, so that the option is set to Park the mount at some
> > Home coordinates or standard Park, when one is reached?
> >
> > Joe
> >
> >
> >
> >
> >
> >
> >
>
>
>
>


APPM

Samara Nagle
 

Good afternoon everyone,

Last week for the first time I tried to build a pointing model with APPM and I failed miserably. I searched on the groups but couldn't find anything. Does anyone know of and/or could point me to some instructions other than the AP manual? I read that but I must be doing something wrong, the mount pointed, the camera took some exposures but I had more failed attempts than successful ones so a Dummy step-by-step would be really appreciated.

Thanks!