Date   

Re: New file uploaded to ap-gto

Roland Christen
 

Hello Astronuts,

I posted tracking curve for our 1100 encoder mount for those who are technically interested in seeing how accurate it tracks. Also in the image is a test made with a high resolution (also expensive) commercial encoder that uses a relative encoder scheme. The difference is in the way interpolation is done in Absolute encoders versus Relative encoders.

Some people think there is no difference between the two, that the only difference is the need for a homing sensor in the relative encoder. That has never been the problem, what is the problem is the interpolation error that is inherent in relative encoders. The Renishaw Absolute encoder has undetectable interpolation error.

Rolando



-----Original Message-----
From: ap-gto
To: ap-gto
Sent: Mon, Apr 1, 2019 4:32 pm
Subject: [ap-gto] New file uploaded to ap-gto

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the ap-gto
group.

  File        : /Renishaw Encoder tracking tests/TrackingComparison4.jpg
  Uploaded by : uncarollo2 <chris1011@...>
  Description : Comparing Renishaw Absolute Encoder tracking with Relative encoder.

You can access this file at the URL:

To learn more about file sharing for your group, please visit:

Regards,

uncarollo2 <chris1011@...>


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New file uploaded to ap-gto

ap-gto@...
 

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the ap-gto
group.

File : /Renishaw Encoder tracking tests/TrackingComparison4.jpg
Uploaded by : uncarollo2 <chris1011@aol.com>
Description : Comparing Renishaw Absolute Encoder tracking with Relative encoder.

You can access this file at the URL:
https://groups.yahoo.com/neo/groups/ap-gto/files/Renishaw%20Encoder%20tracking%20tests/TrackingComparison4.jpg

To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398

Regards,

uncarollo2 <chris1011@aol.com>


Re: New Website - Notification Lists?

John Pepper
 

I unfortunately did not sign up on the list. Does that mean that after the list is done no more scopes will be produced?


Re: New Website - Notification Lists?

 

Thanks! It is so much easier to get around isn’t it?

 

If you look under Order Info in the menu bar, you will see a Notification tab. It explains that we still have all of the lists and will use them when we open a new production run, for instance the upcoming 92mm run. No worries. If you signed up on a list, you are still on that list.

 

Clear Skies,

 

Marj Christen

Astro-Physics, Inc

11250 Forest Hills Rd

Machesney Park, IL 61115

Phone: 815-282-1513

Fax: 815-282-9847

www.astro-physics.com

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Monday, April 01, 2019 1:09 AM
To: ap-gto@...
Subject: [ap-gto] New Website - Notification Lists?

 

 

Love the new website!  One thing that isn't particularly clear is how the notification list process will work going forward.  It appears that these lists will no longer exists but you will still make telescopes and mounts.  If someone wants an RH305, for example, do you now need to wait until some are in stock and purchase on a first-come first-serve basis?


New Website - Notification Lists?

John Pepper
 

Love the new website!  One thing that isn't particularly clear is how the notification list process will work going forward.  It appears that these lists will no longer exists but you will still make telescopes and mounts.  If someone wants an RH305, for example, do you now need to wait until some are in stock and purchase on a first-come first-serve basis?


Re: APCC Meridian Limits Videos On New Site

Ray Gralak
 

There are a few more recent videos on my Sirius Imaging channel:

https://www.youtube.com/channel/UCWGqhOYCVEa6D9iqYpqyYag

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

-----Original Message-----
From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Sunday, March 31, 2019 3:16 PM
To: ap-gto@yahoogroups.com
Subject: [ap-gto] Re: APCC Meridian Limits Videos On New Site



These are Ray Gralak's videos available from the old web site. None seem to pertain to meridian limits. That must
be elsewhere.

https://www.screencast.com/users/rgralak/views/Videos



Bryan


Re: APCC Meridian Limits Videos On New Site

Worsel
 

These are Ray Gralak's videos available from the old web site.  None seem to pertain to meridian limits.  That must be elsewhere.



Bryan


Re: APCC Meridian Limits Videos On New Site

 

I don’t think that it was ever linked from the old site. I have asked Ray which videos are available and we will link to them from Technical Support.

 

Clear Skies,

 

Marj Christen

Astro-Physics, Inc

11250 Forest Hills Rd

Machesney Park, IL 61115

Phone: 815-282-1513

Fax: 815-282-9847

www.astro-physics.com

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, March 31, 2019 10:41 AM
To: ap-gto@...
Subject: [ap-gto] APCC Meridian Limits Videos On New Site

 

 

Anyone know where to find these on the new site?


APCC Meridian Limits Videos On New Site

dvuolhhr6nx4a532a3phnju3zs6lzvlgxdl2wzaf@...
 

Anyone know where to find these on the new site?


Re: FujiFilm XT3 adapter

Stuart Heggie <stuart.j.heggie@...>
 

Well, you'll need some kind of adapter anyway and it is likely that a commercial adapter that allows Nikkor lenses as well as connecting to the telescope will be a) cheaper and b) have utility beyond astronomy. Seems worth considering since you said this was your daytime camera not a camera bought and modified to only be an astro camera.


On Sun, 31 Mar 2019 at 10:18, 'Mike Shade' mshade@q.com [ap-gto] <ap-gto@...> wrote:
 

Thanks...I was contemplating this but thought I would check and see if someone else had done what I am proposing and how they did it...I know there can be some spacing concerns with the FF. It is setup properly for the Nikon...Yes it is a mirrorless camera, the Fuji.

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

International Dark Sky Association: <http://www.darksky.org/> www.darksky.org

From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, March 31, 2019 7:12 AM
To: ap-gto@...
Subject: Re: [ap-gto] FujiFilm XT3 adapter

Mike, I have not done this but it seems to me there should be an adapter to use Nikkor lenses on the Fuji camera. If there is, you can put that on the camera body then it would attach just like your Nikon camera did. Possibly with no change in spacers. Is the Fuji camera mirrorless? If so you probably have the back-focus for the adapter to fit without spacers.

Stuart Heggie

http://www.stuartheggie.com/featured.html <http://www.stuartheggie.com>

On Sun, 31 Mar 2019 at 10:04, 'Mike Shade' mshade@q.com [ap-gto] <ap-gto@...> wrote:

Have completely changed terrestrial cameras from Nikon to FujiFilm XT3. Curious if there is a reasonably easy way to attach this camera to my AP filed flattener for use in my 130...I have everything plumbed for Nikon, of course but see nothing for Fuji X-mounts...anyone done similar?

Thanks.

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

International Dark Sky Association: www.darksky.org <http://www.darksky.org/>

[Non-text portions of this message have been removed]


Re: FujiFilm XT3 adapter

Mike Shade
 

Thanks...I was contemplating this but thought I would check and see if someone else had done what I am proposing and how they did it...I know there can be some spacing concerns with the FF. It is setup properly for the Nikon...Yes it is a mirrorless camera, the Fuji.



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: <http://www.darksky.org/> www.darksky.org



From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Sunday, March 31, 2019 7:12 AM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] FujiFilm XT3 adapter





Mike, I have not done this but it seems to me there should be an adapter to use Nikkor lenses on the Fuji camera. If there is, you can put that on the camera body then it would attach just like your Nikon camera did. Possibly with no change in spacers. Is the Fuji camera mirrorless? If so you probably have the back-focus for the adapter to fit without spacers.




Stuart Heggie

http://www.stuartheggie.com/featured.html <http://www.stuartheggie.com>





On Sun, 31 Mar 2019 at 10:04, 'Mike Shade' mshade@q.com [ap-gto] <ap-gto@yahoogroups.com> wrote:



Have completely changed terrestrial cameras from Nikon to FujiFilm XT3. Curious if there is a reasonably easy way to attach this camera to my AP filed flattener for use in my 130...I have everything plumbed for Nikon, of course but see nothing for Fuji X-mounts...anyone done similar?



Thanks.



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: www.darksky.org <http://www.darksky.org/>


Re: FujiFilm XT3 adapter

Stuart Heggie <stuart.j.heggie@...>
 

Mike, I have not done this but it seems to me there should be an adapter to use Nikkor lenses on the Fuji camera. If there is, you can put that on the camera body then it would attach just like your Nikon camera did. Possibly with no change in spacers. Is the Fuji camera mirrorless? If so you probably have the back-focus for the adapter to fit without spacers.


On Sun, 31 Mar 2019 at 10:04, 'Mike Shade' mshade@q.com [ap-gto] <ap-gto@...> wrote:
 

Have completely changed terrestrial cameras from Nikon to FujiFilm XT3.  Curious if there is a reasonably easy way to attach this camera to my AP filed flattener for use in my 130...I have everything plumbed for Nikon, of course but see nothing for Fuji X-mounts...anyone done similar?

 

Thanks.

 

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 


FujiFilm XT3 adapter

Mike Shade
 

Have completely changed terrestrial cameras from Nikon to FujiFilm XT3.  Curious if there is a reasonably easy way to attach this camera to my AP filed flattener for use in my 130...I have everything plumbed for Nikon, of course but see nothing for Fuji X-mounts...anyone done similar?

 

Thanks.

 

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 


Re: Worm mesh and PEC

Joe Zeglinski
 

Pawel,
 
    Don’t forget to SAVE the current PEC curve data first. before doing a fresh one.
You never know if your initial one, which can be restored,  was better to begin with. Would be nice if PemPro popped up a reminder to do so, or it would just save it automatically, as a backup, even for comparison tests.
 
Joe Z.
 


Re: Worm mesh and PEC

Pawel Lancucki
 

Hi Guys

Thank you for feedback. I think I will re-run PEC anyway after the worm mesh adjustment, now on the next full moon ;-)

CS

Pawel Lancucki



Re: APCC Pro 1.7.1.1 Orphaned Process

Danny Flippo
 

Ray, I found the issue.  My driver wasn't terminating a thread properly.  Sorry for the false alarm.

-Dan


Re: SDE in encoder mounts

Roland Christen
 

That's excellent. Similar to what i get with my 1600 AE with the 17" Astrograph in typical Midwest seeing. There have been nights that were very steady with resulting RMS guiding below 0.1 arc sec. for several hours. Normally though i get more like 0.25 - 0.3 most nights.

On our remote setup down in Chile at the Las Campanas site, our 12" astrograph mounted on a 1600 AE gets routinely 0.1 RMS guiding. Seeing down there is almost always below 0.5 arc sec.

Rolando



-----Original Message-----
From: steven hoffman stevenhoffman53@... [ap-gto]
To: ap-gto@...
Sent: Sat, Mar 30, 2019 6:54 pm
Subject: Re: [ap-gto] SDE in encoder mounts



So glad to have 1600GTO-AE. Here is 5 hours of PHD2 guiding from last week. Notice the points plotted in the lower right hand "bullseye".

This time with the image file to the PHD2 screen shot.
/
groups.yahoo.com



From: ap-gto@... on behalf of chris1011@... [ap-gto]
Sent: Saturday, March 30, 2019 7:01 PM
To: ap-gto@...
Subject: [ap-gto] SDE in encoder mounts
 
 
Hi Astronuts,

There is an ongoing discussion in Cloudy Nights about rapid oscillations in the RA tracking rate of encoder mounts. Yes it's real and all encoder mounts that use relative encoders have it. It's caused by sub-divisional error and is typically about 5% or more of the fundamental line spacing. The highest resolution relative encoders have on the order of 50 - 100 arc seconds spacing between lines. These are then interpolated electronically to provide finer line counts down to the sub-arc sec level - however with a typical error of 2.5 - 5 arc seconds. This results in a fast ripple motion in the RA tracking rate that cannot be guided out.

Encoders that have 50 arc sec spacing will exhibit a back and forth motion in the RA tracking every 3.3 seconds. This averages out of course over a period of time so one can spec it as an average or RMS level close to zero. These motions may not record using short and medium focal length scopes, but can easily be seen with long focus SCTs and astrographs. In fact there are videos showing a star bobbling back and forth in RA in a C11 with a video camera attached. Of course if your scope/camera combo is operating at 4 arc sec per pixel, a 3 arc sec star motion will never be detected since the light of any one star will never leave the pixel.

The good news for Astro-Physics customers is that we have always used Renishaw Resolute Absolute encoders, which use a different method for achieving high resolution. We chose Renishaw precisely because they have no detectable SDE. The encoder ring accuracies are certified by Renishaw using laboratory standards. The encoder readheads use a very unique and accurate method to determine any one of 67 million (2^26) individual positions around the 360 degree encoder ring. The readheads have 20 times lower sub-divisional error than any relative encoder system. Yes, they are much more expensive than relative encoders, but they produce the accuracy needed for real precise tracking in an astronomical mount.

Roland Christen



Re: SDE in encoder mounts

steven ho
 

So glad to have 1600GTO-AE. Here is 5 hours of PHD2 guiding from last week. Notice the points plotted in the lower right hand "bullseye".

This time with the image file to the PHD2 screen shot.
/
groups.yahoo.com



From: ap-gto@... on behalf of chris1011@... [ap-gto]
Sent: Saturday, March 30, 2019 7:01 PM
To: ap-gto@...
Subject: [ap-gto] SDE in encoder mounts
 
 

Hi Astronuts,

There is an ongoing discussion in Cloudy Nights about rapid oscillations in the RA tracking rate of encoder mounts. Yes it's real and all encoder mounts that use relative encoders have it. It's caused by sub-divisional error and is typically about 5% or more of the fundamental line spacing. The highest resolution relative encoders have on the order of 50 - 100 arc seconds spacing between lines. These are then interpolated electronically to provide finer line counts down to the sub-arc sec level - however with a typical error of 2.5 - 5 arc seconds. This results in a fast ripple motion in the RA tracking rate that cannot be guided out.

Encoders that have 50 arc sec spacing will exhibit a back and forth motion in the RA tracking every 3.3 seconds. This averages out of course over a period of time so one can spec it as an average or RMS level close to zero. These motions may not record using short and medium focal length scopes, but can easily be seen with long focus SCTs and astrographs. In fact there are videos showing a star bobbling back and forth in RA in a C11 with a video camera attached. Of course if your scope/camera combo is operating at 4 arc sec per pixel, a 3 arc sec star motion will never be detected since the light of any one star will never leave the pixel.

The good news for Astro-Physics customers is that we have always used Renishaw Resolute Absolute encoders, which use a different method for achieving high resolution. We chose Renishaw precisely because they have no detectable SDE. The encoder ring accuracies are certified by Renishaw using laboratory standards. The encoder readheads use a very unique and accurate method to determine any one of 67 million (2^26) individual positions around the 360 degree encoder ring. The readheads have 20 times lower sub-divisional error than any relative encoder system. Yes, they are much more expensive than relative encoders, but they produce the accuracy needed for real precise tracking in an astronomical mount.

Roland Christen


New file uploaded to ap-gto

ap-gto@...
 

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the ap-gto
group.

File : /phd2_4.PNG
Uploaded by : sink45ny <stevenhoffman53@hotmail.com>
Description : 5 hours of guiding with 1600GTO-AE

You can access this file at the URL:
https://groups.yahoo.com/neo/groups/ap-gto/files/phd2_4.PNG

To learn more about file sharing for your group, please visit:
https://help.yahoo.com/kb/index?page=content&y=PROD_GRPS&locale=en_US&id=SLN15398

Regards,

sink45ny <stevenhoffman53@hotmail.com>


Re: SDE in encoder mounts

steven ho
 

So glad to have 1600GTO-AE. Here is 5 hours of PHD2 guiding from last week. Notice the points plotted in the lower right hand "bullseye".

[cid:fe980320-70c8-47b3-9787-626b73aa60be]

________________________________
From: ap-gto@yahoogroups.com <ap-gto@yahoogroups.com> on behalf of chris1011@aol.com [ap-gto] <ap-gto@yahoogroups.com>
Sent: Saturday, March 30, 2019 7:01 PM
To: ap-gto@yahoogroups.com
Subject: [ap-gto] SDE in encoder mounts



Hi Astronuts,

There is an ongoing discussion in Cloudy Nights about rapid oscillations in the RA tracking rate of encoder mounts. Yes it's real and all encoder mounts that use relative encoders have it. It's caused by sub-divisional error and is typically about 5% or more of the fundamental line spacing. The highest resolution relative encoders have on the order of 50 - 100 arc seconds spacing between lines. These are then interpolated electronically to provide finer line counts down to the sub-arc sec level - however with a typical error of 2.5 - 5 arc seconds. This results in a fast ripple motion in the RA tracking rate that cannot be guided out.

Encoders that have 50 arc sec spacing will exhibit a back and forth motion in the RA tracking every 3.3 seconds. This averages out of course over a period of time so one can spec it as an average or RMS level close to zero. These motions may not record using short and medium focal length scopes, but can easily be seen with long focus SCTs and astrographs. In fact there are videos showing a star bobbling back and forth in RA in a C11 with a video camera attached. Of course if your scope/camera combo is operating at 4 arc sec per pixel, a 3 arc sec star motion will never be detected since the light of any one star will never leave the pixel.

The good news for Astro-Physics customers is that we have always used Renishaw Resolute Absolute encoders, which use a different method for achieving high resolution. We chose Renishaw precisely because they have no detectable SDE. The encoder ring accuracies are certified by Renishaw using laboratory standards. The encoder readheads use a very unique and accurate method to determine any one of 67 million (2^26) individual positions around the 360 degree encoder ring. The readheads have 20 times lower sub-divisional error than any relative encoder system. Yes, they are much more expensive than relative encoders, but they produce the accuracy needed for real precise tracking in an astronomical mount.

Roland Christen

18561 - 18580 of 83217