Date   

Re: Tracking issues with AP900

Chanan Greenberg
 

Hi Rolando,

I doubt this is a drift issue. 1) I did Drift alignment and got to 7 minutes of no drift when pointing to a star at the cross section of the meridian and the celestial equator and no drift when pointing to a star in the east. 2) I measured my polar alignment using PoleAlignMax and it showed I was within 7 arc-minutes off the refracted pole which may not be perfect but I have done a lot of imaging with worse alignment.

This is unlikely the reason that I can get 1-2 minutes of perfectly round stars pointing in one direction and get elongated stars and significant drifting when pointing in the other direction. 

Thanks
Chanan


Re: Tracking issues with AP900

Roland Christen
 


A friend suggested this could be mirror flop on the C-9.25 (it is quite old). Before I take that down and try a different scope - any other ideas about what could be throwing off my tracking?
That always suggest that polar alignment is off. Check drift near the meridian pointing south. You may find that the Dec axis is drifting, which means that the azimuth alignment is off. Of course when you point below about 45 degrees altitude you will have large amounts of RA drift caused by atmospheric refraction. I'm assuming that you know this and are accounting for that. here is a tracking calculator that tells you how much drift to expect: http://www.bbastrodesigns.com/equatTrackingRatesCalc.html

Rolando


-----Original Message-----
From: Chanan Greenberg <chanan2009@...>
To: main@ap-gto.groups.io
Sent: Fri, Aug 7, 2020 11:51 am
Subject: [ap-gto] Tracking issues with AP900

Hi All,

I am using an old AP900 GTOCP1. This is a mount belonging to a friend of mine which I used extensively 10 years ago, I was able to do 15 minute unguided exposures with this mount. 
It currently has a C-9.25 and an 80mm APO piggyback. My polar alignment is decent (7 arc-minutes off the refracted pole). I have triple checked the balance and it is balanced in all axis. 

Pointing anywhere North, North East or North West I get nice round stars going unguided for 60-90 seconds, with auto-guiding I still get nice round stars with 5 to 10 minute exposures.
Pointing south - unguided I cannot go longer than 30 seconds before I start seeing drift and even with auto-guiding on I see the stars getting elongated within 60 seconds.

A friend suggested this could be mirror flop on the C-9.25 (it is quite old). Before I take that down and try a different scope - any other ideas about what could be throwing off my tracking?
Thanks
Chanan


Re: Tracking issues with AP900

Chanan Greenberg
 

Hi Mike,
Thanks for all the input.
I noted that basic tracking was worse when pointing south (and later when testing autoguiding - that too was worse when pointing south).
So even with no auto-guiding there is a noticeable difference in the quality of tracking. 

Guess I will take down the C-9.25 and try one of my newtonians to take mirror flop out of the equation. 

Will also read the flexure material

Thanks!
Chanan


Re: Tracking issues with AP900

Mike Dodd
 

On 8/7/2020 12:51 PM, Chanan Greenberg wrote:
It currently has a C-9.25 and an 80mm APO piggyback.
...even with auto-guiding on I see the stars getting
elongated within 60 seconds.

A friend suggested this could be mirror flop on the C-9.25 (it is quite
old). Before I take that down and try a different scope - any other
ideas about what could be throwing off my tracking?
Are you talking about TRACKING or GUIDING? You said you can get good unguided exposures pointing northward, but not southward while autoguiding.

Autoguiding corrects tracking errors, so that indicates to me that something in the optical train is causing the problem.

How are you autoguiding? Internal guide sensor? off-axis guider? Separate guide scope/camera?

If you're using a separate guider, my A-number-one suspect is differential flexure. I struggled with this, but finally solved it with a number of fixes, which you can read about here: <http://astronomy.mdodd.com/flexure.html>

If autoguiding can be ruled out, my next suspect is mirror flop. I had a C9.25, and greatly reduced mirror flop by disassembling the OTA and adding three thin brass strips along the central tube to act as shims for the mirror. I don't have any photos, but essentially I removed the corrector lens, pulled out the mirror, and cleaned grease off the central tube.

Then I cut three strips from (probably) 0.010" or 0.015" brass sheet. I looped the ends over the open end of the tube, and secured them with Goop viscous adhesive. I don't remember how I secured the bottom ends (probably with Goop). I did NOT apply Goop along the strips where the mirror slides.

Bottom line: The shims greatly reduced mirror flop.

I also machined a locking focuser knob <http://machinist.mdodd.com/project-focuser-knob.html> that reduce mirror movement even more. (I had an external motorized focuser, so I could lock the mirror in place close to focus, then achieve fine focus with the external focuser.)

This is long an involved, but I hope the information is helpful.

--- Mike
http://astronomy.mdodd.com


Tracking issues with AP900

Chanan Greenberg
 

Hi All,

I am using an old AP900 GTOCP1. This is a mount belonging to a friend of mine which I used extensively 10 years ago, I was able to do 15 minute unguided exposures with this mount. 
It currently has a C-9.25 and an 80mm APO piggyback. My polar alignment is decent (7 arc-minutes off the refracted pole). I have triple checked the balance and it is balanced in all axis. 

Pointing anywhere North, North East or North West I get nice round stars going unguided for 60-90 seconds, with auto-guiding I still get nice round stars with 5 to 10 minute exposures.
Pointing south - unguided I cannot go longer than 30 seconds before I start seeing drift and even with auto-guiding on I see the stars getting elongated within 60 seconds.

A friend suggested this could be mirror flop on the C-9.25 (it is quite old). Before I take that down and try a different scope - any other ideas about what could be throwing off my tracking?
Thanks
Chanan


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Leo Shatz
 

Slewing works in all directions - both from SGP and APCC controls.


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Steve Reilly
 

Just out of curiosity can you move the scope in all 4 directions N/S/E/W with APCC or other software means?

 

-Steve

 

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Leo Shatz
Sent: Friday, August 7, 2020 11:48 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Pier flip before meridian crossing is not possible with SGP and Mach1

 

Ray, thanks for the link. I haven't yet looked at it yet (but will do shortly) - since I'm having now more serious issue : SGP suddenly cannot do any kind of flips (including in position after meridian crossing), i.e. neither auto nor manual flip works anymore. This is the typical output in SGP log file. I've tried to reboot my PC, tried different APCC/SGP versions, it just doesn't work.

[08/07/20 18:36:34.542][DEBUG][Sequence Thread][SQ;] Telescope is on the West side of the mount

[08/07/20 18:36:34.543][DEBUG][Sequence Thread][SQ;] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: 3.97464999999999 >= 3.75

[08/07/20 18:36:34.543][DEBUG][Sequence Thread][SQ;] Running blocking meridian flip...

[08/07/20 18:36:34.543][DEBUG][Main Thread][SQ;] Adding sequence level notification: Running automatic pier flip...

[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] Sending Notification: Status - Running automatic pier flip...

[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] Handling monitoring event (Good Night System, Status): (fliptest) Running automatic pier flip...

[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] GNS: Sent status message to GNS ((fliptest) Running automatic pier flip...)...

[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Starting Meridian Flip Procedure

[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Skipping Solve

[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Stopping the Auto Guider

[08/07/20 18:36:34.656][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Sending Telescope command to execute meridian flip

[08/07/20 18:36:34.670][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: Pier side is West

[08/07/20 18:36:34.670][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: attempting pier flip using slew

[08/07/20 18:36:34.720][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing to J2000 RA: 14.7536210927312 (14h45m13.04s) Dec: 64.2599136085692 (64°15'35.69")

[08/07/20 18:36:34.720][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slew received J2000 coordinates, mount requires JNOW, converting...

[08/07/20 18:36:34.721][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing to JNOW RA: 14.7606388892779 Dec: 64.1805555555567

[08/07/20 18:36:41.121][DEBUG][Telescope Thread][SQ;MF;] Scope reports it is done with synchronous slew, verifying...

[08/07/20 18:36:41.153][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing has completed

[08/07/20 18:36:41.153][DEBUG][Telescope Thread][SQ;MF;] Telescope: Settling for 5 seconds

[08/07/20 18:36:46.154][DEBUG][Telescope Thread][SQ;MF;] Telescope: Settling has completed

[08/07/20 18:36:46.667][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: Failed to flip because starting pier side and ending pier side are the same!

[08/07/20 18:36:46.941][DEBUG][Main Thread][SQ;MF;] PopulateDataModel:  Transferring view to the data model...

[08/07/20 18:36:46.952][DEBUG][MF Update Thread][SQ;MF;] Performing serialize...

[08/07/20 18:36:47.168][DEBUG][Telescope Thread][SQ;MF;] Telescope thread is IDLE...

[08/07/20 18:36:47.208][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Telescope command to meridian flip has completed

[08/07/20 18:36:47.208][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Telescope failed to perform meridian flip

[08/07/20 18:36:47.841][DEBUG][Main Thread][SQ;MF;] Meridian flip was user aborted...

[08/07/20 18:36:47.880][DEBUG][Main Thread][SQ;] Adding sequence level notification: Failed to complete automatic meridian flip, aborting sequence!

[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] Sending Notification: Error - Failed to complete automatic meridian flip, aborting sequence!

[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] Handling monitoring event (Good Night System, Error): (fliptest) Failed to complete automatic meridian flip, aborting sequence!

[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] GNS: Sent error message to GNS ((fliptest) Failed to complete automatic meridian flip, aborting sequence!)...

[08/07/20 18:36:47.924][DEBUG][Pier Flip Thread][SQ;] Meridian Flip: Procedure complete

[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Blocking Pier Flip: Failed to meridian flip, aborting sequence (True)

[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Aborting sequence: Failed to meridian flip

[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Set sequence abort

[08/07/20 18:36:50.917][DEBUG][Main Thread][SQ;] Adding sequence level notification: Failed to meridian flip, aborting sequence.

 


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Leo Shatz
 

Ray, thanks for the link. I haven't yet looked at it yet (but will do shortly) - since I'm having now more serious issue : SGP suddenly cannot do any kind of flips (including in position after meridian crossing), i.e. neither auto nor manual flip works anymore. This is the typical output in SGP log file. I've tried to reboot my PC, tried different APCC/SGP versions, it just doesn't work.

[08/07/20 18:36:34.542][DEBUG][Sequence Thread][SQ;] Telescope is on the West side of the mount
[08/07/20 18:36:34.543][DEBUG][Sequence Thread][SQ;] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: 3.97464999999999 >= 3.75
[08/07/20 18:36:34.543][DEBUG][Sequence Thread][SQ;] Running blocking meridian flip...
[08/07/20 18:36:34.543][DEBUG][Main Thread][SQ;] Adding sequence level notification: Running automatic pier flip...
[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] Sending Notification: Status - Running automatic pier flip...
[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] Handling monitoring event (Good Night System, Status): (fliptest) Running automatic pier flip...
[08/07/20 18:36:34.547][DEBUG][Sequence Thread][SQ;] GNS: Sent status message to GNS ((fliptest) Running automatic pier flip...)...
[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Starting Meridian Flip Procedure
[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Skipping Solve
[08/07/20 18:36:34.653][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Stopping the Auto Guider
[08/07/20 18:36:34.656][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Sending Telescope command to execute meridian flip
[08/07/20 18:36:34.670][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: Pier side is West
[08/07/20 18:36:34.670][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: attempting pier flip using slew
[08/07/20 18:36:34.720][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing to J2000 RA: 14.7536210927312 (14h45m13.04s) Dec: 64.2599136085692 (64°15'35.69")
[08/07/20 18:36:34.720][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slew received J2000 coordinates, mount requires JNOW, converting...
[08/07/20 18:36:34.721][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing to JNOW RA: 14.7606388892779 Dec: 64.1805555555567
[08/07/20 18:36:41.121][DEBUG][Telescope Thread][SQ;MF;] Scope reports it is done with synchronous slew, verifying...
[08/07/20 18:36:41.153][DEBUG][Telescope Thread][SQ;MF;] Telescope: Slewing has completed
[08/07/20 18:36:41.153][DEBUG][Telescope Thread][SQ;MF;] Telescope: Settling for 5 seconds
[08/07/20 18:36:46.154][DEBUG][Telescope Thread][SQ;MF;] Telescope: Settling has completed
[08/07/20 18:36:46.667][DEBUG][Telescope Thread][SQ;MF;] ASCOM Telescope: Failed to flip because starting pier side and ending pier side are the same!
[08/07/20 18:36:46.941][DEBUG][Main Thread][SQ;MF;] PopulateDataModel:  Transferring view to the data model...
[08/07/20 18:36:46.952][DEBUG][MF Update Thread][SQ;MF;] Performing serialize...
[08/07/20 18:36:47.168][DEBUG][Telescope Thread][SQ;MF;] Telescope thread is IDLE...
[08/07/20 18:36:47.208][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Telescope command to meridian flip has completed
[08/07/20 18:36:47.208][DEBUG][Pier Flip Thread][SQ;MF;] Meridian Flip: Telescope failed to perform meridian flip
[08/07/20 18:36:47.841][DEBUG][Main Thread][SQ;MF;] Meridian flip was user aborted...
[08/07/20 18:36:47.880][DEBUG][Main Thread][SQ;] Adding sequence level notification: Failed to complete automatic meridian flip, aborting sequence!
[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] Sending Notification: Error - Failed to complete automatic meridian flip, aborting sequence!
[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] Handling monitoring event (Good Night System, Error): (fliptest) Failed to complete automatic meridian flip, aborting sequence!
[08/07/20 18:36:47.920][DEBUG][Sequence Thread][SQ;] GNS: Sent error message to GNS ((fliptest) Failed to complete automatic meridian flip, aborting sequence!)...
[08/07/20 18:36:47.924][DEBUG][Pier Flip Thread][SQ;] Meridian Flip: Procedure complete
[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Blocking Pier Flip: Failed to meridian flip, aborting sequence (True)
[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Aborting sequence: Failed to meridian flip
[08/07/20 18:36:50.915][DEBUG][Sequence Thread][SQ;] Set sequence abort
[08/07/20 18:36:50.917][DEBUG][Main Thread][SQ;] Adding sequence level notification: Failed to meridian flip, aborting sequence.
 


“Other” brand flatteners/reducers w’ AP refractors

Logan Tudor
 

Hi,
Has anyone ever tried (or currently using) the Takahashi #67 4” flattener with the AP130/GTX; or Tak #645 4” super reducer (somewhat similar to APs dedicated “quad” reducer) and gotten good results?


Re: IP address of an AP1600 ?

Pete Mumbower
 

Unless your computer is setup with DHCP services, the mount will not get an address. Plugging a router (typically people will use home wifi router), which is setup to handle DHCP out of the box, will resolve this. I am assuming if there is a computer already being used, there is a router somewhere. Just plug the mount into that to have it get an IP address. You can then log into the router and look at all the devices connected and what IP address is assigned to it.

Hope that help,
Pete


Re: Please Welcome Mike!

Jim Roberts
 

Welcome Mike! Great group and great virtual conversation.

Sincerely,

James Roberts

------ Original Message ------
From: "Karen Christen" <karen@...>
Sent: 8/5/2020 12:47:40 PM
Subject: [ap-gto] Please Welcome Mike!

Hello Astronuts,

 

I’d like to introduce you to Mike Hanson, our Servo Engineer.  Mike is an Electrical Engineer by background, has 30+ years in the aerospace industry, and has been moonlighting with us since 1994.  We’re so excited to share that as of this week Mike has joined our team full-time!  He’s super-smart, an integral part of our mount development team, and an all-around great guy.  You’ll be seeing more of Mike here on the GTO user group as he responds to some of your questions.  Please make him welcome.

Karen C

AP

 


--
Karen Christen
Astro-Physics


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Ray Gralak
 

Hi Leo,

Take a look at this video. It shows how to set up the mount to flip before the meridian. The only additional thing you will need to do is to enable the checkbox to send the flip point to SGPro, which looks like you are doing in your screenshot.

https://www.youtube.com/watch?v=eBUj1WgFf3k

-Ray Gralak
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Leo Shatz
Sent: Friday, August 7, 2020 4:22 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Pier flip before meridian crossing is not possible with SGP and Mach1

Hello Ray,

Sorry for delay in posting reply. The issue I raised in this post was about inability of SGP to perform auto flip
BEFORE meridian crossing. I've learned how to setup simple meridian limits in APCC, so that SGP can perform
delayed flips when the scope has already passed meridian, with all safety limits in place. However, in some
situations I'd like to schedule the auto flip (and monitor it) earlier - before meridian is crossed. I'm attaching a
screenshot showing the problem. I've setup Flip Offset in APCC to shift the flip to the East, but SGP refuses to
perform the auto flip and aborts the sequence:




Another screenshot shows a warning message from SGP before running the sequence when I change Flip
Offset, which seems to be related:




At the same time, when SGP aborts the sequence, I'm able to perform manually from APCC by pressing "Pier
Flip" button.

I'd like to know what I'm missing here.

Thanks,

Leo


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Leo Shatz
 
Edited

And also, I forgot to mention it and while this error happened to me again - sometimes SGP fails to perform the flip even when telescope has already crossed meridian. Please see attached screenshot. I have no idea what is going on. When I hit "Pier Flip" button in APCC - after this error happens, the mount performs flip without any problem. As for SGP, it sends slew command, I can see the APCC small dialog box saying it's slewing with Red Abort button flushing for just few moments and then it disappears - I wasn't quick enough to capture it in this screenshot.

Also, when both SGP and APCC say that mount is slewing - I don't hear a sound from Mach1 - it doesn't move at all. I'm also able to slew manually - both from APCC and SGP scope controls.


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Leo Shatz
 

I'm attaching the screenshots with full resolution.


Re: IP address of an AP1600 ?

christian viladrich
 

Hi Mark,

Thanks for this !

Regarding test n°1 : the yellow LED is permanently on. The green LED blinks occasionally.  Just a a reminder, the mount is directly connected to the computer (i.e. no router).

Regarding test n°2 : we will have a look at it (and maybe try with a router).

Kind regards

Christian

Le 05/08/2020 à 14:07, michaeljhanson@... a écrit :
Hi Christian,

An IP Address of 0.0.0.0 means usually one of two things:
1) Either the low-level link is not established.  Please check the small LED's on the RJ-45.  With the unit RJ-45 "plugged in", one LED should be lit all the time, and the other should blink occasionally.  If you are not getting this, the connection issue needs to be dealt with before an IP Address means anything.  The LED's are dim in broad daylight, otherwise they are blinding in pitch darkness.
2) Or, the unit is configured to be one a network (DHCP client), and DHCP has not timed out (30 seconds).  When your computer and unit are both asking for IP addresses, thinking they are supposed to be on a network, but there's no DHCP server, they cannot communicate.  You can plug the unit into any network/router the computer is connected to (doesn't matter if the computer is connected via WiFi or cable).  

If you have a low-level link, and want to direct connect to the unit, wait 30 seconds for DHCP to timeout, and verify that you computer defaults to the link-local subnet (computer IP address = 169.254.xxx.xxx).  This can be checked using "ipconfig" in a DOS window.

There are other ways to configure the unit (or the PC) to allow them to "direct connect", be on the same sub-net, without waiting 30 seconds.  This can be a continuation topic if needed.  Please verify 1 and 2 first to make sure the unit's Ethernet is working.

Regards,
Mike Hanson


Re: Pier flip before meridian crossing is not possible with SGP and Mach1

Leo Shatz
 

Hello Ray,

Sorry for delay in posting reply. The issue I raised in this post was about inability of SGP to perform auto flip BEFORE meridian crossing. I've learned how to setup simple meridian limits in APCC, so that SGP can perform delayed flips when the scope has already passed meridian, with all safety limits in place. However, in some situations I'd like to schedule the auto flip (and monitor it) earlier - before meridian is crossed. I'm attaching a screenshot showing the problem. I've setup Flip Offset in APCC to shift the flip to the East, but SGP refuses to perform the auto flip and aborts the sequence:

 


Another screenshot shows a warning message from SGP before running the sequence when I change Flip Offset, which seems to be related:




At the same time, when SGP aborts the sequence, I'm able to perform manually from APCC by pressing "Pier Flip" button.

I'd like to know what I'm missing here.

Thanks,

Leo


Re: LMFHDT-AP question

Christopher Erickson
 

4 is correct. It adapts to several different AP mount bases and offers multiple orientations.

4 bolts is plenty sufficient 


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


On Thu, Aug 6, 2020, 6:34 PM Shailesh Trivedi <strivedi@...> wrote:
I bought a used AP1100 from astromart. It also came with the Losmandy heavy-duty tripod by AP which includes the 119FSA with fasteners. 

I can only bolt-on 4 screws on the 119FSA to the tripod, since only 4 holes align and the 119FSA has 8 holes. Is this by design or am I missing something in how I align it on the flat surface of the Losmand tripod? 

Shailesh


LMFHDT-AP question

Shailesh Trivedi
 

I bought a used AP1100 from astromart. It also came with the Losmandy heavy-duty tripod by AP which includes the 119FSA with fasteners. 

I can only bolt-on 4 screws on the 119FSA to the tripod, since only 4 holes align and the 119FSA has 8 holes. Is this by design or am I missing something in how I align it on the flat surface of the Losmand tripod? 

Shailesh


Re: Last night imaging - Stars of M13's core

Tony Benjamin <tonybenjamin@...>
 

Hi Rolando,

 

Can you tell me what your image scale is for this setup and the length of your images? Also, what FWHM are your stars and what eccentricity were your stars?

 

 

Tony

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of uncarollo2 <chris1011@...> via groups.io
Sent: August 5, 2020 6:31 PM
To: main@ap-gto.groups.io; main@ap-ug.groups.io
Subject: [ap-gto] Last night imaging - Stars of M13's core

 

Hi Astronuts,

 

More unguided imaging with the 17" Astrograph on the 1600 Encoder mount:

 

Closeup of the stars in the core of M13, taken during good seeing conditions, with AP 17" F8 Astrograph. Stars separated by 1 arc second are resolved with dark space between. 1600 AE Encoder mount was used to take 20 Luminance and 10 each RGB images, unguided.

 

Rolando


Last night imaging - Stars of M13's core

Roland Christen
 

Hi Astronuts,

More unguided imaging with the 17" Astrograph on the 1600 Encoder mount:

https://www.astrobin.com/full/pmc2n2/0/?nc=Uncarollo

Closeup of the stars in the core of M13, taken during good seeing conditions, with AP 17" F8 Astrograph. Stars separated by 1 arc second are resolved with dark space between. 1600 AE Encoder mount was used to take 20 Luminance and 10 each RGB images, unguided.

Rolando

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