Meridian flip - software or firmware issue? #iEXOS-100 #ASCOM #FIRMWARE #pmc-eight


Karol Trepala
 

I'm using iExos-100 with N.I.N.A and it works well. Last night I have got an opportunity to use first time meridian flip function. This also start as should, telescope was rotated and roughly set in apprpriate position, on the target. Unfortunately, when Nina made plate solving and tried to recenter the target. mount instead of small position correction started to rotate in the direction of tripod. Fortunately I was able to unplug power supply before my camera clashed with tripod. It looked like the mount received new (corrected) coordinates, slighty shifted from current position, but instead of small movement it decided to set this new position by 360deg rotation. Could that be some issue with N.I.N.A (I don't know what settings can I adjust to avoid such situation in the future) or some mount firmware issue?


Jerry Hubbell - Explore Scientific VP Engineering
 

One of the things to keep in mind that is a rare occurrence (it has been reported on the forum in the past) is that if you do a Meridian flip and try and solve the new position too soon, that the scope may still be pointed to the East instead of to the West as expected. This will cause the mount to try and point back to the West and screw up because even though the PierSide calculation shows it is on the Western side, the coordinates to point to are on the Eastern side. 

The fix is to delay at least 1 minute to perform the plate solve to ensure the current position is actually to the West of the Meridian. This is dependent on the mount's performance in re pointing to the target after the Meridian Flip, YMMV.

Thanks 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Jennifer Shelly
 

On Tue, May 18, 2021 at 03:45 AM, Karol Trepala wrote:
Could that be some issue with N.I.N.A (I don't know what settings can I adjust to avoid such situation in the future)
Do you have Pier Side of Mount turned on or off in NINA?
 
--
Sincerely,

Jennifer Shelly
AstroPorch, VA

Mounts
: ES PMC-8 G-11, ES PMC-8 iEXOS-100
Scopes: ES ED127 FCD-100, Askar FRA 400, ES Levy Comet Hunter, ES N208CF, QHY Mini Guide Scope, Solomark F60 Guide Scope
Cameras: QHY600M, QHY128C, QHY168C
Misc: MoonLite CFL 2.5 / High Res Stepper / V2 Mini Controller, Baader SteelTrack NT / SteelDrive II, Baader UFC, Optolong 2" L-Pro / L-eNhance, QHY CFW3-L, Baader 2” LRGBSHO CCD
Imaging Software:  NINA, APT, SharpCap Pro
Processing Software: PixInsight, Lightroom, Premiere Elements


Wes Mcdonald
 

Should be off I believe
--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100
ES ED 127, 10" LX200GPS+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


Luiz Sanches
 

Meridian flip never works for me. When I need to do, I prefer to manually move the mount to other side and make many plat solves until get the target again. 
I use APT and always failed to meridian flip.


Walter Vinci
 

This is something I wanted to ask at some point too. Manually asking APT to perform a meridian flip with my Exos2 gives an error and doesn’t work. Just wandering if this is my problem or it is a general issue.

It is nice to be able to be point a target before it passes the meridian and being already ‘flipped’ so that there is no need to interrupt imaging. 


Walter

On May 18, 2021, at 9:02 AM, Luiz Sanches via groups.io <luizfsanches@...> wrote:

Meridian flip never works for me. When I need to do, I prefer to manually move the mount to other side and make many plat solves until get the target again. 
I use APT and always failed to meridian flip.

--
———

Walter Vinci

ES EXOS2-GT PMC-Eight
ES ED80
Starfield 0.8 Field Flattener/Reducer.
ZWO ASI290mm-mini & Orion 50mm Guide Scope
Canon EOS Rebel SL1
SharpCap, APT, PHD2, SiriL, Stellarium


Karol Trepala
 

Thanks for advice and explanation. I will test it with the next clear sky.


Jerry Hubbell - Explore Scientific VP Engineering
 

On Tue, May 18, 2021 at 11:24 AM, Walter Vinci wrote:
It is nice to be able to be point a target before it passes the meridian and being already ‘flipped’ so that there is no need to interrupt imaging. 
Hi Walter,

If you want to do a Meridian flip "early" you can only do that manually, you cannot slew do this with a "goto" or point command with an ASCOM application because the goto always calculates the current side of pier of the object prior to slewing. What you have to do is:
1. Point to an object that has passed the Meridian (in the West)
2. Manually move the mount back East of the Meridian to the desired Target.
3. Start imaging as desired.

The result is that the counterweight will be above the telescope and is "up" instead of "down" which is not a standard mount state that you would normally want.
Other than that it should be fine.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Walter Vinci
 

Hi Jerry,

Thanks, that should work. My understanding was that APT could automatically take care of this with a goto move if I clicked in manual meridian flip.

ps: I found that starting with the counterweight up is fine with my set up as long as I start within 1h of the meridian pass.


Walter

On May 18, 2021, at 1:25 PM, Jerry Hubbell - Explore Scientific VP Engineering <jrh@...> wrote:

On Tue, May 18, 2021 at 11:24 AM, Walter Vinci wrote:
It is nice to be able to be point a target before it passes the meridian and being already ‘flipped’ so that there is no need to interrupt imaging. 
Hi Walter,

If you want to do a Meridian flip "early" you can only do that manually, you cannot slew do this with a "goto" or point command with an ASCOM application because the goto always calculates the current side of pier of the object prior to slewing. What you have to do is:
1. Point to an object that has passed the Meridian (in the West)
2. Manually move the mount back East of the Meridian to the desired Target.
3. Start imaging as desired.

The result is that the counterweight will be above the telescope and is "up" instead of "down" which is not a standard mount state that you would normally want.
Other than that it should be fine.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


--
———

Walter Vinci

ES EXOS2-GT PMC-Eight
ES ED80
Starfield 0.8 Field Flattener/Reducer.
ZWO ASI290mm-mini & Orion 50mm Guide Scope
Canon EOS Rebel SL1
SharpCap, APT, PHD2, SiriL, Stellarium


Jerry Hubbell - Explore Scientific VP Engineering
 

On Tue, May 18, 2021 at 03:25 PM, Jerry Hubbell - Explore Scientific VP Engineering wrote:
If you want to do a Meridian flip "early" you can only do that manually
I forgot to state also that there is a better alternative to doing a Meridian Flip "on-time" The PMC-EIght and driver is fully capable of tracking up to an hour past the Meridian (depending on mount/scope configuration) and if you are in the middle of an imaging run, it is best to not schedule the Meridian flip until at least 5 minutes past the Meridian. I think that this should be possible if you are using an automation program like NINA or APT (I don't know). I use MaxIm dl and it allows me to delay the meridian flip.  This is a better approach than trying to do the flip "early" and will not run into the issue when trying to do a plate solve immediately after the flip causing a pier-side miscalculation.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Walter Vinci
 

Sorry, I should have explained better my use case. Sometimes I found myself ready to start imaging a subject that is about to pass the meridian (say in 30mins), but didn’t quite. Then I would be happy to start imaging pre-flipped, if you wish, so that I do not have to interrupt the imaging session in between. 

In this case goto doesn’t work since ASCOM will tell the mount to orient the counterweight down, as it should. No biggie, as you said a manual slew will work. I was just thinking whether a manual flip commanded by APT is a functionality I misunderstood, if it is a bug in APT or there is a problem with the ASCOm driver.

Thanks anyway for the feedback!
W.


On May 18, 2021, at 1:49 PM, Jerry Hubbell - Explore Scientific VP Engineering <jrh@...> wrote:

On Tue, May 18, 2021 at 03:25 PM, Jerry Hubbell - Explore Scientific VP Engineering wrote:
If you want to do a Meridian flip "early" you can only do that manually
I forgot to state also that there is a better alternative to doing a Meridian Flip "on-time" The PMC-EIght and driver is fully capable of tracking up to an hour past the Meridian (depending on mount/scope configuration) and if you are in the middle of an imaging run, it is best to not schedule the Meridian flip until at least 5 minutes past the Meridian. I think that this should be possible if you are using an automation program like NINA or APT (I don't know). I use MaxIm dl and it allows me to delay the meridian flip.  This is a better approach than trying to do the flip "early" and will not run into the issue when trying to do a plate solve immediately after the flip causing a pier-side miscalculation.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!



--
———

Walter Vinci

ES EXOS2-GT PMC-Eight
ES ED80
Starfield 0.8 Field Flattener/Reducer.
ZWO ASI290mm-mini & Orion 50mm Guide Scope
Canon EOS Rebel SL1
SharpCap, APT, PHD2, SiriL, Stellarium


Andrew Houseman
 

This is my exact use case also.  In fact, my east horizon is just 10-15 degrees off the meridian due to trees.  I would love to have the option of the mount always on the 'flipped' side.  So it's not "track past the meridian" but rather "go-to and start tracking before the meridian".

In other words, a user settable filp point.


On Tue, May 18, 2021, 4:03 PM Walter Vinci <wltvinci@...> wrote:
Sorry, I should have explained better my use case. Sometimes I found myself ready to start imaging a subject that is about to pass the meridian (say in 30mins), but didn’t quite. Then I would be happy to start imaging pre-flipped, if you wish, so that I do not have to interrupt the imaging session in between. 

In this case goto doesn’t work since ASCOM will tell the mount to orient the counterweight down, as it should. No biggie, as you said a manual slew will work. I was just thinking whether a manual flip commanded by APT is a functionality I misunderstood, if it is a bug in APT or there is a problem with the ASCOm driver.

Thanks anyway for the feedback!
W.


On May 18, 2021, at 1:49 PM, Jerry Hubbell - Explore Scientific VP Engineering <jrh@...> wrote:

On Tue, May 18, 2021 at 03:25 PM, Jerry Hubbell - Explore Scientific VP Engineering wrote:
If you want to do a Meridian flip "early" you can only do that manually
I forgot to state also that there is a better alternative to doing a Meridian Flip "on-time" The PMC-EIght and driver is fully capable of tracking up to an hour past the Meridian (depending on mount/scope configuration) and if you are in the middle of an imaging run, it is best to not schedule the Meridian flip until at least 5 minutes past the Meridian. I think that this should be possible if you are using an automation program like NINA or APT (I don't know). I use MaxIm dl and it allows me to delay the meridian flip.  This is a better approach than trying to do the flip "early" and will not run into the issue when trying to do a plate solve immediately after the flip causing a pier-side miscalculation.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!



--
———

Walter Vinci

ES EXOS2-GT PMC-Eight
ES ED80
Starfield 0.8 Field Flattener/Reducer.
ZWO ASI290mm-mini & Orion 50mm Guide Scope
Canon EOS Rebel SL1
SharpCap, APT, PHD2, SiriL, Stellarium