Date
1 - 20 of 22
Tracking difficulties
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Thomas Haugh
I have finally gotten the opportunity to install my new AP1600. I am having difficulty getting the tracking accurate. Symptoms: Stars trailed on 30 second exposure. Telescope appears to slew correctly but does not end up on the target. I have opened the RA gear box and the gear on the motor turns while in sidereal mode. When parking (to park 4) the telescope does not return to counterweight bar horizontal. I took two 5 second unguided exposures 5 minutes apart and solved each. During these exposures the driver indicated sidereal and the keypad indicated Side. Info on each follows: ----------------------------------------------- DATE-OBS = '2016-01-12T02:54:23.00' / [ISO 8601] UTC date/time of exposure start Locating stars in image Looking up stars in catalog Solving using 1989 image and 703 catalog stars Matched 314 of 1989 image and 703 catalog stars; Average residual 0.2 arcsec; order 4 RA 05h 52m 09.2s, Dec +32° 32' 45.8" Pos Angle +89° 35.5', FL 1353.7 mm, 1.04"/Pixel ----------------------------------------------- DATE-OBS = '2016-01-12T02:59:50' / [ISO 8601] UTC date/time of exposure start Locating stars in image Looking up stars in catalog Solving using 1911 image and 703 catalog stars Matched 319 of 1911 image and 703 catalog stars; Average residual 0.2 arcsec; order 4 RA 05h 52m 24.3s, Dec +32° 32' 48.0" Pos Angle +89° 35.4', FL 1353.8 mm, 1.04"/Pixel ----------------------------------------------- Current configuration: Maxim DL(5.21) -> Astro-Physics V2 Driver v.5.07.02 -> AP1600 The driver display indicates firmware version S. Using park 4. Computer to mount is direct straight through RS232. (no USB) Camera/Focuser control cables routed through the mount. (no obvious external snags) No connection to mount guide port. Current telescope: Orion 10" classical newtonian @ f/5.3 . SBIG ST10-XME. I am unsure of the weight, but nowhere near the mounts stated capacity. The mount is very stiff with the clutches released several turns, but the balance 'feels' the same. I am awaiting a pull scale to further refine the balance. Current date/time verified to PC. PC time updates via NTP. Used PEMPRO Polar Alignment to align mount. Over 5 minutes the application requests corrections to either axis between 0.5-0.7 arc minutes. Power supply: PS15V12AC The power supply feeds the mount exclusively. Voltage reads 14.96 vdc. The LED on the control box is always red. ----------------------------------------------- Observations during troubleshooting: Tracking rate changes from the keypad are reflected on the Astro-Physics V2 Driver. Tracking rate changes on the driver are not reflected on the keypad T: display. If the keypad showed 8=T:Side, it did not change. However, when the driver indicates stop and the keypad indicates Side the mount is indeed stopped. A 5 second exposure trails. The keypad Az/Alt does not change while the RA does. The keypad RA/Dec/Az/Alt values match the driver. I don't know if any of this is pertinent to the tracking problem; just passing on the observation. ----------------------------------------------- Any help would be appreciated. Tom Haugh |
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Roland Christen
1) check to see if you have turned PEM to ON
2) Are you getting trailing in both RA and Dec? If so, you may not be properly polar aligned.
3) Do you get trailing nearer to the horizon, or straight up?
Things to keep in mind: the mount's servo motors do not run slow or fast. They either run at the sidereal rate or not at all. There is no in between, regardless of the temperature. Having a stiff axis with the clutches loosened is normal. The clutches are not part of the drive train, so have no effect whatsoever on the drive gear. balance is not required, and no amount of unbalance for a light or medium weight scope will ever cause the motors to run at anything other than exactly sidereal rate.
Finally, even a slight polar misalignment will cause stars to trail in a 30 second exposure. There is no getting around the fact that you will need to guide with some kind of guiding system. Newtonians especially will have differential flexure that shows up even in 30 seconds, so there is no way to do unguided imaging without using extensive modeling software.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 12:37 am Subject: [ap-gto] Tracking difficulties I have finally gotten the opportunity to install my new AP1600. I am having difficulty getting the tracking accurate.
Symptoms:
Stars trailed on 30 second exposure.
Telescope appears to slew correctly but does not end up on the target.
I have opened the RA gear box and the gear on the motor turns while in sidereal mode.
When parking (to park 4) the telescope does not return to counterweight bar horizontal.
I took two 5 second unguided exposures 5 minutes apart and solved each. During these exposures
the driver indicated sidereal and the keypad indicated Side. Info on each follows:
-----------------------------------------------
DATE-OBS = '2016-01-12T02:54:23.00' / [ISO 8601] UTC date/time of exposure start
Locating stars in image
Looking up stars in catalog
Solving using 1989 image and 703 catalog stars
Matched 314 of 1989 image and 703 catalog stars;
Average residual 0.2 arcsec; order 4
RA 05h 52m 09.2s, Dec +32° 32' 45.8"
Pos Angle +89° 35.5', FL 1353.7 mm, 1.04"/Pixel
-----------------------------------------------
DATE-OBS = '2016-01-12T02:59:50' / [ISO 8601] UTC date/time of exposure start
Locating stars in image
Looking up stars in catalog
Solving using 1911 image and 703 catalog stars
Matched 319 of 1911 image and 703 catalog stars;
Average residual 0.2 arcsec; order 4
RA 05h 52m 24.3s, Dec +32° 32' 48.0"
Pos Angle +89° 35.4', FL 1353.8 mm, 1.04"/Pixel
-----------------------------------------------
Current configuration:
Maxim DL(5.21) -> Astro-Physics V2 Driver v.5.07.02 -> AP1600
The driver display indicates firmware version S.
Using park 4.
Computer to mount is direct straight through RS232. (no USB)
Camera/Focuser control cables routed through the mount. (no obvious external snags)
No connection to mount guide port.
Current telescope:
Orion 10" classical newtonian @ f/5.3 .
SBIG ST10-XME.
I am unsure of the weight, but nowhere near the mounts stated capacity.
The mount is very stiff with the clutches released several turns, but the
balance 'feels' the same. I am awaiting a pull scale to further refine the
balance.
Current date/time verified to PC. PC time updates via NTP.
Used PEMPRO Polar Alignment to align mount.
Over 5 minutes the application requests corrections to either axis between 0.5-0.7 arc minutes.
Power supply: PS15V12AC
The power supply feeds the mount exclusively.
Voltage reads 14.96 vdc.
The LED on the control box is always red.
-----------------------------------------------
Observations during troubleshooting:
Tracking rate changes from the keypad are reflected on the Astro-Physics V2 Driver.
Tracking rate changes on the driver are not reflected on the keypad T: display. If the
keypad showed 8=T:Side, it did not change. However, when the driver indicates stop and
the keypad indicates Side the mount is indeed stopped. A 5 second exposure trails. The
keypad Az/Alt does not change while the RA does. The keypad RA/Dec/Az/Alt
values match the driver. I don't know if any of this is pertinent to the tracking problem; just
passing on the observation.
-----------------------------------------------
Any help would be appreciated.
Tom Haugh
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Thomas Haugh
Rolando,
1. The PEM is off. I attempted a PEMPRO run. The Y axis values appear as expected. The X values within seconds, run off the top of the graph. X values quickly exceed 90. 2. The trailing is only E-W. 3. I am limited to a fairly narrow FOV. So all my observing is pretty much zenith +/- 35 degrees. I am concerned with your statement about 30 second unguided exposures being trailed. I was routinely able to get untrailed 30 second unguided exposures from the mount I am upgrading from. I couldn't do 60, but 30 was no problem. Did I just happen to hit the right mis-alignment to accomplish that? This was using the same telescope/camera/rings/dovetail that is on the 1600 now. Others on this board praise 5 minute unguided exposures. Does it take the encoder system to accomplish that? No argument here, I'm just trying to understand what I am seeing. Thanks for the quick reply. Tom |
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Roland Christen
I am simply guessing because there was not enough information. In my mind trailing can mean 1 arc second error in 30 seconds, or 5 minutes. Trailing can also occur when the motor is turned off. In that case you get 15 arc second trailing in one second (90 arc seconds in 6 seconds of time).
X values quickly exceed 90? What does this mean? 90 arc seconds? That sounds like tracking is turned off completely. You may have plugged in a guider cable that either has a short, or your guide camera is not powered on and therefore sending a signal to the mount to go faster or slower than sidereal.
I would remove all external plugs from the CP3 servo and start fresh with nothing plugged in except the keypad. Forget doing a PEMPro run until you have figured out what software is sending bogus command to your mount. Remove all external cables except the keypad and those going to the motors.
Start from the basics and work your way up to full external control.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 10:50 am Subject: Re: [ap-gto] Tracking difficulties Rolando, 1. The PEM is off. I attempted a PEMPRO run. The Y axis values appear as expected. The X values within seconds, run off the top of the graph. X values quickly exceed 90.
2. The trailing is only E-W.
3. I am limited to a fairly narrow FOV. So all my observing is pretty much zenith +/- 35 degrees.
I am concerned with your statement about 30 second unguided exposures being trailed. I was routinely able to get untrailed 30 second unguided exposures from the mount I am upgrading from. I couldn't do 60, but 30 was no problem. Did I just happen to hit the right mis-alignment to accomplish that? This was using the same telescope/camera/rings/dovetail that is on the 1600 now. Others on this board praise 5 minute unguided exposures. Does it take the encoder system to accomplish that?
No argu
ment here, I'm just trying to understand what I am seeing.
Thanks for the quick reply.
Tom
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Roland Christen
Just thought of something else: What color is the LED on the CP3 servo controller?
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 10:50 am Subject: Re: [ap-gto] Tracking difficulties Rolando, 1. The PEM is off. I attempted a PEMPRO run. The Y axis values appear as expected. The X values within seconds, run off the top of the graph. X values quickly exceed 90.
2. The trailing is only E-W.
3. I am limited to a fairly narrow FOV. So all my observing is pretty much zenith +/- 35 degrees.
I am concerned with your statement about 30 second unguided exposures being trailed. I was routinely able to get untrailed 30 second unguided exposures from the mount I am upgrading from. I couldn't do 60, but 30 was no problem. Did I just happen to hit the right mis-alignment to accomplish that? This was using the same telescope/camera/rings/dovetail that is on the 1600 now. Others on this board praise 5 minute unguided exposures. Does it take the encoder system to accomplish that?
No argu
ment here, I'm just trying to understand what I am seeing.
Thanks for the quick reply.
Tom
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Thomas Haugh
It is about the same color red as the keypad display. Stays that color throughout slew and track.
The keypad does not have the 1600 as an option for mount type. I assume you leave it at 1200? Tom |
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Roland Christen
-----Original Message-----
From: chris1011 To: ap-gto Sent: Tue, Jan 12, 2016 11:22 am Subject: Re: [ap-gto] Tracking difficulties I am simply guessing because there was not enough information. In my mind trailing can mean 1 arc second error in 30 seconds, or 5 minutes. Trailing can also occur when the motor is turned off. In that case you get 15 arc second trailing in one second (90 arc seconds in 6 seconds of time).
X values quickly exceed 90? What does this mean? 90 arc seconds? That sounds like tracking is turned off completely. You may have plugged in a guider cable that either has a short, or your guide camera is not powered on and therefore sending a signal to the mount to go faster or slower than sidereal.
I would remove all external plugs from the CP3 servo and start fresh with nothing plugged in except the keypad. Forget doing a PEMPro run until you have figured out what software is sending bogus command to your mount. Remove all external cables except the keypad and those going to the motors.
Start from the basics and work your way up to full external control.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] <ap-gto@...> To: ap-gto <ap-gto@...> Sent: Tue, Jan 12, 2016 10:50 am Subject: Re: [ap-gto] Tracking difficulties Rolando, 1. The PEM is off. I attempted a PEMPRO run. The Y axis values appear as expected. The X values within seconds, run off the top of the graph. X values quickly exceed 90.
2. The trailing is only E-W.
3. I am limited to a fairly narrow FOV. So all my observing is pretty much zenith +/- 35 degrees.
I am concerned with your statement about 30 second unguided exposures being trailed. I was routinely able to get untrailed 30 second unguided exposures from the mount I am upgrading from. I couldn't do 60, but 30 was no problem. Did I just happen to hit the right mis-alignment to accomplish that? This was using the same telescope/camera/rings/dovetail that is on the 1600 now. Others on this board praise 5 minute unguided exposures. Does it take the encoder system to accomplish that?
No argu
ment here, I'm just trying to understand what I am seeing.
Thanks for the quick reply.
Tom
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Silly suggestion but make sure that you have tracking set to Sidereal
and not to Stop, Lunar or Solar.
Christopher Erickson
Consulting Engineer Summit Kinetics Waikoloa, HI 96738 www.summitkinetics.com From: ap-gto@... [mailto:ap-gto@...] Sent: Tuesday, January 12, 2016 7:51 AM To: ap-gto@... Subject: Re: [ap-gto] Tracking difficulties The keypad does not have the 1600 as an option for mount type. I
assume you leave it at 1200?
Tom
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Steven
You might want to re-check the N/S switch. It's a 3-way switch - make sure it's hard over on N.
Steve From: ap-gto@... on behalf of chris1011@... [ap-gto]
Sent: Tuesday, 12 January 2016 12:22 p.m. To: ap-gto@... Subject: Re: [ap-gto] Tracking difficulties I am simply guessing because there was not enough information. In my mind trailing can mean 1 arc second error in 30 seconds,
or 5 minutes. Trailing can also occur when the motor is turned off. In that case you get 15 arc second trailing in one second (90 arc seconds in 6 seconds of time).
X values quickly exceed 90? What does this mean? 90 arc seconds? That sounds like tracking is turned off completely. You may have plugged in a guider cable that either has a short, or your guide camera is not powered on and
therefore sending a signal to the mount to go faster or slower than sidereal.
I would remove all external plugs from the CP3 servo and start fresh with nothing plugged in except the keypad. Forget doing a PEMPro run until you have figured out what software is sending bogus command to your mount. Remove
all external cables except the keypad and those going to the motors.
Start from the basics and work your way up to full external control.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 10:50 am Subject: Re: [ap-gto] Tracking difficulties Rolando, 1. The PEM is off. I attempted a PEMPRO run. The Y axis values appear as expected. The X values within seconds, run off the top of the graph. X values quickly exceed 90.
2. The trailing is only E-W.
3. I am limited to a fairly narrow FOV. So all my observing is pretty much zenith +/- 35 degrees.
I am concerned with your statement about 30 second unguided exposures being trailed. I was routinely able to get untrailed 30 second unguided exposures from the mount I am upgrading from. I couldn't do 60, but 30 was no problem.
Did I just happen to hit the right mis-alignment to accomplish that? This was using the same telescope/camera/rings/dovetail that is on the 1600 now. Others on this board praise 5 minute unguided exposures. Does it take the encoder system to accomplish
that?
No argu ment here, I'm just trying to understand what I am seeing.
Thanks for the quick reply.
Tom
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Joe Zeglinski
Steve,
You peaked my curiosity. The N/S switch on the CP3 panel
is a “3-way” ?
Checked mine, and it is a slide switch with no click stops, so I assume any
position slightly left or right of center, won’t use any ambiguous “center
contacts” position.
Mind you, it is a “soft” slider – a left/right “click
stop” might have been more assertive. But being recessed, I can’t see it sliding
over on its own, between setups.
Joe
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Steven
The problem bedevilled me too. I'm in S and when I first got the mount, I slided the switch to (what I thought was) S. I slided it one 'click'. Still, I was having a real headache, just like Joe. Looked about the same as his desctriptions.
So even after ignoring good advice from a friend, I ignored it in utter frustration. Then I stuck the dull end of a pen into the slot and tried to assure the switch was on S. It clicked, so obviously it was in neutral position. I couldn't believe it - I even tried it again to be sure. Nevermind my definition of 3-way, or whatever. It has 3 stops. I'd hit #2 in error.
Just an idea, why not try it, it won't cost anything?
Steve From: ap-gto@... on behalf of 'Joseph Zeglinski' J.Zeglinski@... [ap-gto]
Sent: Tuesday, 12 January 2016 4:47 p.m. To: ap-gto@... Subject: Re: [ap-gto] Tracking difficulties Steve,
You peaked my curiosity. The N/S switch on the CP3 panel is a “3-way” ?
Checked mine, and it is a slide switch with no click stops, so I assume any position slightly left or right of center, won’t use any ambiguous “center contacts” position.
Mind you, it is a “soft” slider – a left/right “click stop” might have been more assertive. But being recessed, I can’t see it sliding over on its own, between setups.
Joe
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Steven
Joe, BTW, you have to turn off the machine and start up again to see the change. Hope it helps.
Steve From: ap-gto@... on behalf of 'Joseph Zeglinski' J.Zeglinski@... [ap-gto]
Sent: Tuesday, 12 January 2016 4:47 p.m. To: ap-gto@... Subject: Re: [ap-gto] Tracking difficulties Steve,
You peaked my curiosity. The N/S switch on the CP3 panel is a “3-way” ?
Checked mine, and it is a slide switch with no click stops, so I assume any position slightly left or right of center, won’t use any ambiguous “center contacts” position.
Mind you, it is a “soft” slider – a left/right “click stop” might have been more assertive. But being recessed, I can’t see it sliding over on its own, between setups.
Joe
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Thomas Haugh
Just to start at the basics.
The keypad does not have 1600 as an option for mount type. What is the correct selection for the 1600 mount? Tom |
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Mike Shade
In reading the manual and such for the 1600 (which is still in boxes) I seem to recall use the 1200 settings...
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: Tuesday, January 12, 2016 8:41 PM To: ap-gto@... Subject: [ap-gto] Re: Tracking difficulties Just to start at the basics. The keypad does not have 1600 as an option for mount type. What is the correct selection for the 1600 mount? Tom [Non-text portions of this message have been removed] |
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Roland Christen
Use the 1200 setting. Nothing is really impacted except the backlash settings which you would not be using with today's imaging equipment.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 9:40 pm Subject: [ap-gto] Re: Tracking difficulties Just to start at the basics. The keypad does not have 1600 as an option for mount type. What is the correct selection for the 1600 mount?
Tom
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Roland Christen
It makes zero difference which setting you use nowadays. The setting originally was for manual guiding which nobody uses any more.
Rolando
-----Original Message-----
From: 'Mike Shade' mshade@q.com [ap-gto] To: ap-gto Sent: Tue, Jan 12, 2016 10:15 pm Subject: RE: [ap-gto] Re: Tracking difficulties In reading the manual and such for the 1600 (which is still in boxes) I seem to recall use the 1200 settings... 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: Tuesday, January 12, 2016 8:41 PM To: ap-gto@... Subject: [ap-gto] Re: Tracking difficulties Just to start at the basics. The keypad does not have 1600 as an option for mount type. What is the correct selection for the 1600 mount? Tom ------------------------------------ Posted by: "Mike Shade" <mshade@q.com> ------------------------------------ To UNSUBSCRIBE, or for general information on the ap-gto list see http://groups.yahoo.com/group/ap-gto ------------------------------------ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/ap-gto/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/ap-gto/join (Yahoo! ID required) <*> To change settings via email: ap-gto-digest@... ap-gto-fullfeatured@... <*> To unsubscribe from this group, send an email to: ap-gto-unsubscribe@... <*> Your use of Yahoo Groups is subject to: https://info.yahoo.com/legal/us/yahoo/utos/terms/ |
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Thomas Haugh
I am still struggling with aligning my new 1600. So, I purchased a RAPAS and installed. I aligned the mount using the instructions included and spent the first night just verifying Polaris' path. It followed the arc between the 2010 and 2020 reticle rings all night long.
I took that to mean the alignment was good enough to proceed with the GTO quick star drift alignment procedure. As the sky darkened the second night I verified Polaris was still in between the 2010 and 2020 reticle rings. Betelgeuse was at an hour angle of -45 minutes so I slewed to it. The star was in my 30mm eyepiece FOV. I centered the star and changed to a crosshair eyepiece. Following the instructions I centered the star on the crosshairs and re-calibrated. I then used the RA/DEC/REV menu to change the meridian to <1E>. The instructions say to press the RA/DEC/REV button to return to the objects menu. Pressing the button does not return to the objects menu. It stays on the RA/DEC/REV menu. I pressed Menu to return to the star information display and pressed GOTO again. The screen changed to the object menu and I selected Betelges and pressed GOTO. The mount swapped sides. Betelgeuse was not in the FOV of either eyepieces and indeed it was not in the FOV of my 7x50 finder. Looking at the scope, it was pointed in the close proximity to Bellatrix. Is it possible for Polaris to follow the arc so closely and for so long and still be that far off in alignment? I corrected the meridian and chose Betelges again, the mount swapped sides and the star was still visible in the crosshair eyepiece. I noticed that Betelgeuse and Bellatrix were adjacent in the star list so I tried the procedure several times to make sure I was selecting the correct star after changing the meridian delay. Any help will be greatly appreciated. Tom |
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Roland Christen
Your mount is most likely working correctly. You may have a severe orthogonal misalignment in your telescope.
It is best to start with the finderscope because it is relatively easy to adjust the orthogonality exactly just by using the thumbscrews. This way you can rule out any fault in the mount.
Check the orthogonality of the finder by choosing a known bright star near the zenith on either slightly East or slightly West side of the mount (do a GoTo).
1) Align the finder crosshair on the star
2) Do a meridian delay and pick up (do a GoTo) the same star on the other side.
3) Look to see where the finder is pointed. You can ignore any N-S offset, just concentrate on the East-West offset.
4) Now bring the star half way to the center of the crosshair by adjusting the finder screws. It is important that you go only half way.
5) Next bring the star all the way to the center of the crosshair using the East-West buttons on the keypad.
6) Press RA/Dec/Rev button and press 9=Recal
7) Now switch back the meridian delay to 0
8) Bring the star back up in the stars menu and do a GoTo to that same star.
9) The mount will flip sides back to the original side, and the star should appear close to the center of the crosshair East-West direction.
Now you have set the finderscope up to be fully orthogonal with the mount axes. Now you should be able to go to any star in the sky and be close. You should also be able to enter Betelgeuse near the meridian line and do a meridian delay, and pick it up close to center on both sides with your finderscope. Now that the finderscope is orthogonal to the mount, you can determine the non-orthogonality of your main scope by noting the difference where the finder is pointing versus where the main scope is pointing.
Rolando
-----Original Message-----
From: tom.haugh@... [ap-gto] To: ap-gto Sent: Wed, Jan 20, 2016 9:27 am Subject: [ap-gto] Re: Tracking difficulties I am still struggling with aligning my new 1600. So, I purchased a RAPAS and installed. I aligned the mount using the instructions included and spent the first night just verifying Polaris' path. It followed the arc between the 2010 and 2020 reticle rings all night long. I took that to mean the alignment was good enough to proceed with the GTO quick star drift alignment procedure. As the sky darkened the second night I verified Polaris was still in between the 2010 and 2020 reticle rings.
Betelgeuse was at an hour angle of -45 minutes so I slewed to it. The star was in my 30mm eyepiece FOV. I centered the star and changed to a crosshair eyepiece. Following the instructions I centered the star on the crosshairs and re-calibrated. I then used the RA/DEC/REV menu to change the meridian to <1E>.
The instructions say to press the RA/DEC/REV button to return to the obj
ects menu. Pressing the button does not return to the objects menu. It stays on the RA/DEC/REV menu.
I pressed Menu to return to the star information display and pressed GOTO again. The screen changed to the object menu and I selected Betelges and pressed GOTO. The mount swapped sides.
Betelgeuse was not in the FOV of either eyepieces and indeed it was not in the FOV of my 7x50 finder. Looking at the scope, it was pointed in the close proximity to Bellatrix.
Is it possible for Polaris to follow the arc so closely and for so long and still be that far off in alignment?
I corrected the meridian and chose Betelges again, the mount swapped sides and the star was still visible in the crosshair eyepiece.
I noticed that Betelgeuse and Bellatrix were adjacent in the star list so I tried the procedure several times to make s
ure I was selecting the correct star after changing the meridian delay.
Any help will be greatly appreciated.
Tom
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Thomas Haugh
Rolando,
Thank you for the info. I will try this the next clear night I get. Tom |
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Thomas Haugh
Rolando,
I have had two nights of clear skies to try your last set of instructions. Both nights using several stars and several attempts on each star had the same results. I would select a star within an hour of the meridian and GOTO. I then used the finder adjustments to center the star on the finder. Selected <1E> for the meridian delay. Selected the same star and GOTO. The star was never visible in the 7x50 finder and did not have enough 'adjustability' to get anywhere near half-way. Tom |
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