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From CWD and line-of-sight to Polaris, I turn on my Gemini 2 controller and do a simple goto to Mars. Planetary tracking to keep the planet roughly centered doesn't work very well. It's specifically frustrating when I switch from wide-field - an F6 or F7- to narrow-field to better image the planet. I'm using a C8 with a 2.5x barlow and a large pixel (4.67um) camera for capturing.?
I've tried Shaprcap polar alignment routine but as soon as I change out my reducer for the barlow, I'm back to square one in aligning with the planet.
Any help to resolve this dilemma would be appreciated.
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Glenn,
I suggest:
1. Just use sidereal tracking.
2. Planets, sun, and moon are not stars and they do move.? So you want autoguiding.? It is free and built into Fire capture!
3. Download and install them latest FireCapture.? Set up your video imaging camera.? You do not need a separate autoguide camera.?
4. From Fire capture, look for the bottom icons to set up it's Telescope mount ASCOm connection.? Choose Gemini.net. use that to connect to your Gemini unit.
5. Now you must rotate your video camera so it's X axis is aligned with your RA axis movement.? Then set up the FireCapture autoguider panel. You may have to use the Invert RA or Invert DEC setting checkboxes. Test this out on Mars earlier or Jupiter or Saturn perhaps.
6. You also want to check the Exposure settings:? A) capture in SER B) capture in RAW?format by turning off DeBayer during capture C) Turn on Autoguide only after hand centering the planet in your camera frame.?? D) Check the box for High Speed capture
When capturing use the Histogram to watch the 3 color histograms (if you are using a color video camera)? There are separate spiders in the Capture setting (gear icon under the exposure panel) for Red and Blue.? Try to get the exposures of the colors to be nearly equal.? On Mars you may not find much blue as it is dominated by Red of course.?
7.? Have fun and best of luck.
Michael
From CWD and line-of-sight to Polaris, I turn on my Gemini 2 controller and do a simple goto to Mars. Planetary tracking to keep the planet roughly centered doesn't work very well. It's specifically frustrating when I switch from wide-field - an F6 or F7- to narrow-field to better image the planet. I'm using a C8 with a 2.5x barlow and a large pixel (4.67um) camera for capturing.?
I've tried Shaprcap polar alignment routine but as soon as I change out my reducer for the barlow, I'm back to square one in aligning with the planet.
Any help to resolve this dilemma would be appreciated.
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I know it's not really standard and somehow controversial but I've changed the gearboxes on my mount to McLennan 25:1 then 50:1. It made a big difference in tracking for my planetary imaging. The mount is a lot smoother with corrections and increased torque at the worm in sidereal. I can track Mars in a 400 pixel square ROI at 8m FL quite comfortably for 3 min at a? time without any issues. Regardless long FL imaging is taxing on any mount. You need to go back to basic mechanics, makes sure the worm tracks are clean, the grease the right type with no contamination and then a good polar alignment and balance are critical.
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Michael,
Thanks for your reply. I have FireCapture installed. You mentioned hand-centering the planet before launching Autoguide in FireCapture. But that's been my problem. Doing a goto in Gemini to Mars after starting it from CWD, I can't even see Mars in FireCapture, let alone center it. The mount looks like it's right on the planet just from line-of-sight, but my image train, with a 2.5x barlow, is just too narrow a view to try to slew the mount to frame the planet. I end up spending an hour or more with no luck and I just give up.
That's what I need to do. Any thoughts on that?
Thanks,
Glenn
?
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Glen,
Your problem is a common one.?
The image chip is quite small (regardless of the large number of pixels, the chips are still small....and therefore inexpensive).? Even if the planet is centered in your finder scope it may be just off the small chip area.??
So I do this:
I leave the video camera connected by cable, but carefully remove the video camera from the optical train. Don't let the camera fall to the ground.? ?I then insert a 1.25 inch diagonal and wide angle eyepiece.? I don't expect the panet to be in focus, I only need to see where the planet is in the wide field center the planet in the eyepiece. Then I reinsert the video camera and....voila: the planet is in the video image.??
Sometimes especially for an SCT, the focus can be so far out, you have the dark central obstruction in focus.? You can use the moon to get the focus settings then go back to the planet.??
When on Jupiter, I push the gain way up, the exposure way up and use a visible moon of Jupiter with a Bahtinov mask to set my focus.? Then go back to Jupiter with lower settings.??
Anyway, focus the video image, center it, but.. not yet don't start the Autoguider in FireCapture.?
Also rotate the video camera so the rings of Saturn or equatorial bands of Jupiter are horizontal.? This aids in later de-rotating the planet frames in the WinJuPos program.? I guess you could also try to get the polar cap of Mars at the bottom of the image to de-rotate that planet also.? ??
Then...recenter the planet and start the Autoguider in FireCapture.?
If the Autoguider then quickly moves the planet left or right out of the frame, you must check (or uncheck) the RA reverse setting in FireCapture autoguider. Likewise if the image moves quickly out of frame up or down it is the DEC checkbox reverse that must be changed.?
This is an experimental hobby. Try some things ...you really can't harm anything.? ?Keep notes about your optical setup and Firecapture settings so you can find the optimal settings for your system.
Have fun, and enjoy the journey!
Michael
Michael,
Thanks for your reply. I have FireCapture installed. You mentioned hand-centering the planet before launching Autoguide in FireCapture. But that's been my problem. Doing a goto in Gemini to Mars after starting it from CWD, I can't even see Mars in FireCapture, let alone center it. The mount looks like it's right on the planet just from line-of-sight, but my image train, with a 2.5x barlow, is just too narrow a view to try to slew the mount to frame the planet. I end up spending an hour or more with no luck and I just give up.
That's what I need to do. Any thoughts on that?
Thanks,
Glenn
?
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I use a Vixen flip mirror in the optical train of my refractor to visually confirm placement of what I'm locating to image. Perhaps that would ease the struggle?
Jamey
Glen,
Your problem is a common one.?
The image chip is quite small (regardless of the large number of pixels, the chips are still small....and therefore inexpensive).? Even if the planet is centered in your finder scope it may be just off the small chip area.??
So I do this:
I leave the video camera connected by cable, but carefully remove the video camera from the optical train. Don't let the camera fall to the ground.? ?I then insert a 1.25 inch diagonal and wide angle eyepiece.? I don't expect the panet to be in focus, I only need to see where the planet is in the wide field center the planet in the eyepiece. Then I reinsert the video camera and....voila: the planet is in the video image.??
Sometimes especially for an SCT, the focus can be so far out, you have the dark central obstruction in focus.? You can use the moon to get the focus settings then go back to the planet.??
When on Jupiter, I push the gain way up, the exposure way up and use a visible moon of Jupiter with a Bahtinov mask to set my focus.? Then go back to Jupiter with lower settings.??
Anyway, focus the video image, center it, but.. not yet don't start the Autoguider in FireCapture.?
Also rotate the video camera so the rings of Saturn or equatorial bands of Jupiter are horizontal.? This aids in later de-rotating the planet frames in the WinJuPos program.? I guess you could also try to get the polar cap of Mars at the bottom of the image to de-rotate that planet also.? ??
Then...recenter the planet and start the Autoguider in FireCapture.?
If the Autoguider then quickly moves the planet left or right out of the frame, you must check (or uncheck) the RA reverse setting in FireCapture autoguider. Likewise if the image moves quickly out of frame up or down it is the DEC checkbox reverse that must be changed.?
This is an experimental hobby. Try some things ...you really can't harm anything.? ?Keep notes about your optical setup and Firecapture settings so you can find the optimal settings for your system.
Have fun, and enjoy the journey!
Michael
Michael,
Thanks for your reply. I have FireCapture installed. You mentioned hand-centering the planet before launching Autoguide in FireCapture. But that's been my problem. Doing a goto in Gemini to Mars after starting it from CWD, I can't even see Mars in FireCapture, let alone center it. The mount looks like it's right on the planet just from line-of-sight, but my image train, with a 2.5x barlow, is just too narrow a view to try to slew the mount to frame the planet. I end up spending an hour or more with no luck and I just give up.
That's what I need to do. Any thoughts on that?
Thanks,
Glenn
?
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Yes! A flip mirror is an excellent way to keep a visual eyepiece alternative to the video camera.? Great that you mention this approach.
But some optical systems won't allow it.
One of them is the Celestron Edge HD family. My C14 EdgeHD requires a 5.75 inch focal plane distance from the back flange surface, and none of my flip mirrors will fit that and a filter wheel or ADC.? But for refractors, or other conventional SCT designs a flip mirror would be useful.??
Stay well, Michael
I use a Vixen flip mirror in the optical train of my refractor to visually confirm placement of what I'm locating to image. Perhaps that would ease the struggle?
Jamey
Glen,
Your problem is a common one.?
The image chip is quite small (regardless of the large number of pixels, the chips are still small....and therefore inexpensive).? Even if the planet is centered in your finder scope it may be just off the small chip area.??
So I do this:
I leave the video camera connected by cable, but carefully remove the video camera from the optical train. Don't let the camera fall to the ground.? ?I then insert a 1.25 inch diagonal and wide angle eyepiece.? I don't expect the panet to be in focus, I only need to see where the planet is in the wide field center the planet in the eyepiece. Then I reinsert the video camera and....voila: the planet is in the video image.??
Sometimes especially for an SCT, the focus can be so far out, you have the dark central obstruction in focus.? You can use the moon to get the focus settings then go back to the planet.??
When on Jupiter, I push the gain way up, the exposure way up and use a visible moon of Jupiter with a Bahtinov mask to set my focus.? Then go back to Jupiter with lower settings.??
Anyway, focus the video image, center it, but.. not yet don't start the Autoguider in FireCapture.?
Also rotate the video camera so the rings of Saturn or equatorial bands of Jupiter are horizontal.? This aids in later de-rotating the planet frames in the WinJuPos program.? I guess you could also try to get the polar cap of Mars at the bottom of the image to de-rotate that planet also.? ??
Then...recenter the planet and start the Autoguider in FireCapture.?
If the Autoguider then quickly moves the planet left or right out of the frame, you must check (or uncheck) the RA reverse setting in FireCapture autoguider. Likewise if the image moves quickly out of frame up or down it is the DEC checkbox reverse that must be changed.?
This is an experimental hobby. Try some things ...you really can't harm anything.? ?Keep notes about your optical setup and Firecapture settings so you can find the optimal settings for your system.
Have fun, and enjoy the journey!
Michael
Michael,
Thanks for your reply. I have FireCapture installed. You mentioned hand-centering the planet before launching Autoguide in FireCapture. But that's been my problem. Doing a goto in Gemini to Mars after starting it from CWD, I can't even see Mars in FireCapture, let alone center it. The mount looks like it's right on the planet just from line-of-sight, but my image train, with a 2.5x barlow, is just too narrow a view to try to slew the mount to frame the planet. I end up spending an hour or more with no luck and I just give up.
That's what I need to do. Any thoughts on that?
Thanks,
Glenn
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The ideas I've received here are great. Another thought that has come to mind is to just use a decent finderscope aligned with the main scope.?
Thanks all,
Glenn
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Michael Herman
