Thanks to everyone who replied for your input. I am moving fowward with the G11G with the goal of future proofing my setup for the forseeable future. I have the opportunity to pick up an unused G11G with the FHD, AKS, CKS, TKS, RAEXT, 2x 21lb counterweights, and 1x 9lb counterweight. This is pretty much every accessory available but is there anything else I should get in preperation for this mount? I've seen mixed reviews on the tripod feet for imaging, but are they important for visual? I also planned on powering this mount with the same pocket powerbox I used for my last mount, however the total output for the powerbox is 12V @ 10A and if I'm also powering a cooled astro cam, focuser, and dew heater, I'm not sure if the powerbox can handle the mount's power requirements or if I should be using a seperate power supply for the mount.?
-Vishal
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Re: G11 and 6¡± f/10 for imaging?
For reference, at 1500 frames per second you could hand hold the scope and get stable images :-)
--
Edward
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Re: "Nudge Mount Out of Safety Limit On Slew"?
FYI the Gemini Telescope.net driver user manual is available via the app itself, under the Help! menu
On Fri, Jul 2, 2021 at 11:05 AM Paul Kanevsky < yh@...> wrote: On Fri, Jul 2, 2021 at 02:01 PM, Chuck Gehrke wrote:
Just curious what this option/command does?
From the driver manual:
Normally if Gemini tracks into a safety limit the mount stops and must be manually backed away from the limit before you can GoTo your next target. Whilst this is a minor inconvenience for someone local to the mount, it is a major problem for automated operations. If this parameter is set it invokes a one second slew, at the currently configured slew rate, away from the safety limit. This feature is used by all ASCOM slew commands, including Alt/Az slews and equatorial slews. It is also used when a park command is issued that requires the mount to move from the current position. The driver waits for the one second slew to complete, and then issues the desired slew/park command, as usual.?
Regards,
? ?-Paul
-- Brian?
Brian Valente portfolio
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Re: "Nudge Mount Out of Safety Limit On Slew"?
On Fri, Jul 2, 2021 at 02:01 PM, Chuck Gehrke wrote:
Just curious what this option/command does?
From the driver manual:
Normally if Gemini tracks into a safety limit the mount stops and must be manually backed away from the limit before you can GoTo your next target. Whilst this is a minor inconvenience for someone local to the mount, it is a major problem for automated operations. If this parameter is set it invokes a one second slew, at the currently configured slew rate, away from the safety limit. This feature is used by all ASCOM slew commands, including Alt/Az slews and equatorial slews. It is also used when a park command is issued that requires the mount to move from the current position. The driver waits for the one second slew to complete, and then issues the desired slew/park command, as usual.?
Regards,
? ?-Paul
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Re: "Nudge Mount Out of Safety Limit On Slew"?
Just curious what this option/command does?
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Re: G11 and 6¡± f/10 for imaging?
Jim,
At 100 frames per second this should not be an issue. I've used a Skywatcher 150mm visually on a Losmandy G11 with classic drivetrain and it had no issues with vibration. Granted this is a 150mm f/8 scope so it is shorter but at over 300x any movement is easy to see with the mark I eyeball.?
--
Chip Louie Chief Daydreamer Imagination Hardware?
? ?Astropheric Weather Forecast - South Pasadena, CA?
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Re: Firecapture autoguide with Gemini 1 ?
Firecapture autoguider works just fine with Gemini-1.? You must of course have a working serial cable, ASCOM, and Gemini.net applet working.?
PHD2 does not care of any orientation of the autoguide camera, but FireCapture does care.
So, here is what you must do:
1. Rotate the planetary video camera so that the mount RA axis moving East West only moves the camera image left-right.? It need not be perfectly lined up but as good as you eyeball it.? ?Just use your hand controller and watch the planet motion ...should be left to right when you press East -West diamond buttons.?
2. In FireCapture, you must go to settings, and turn on the autoguide feature.? This should then have you select the mount, and you'll pick ASCOM and Gemini.net.? that will launch the Gemini.net applet.? You then set that to G (guide mode) [not C for Center mode or S for Slew mode] .
3. You must select a point in the planet...or perhaps it aitosejects the center of mass if the whole planet is in the frame.? I don't recall exactly!??
4. You may find that FireCapture gets the E-W horizontal or N-S vertical guide dire tions wrong.? In FC there is in the Settings for Autoguide check iced to reverse the E-W and N-S directions.? You may have to get those checked or unchecked until the autoguiding works.
5. Practice using a star.
Best of luck, Michael
I have a G11 with Gemini 1. Does anyone have any experience using Firecapture to autoguide on planets? Is this possible? Anything else needed?
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Firecapture autoguide with Gemini 1 ?
I have a G11 with Gemini 1. Does anyone have any experience using Firecapture to autoguide on planets? Is this possible? Anything else needed?
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Re: G11 and 6¡± f/10 for imaging?
>>>
That should be adequate for such short exposures. Not great, but adequate.
that was my thought. i'm probably a little more positive because it IS such short exposures it should be fine
On Thu, Jul 1, 2021 at 9:23 PM Joe Bergeron < joe@...> wrote: That should be adequate for such short exposures. Not great, but adequate.
Joe Bergeron
Fellow, International Association of Astronomical Artists
Author, The Endurian Universe novels
Author and illustrator, Cosmic Cat
-- Brian?
Brian Valente portfolio
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Re: G11 and 6¡± f/10 for imaging?
That should be adequate for such short exposures. Not great, but adequate.
Joe Bergeron
Fellow, International Association of Astronomical Artists
Author, The Endurian Universe novels
Author and illustrator, Cosmic Cat
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Hi Chuck
>>>What if you have a guide lodestar with 8.2 micron pixel size and an image camera with 3.8 micron pixel size? Would that effect or contribute a significant error?
It depends (isn't that like most answers in astronomy) ;)
If you have a specific example you're interested in, you can post the guide and image train image scales (or cameras and telescopes) and we can compare them
you can have a large pixel size on your guide camera but if its guiding well enough and/or the?image scale is close enough, it should be fine. The important measure is the RMS in arcsec/pix relative to the main imaging camera. Guiding on fractional pixel sizes has been around for a while and i think is underappreciated in terms of how effective it is.?
As a general rule of thumb i think image scale of 3:1 of guider image scale to imaging image scale is good. Beyond that the resolution of the guiding setup starts to be limited in terms of how accurate it can be.?
If the guiding RMS is less than 1 pixel for the imaging camera, I would consider that solid guiding.?
Brian
Your reply about image scale got me thinking. What if you have a guide lodestar with 8.2 micron pixel size and an image camera with 3.8 micron pixel size? Would that effect or contribute a significant error?
Chuck
On Thursday, July 1, 2021, 03:53:46 PM PDT, Brian Valente < bvalente@...> wrote:
>>>is this displayed in PHD Log viewer ?
yes, do just be clear i'm talking about the components of the guiding, not the?total guiding rms
If you have a perfect mount with 0 error, you are still limited by other conditions (seeing, wind, vibrations, hardware tilting)
i'm specifically talking about your notion of using PEMPro etc. to reduce the primary periodic error. in other words, what's the value of trying to implement PEC with your current setup
on your 3hr run, your PE for the primary is around 4.3" - FYI you'll notice your drift is much higher, but that's even easier to guide out
this PHD Log Viewer graph shows this:
That number is the calculated unguided PE
you can also choose to just analyze the guide data without backing out corrections:
here you can see your two peaks are both around 0.3" - in other words "residual error" i.e., what can't be guided out given your settings, configuration, hardware, etc.
The primary and 76 sec is prominent, but (here's the important part) they are both fractions of a pixel of your imaging camera.?
can you reduce those values using PEC? sure
will it make a difference? you're talking about error from PE going from maybe 1/3 of a pixel to maybe 1/4 or 1/8 of a pixel? you can decide if that's important to you ?
FYI I would give period length of 76.1s a try on PPEC and see how that goes. maybe drop your exposure time to 1-1.5sec Yeah I think I get what you are saying (not sure how you can tell the "wasn't guided out" error -- where does that come from ?
If I have a 1" guide error then that will also be a 1" error In the imager (since we assume the scopes are moving together - assuming no flex)
Since I am 2.2 a/s in the imager, that would mean 1"/2.2 = 0.45 pixels and for my 0.76 error it would be 0.76/2.2 = 0.34 pixels
Now somehow you managed to come up with the? 1/4" "wasn't guided out" error but my RMS in the log was 0.76" total, so now I am curious about how you backed out the other approx 0.5" - is this displayed in PHD Log viewer ?
-- Brian?
Brian Valente portfolio
-- Brian?
Brian Valente portfolio
|
Brian
Your reply about image scale got me thinking. What if you have a guide lodestar with 8.2 micron pixel size and an image camera with 3.8 micron pixel size? Would that effect or contribute a significant error?
Chuck
On Thursday, July 1, 2021, 03:53:46 PM PDT, Brian Valente <bvalente@...> wrote:
>>>is this displayed in PHD Log viewer ?
yes, do just be clear i'm talking about the components of the guiding, not the?total guiding rms
If you have a perfect mount with 0 error, you are still limited by other conditions (seeing, wind, vibrations, hardware tilting)
i'm specifically talking about your notion of using PEMPro etc. to reduce the primary periodic error. in other words, what's the value of trying to implement PEC with your current setup
on your 3hr run, your PE for the primary is around 4.3" - FYI you'll notice your drift is much higher, but that's even easier to guide out
this PHD Log Viewer graph shows this:
That number is the calculated unguided PE
you can also choose to just analyze the guide data without backing out corrections:
here you can see your two peaks are both around 0.3" - in other words "residual error" i.e., what can't be guided out given your settings, configuration, hardware, etc.
The primary and 76 sec is prominent, but (here's the important part) they are both fractions of a pixel of your imaging camera.?
can you reduce those values using PEC? sure
will it make a difference? you're talking about error from PE going from maybe 1/3 of a pixel to maybe 1/4 or 1/8 of a pixel? you can decide if that's important to you ?
FYI I would give period length of 76.1s a try on PPEC and see how that goes. maybe drop your exposure time to 1-1.5sec
Yeah I think I get what you are saying (not sure how you can tell the "wasn't guided out" error -- where does that come from ?
If I have a 1" guide error then that will also be a 1" error In the imager (since we assume the scopes are moving together - assuming no flex)
Since I am 2.2 a/s in the imager, that would mean 1"/2.2 = 0.45 pixels and for my 0.76 error it would be 0.76/2.2 = 0.34 pixels
Now somehow you managed to come up with the? 1/4" "wasn't guided out" error but my RMS in the log was 0.76" total, so now I am curious about how you backed out the other approx 0.5" - is this displayed in PHD Log viewer ?
-- Brian?
Brian Valente portfolio
|
On Thu, Jul 1, 2021 at 04:12 PM, Brian Valente wrote:
On Thu, Jul 1, 2021 at 04:11 PM, Nick Ambrose wrote:
Thank you so much for you help, it's awesome - maybe a topic for a future video so you can spend less time answering dumb questions from people like me :)
?
It's not a dumb question at all.?
I was just trying to offer some perspective here on how much you want to be fiddling with things (which we are all inclined to do) vs. how much better are your images going to be as a result
Completely agree. In the end its all about images and frankly I am pretty happy with the test images I took the other day. I'm about to embark on collecting a lot of data on a single object and I'd hate to go do that and then find out that I had something not set up well and the data is not as good as it reasonably could be On the other hand as you say, there is no advantage sitting here improving a graph all day and getting distracted from why we do this in the first place -- which is either to make nice images or look at cool stuff in the sky I do appreciate the responses !
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On Thu, Jul 1, 2021 at 04:11 PM, Brian Valente wrote:
Nick i previously posted a response to this?
The reason I ask is what I see in PHD Log viewer is, which says 0.76", so in my mind I now take 0.76/2.2as/px = 0.38pixels on the imaging camera, which is great
I do see 0.5"/sec RA drift and 0.12" DEC in the drift tab but I didn't think I got to minus those off the total RMS
So I am just curious where the 0.25" comes from since I am already excluding dither variations here
?
?
?
--
Brian?
?
?
?
Brian Valente
portfolio
Apologies. I think we were posting at the same time! I saw your response after I hit send
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On Thu, Jul 1, 2021 at 04:11 PM, Nick Ambrose wrote:
Thank you so much for you help, it's awesome - maybe a topic for a future video so you can spend less time answering dumb questions from people like me :)
?
It's not a dumb question at all.? I was just trying to offer some perspective here on how much you want to be fiddling with things (which we are all inclined to do) vs. how much better are your images going to be as a result
|
Nick i previously posted a response to this?
The reason I ask is what I see in PHD Log viewer is, which says 0.76", so in my mind I now take 0.76/2.2as/px = 0.38pixels on the imaging camera, which is great
I do see 0.5"/sec RA drift and 0.12" DEC in the drift tab but I didn't think I got to minus those off the total RMS
So I am just curious where the 0.25" comes from since I am already excluding dither variations here
-- Brian?
Brian Valente portfolio
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Re: G11 and 6¡± f/10 for imaging?
Very unlikely.? A 5' scope will act as a sail in the wind.
------------------------
Jim W
Phoenix, AZ. USA
Losmandy GM811G, NINA 1.11, ASI2600MC Pro, Sky-Watcher Scopes
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On Thu, Jul 1, 2021 at 03:53 PM, Brian Valente wrote:
>>> is this displayed in PHD Log viewer ?
?
yes, do just be clear i'm talking about the components of the guiding, not the?total guiding rms
?
If you have a perfect mount with 0 error, you are still limited by other conditions (seeing, wind, vibrations, hardware tilting)
?
i'm specifically talking about your notion of using PEMPro etc. to reduce the primary periodic error. in other words, what's the value of trying to implement PEC with your current setup
?
on your 3hr run, your PE for the primary is around 4.3" - FYI you'll notice your drift is much higher, but that's even easier to guide out
?
this PHD Log Viewer graph shows this:
?
?
That number is the calculated unguided PE
?
you can also choose to just analyze the guide data without backing out corrections:
?
?
here you can see your two peaks are both around 0.3" - in other words "residual error" i.e., what can't be guided out given your settings, configuration, hardware, etc.
?
The primary and 76 sec is prominent, but (here's the important part) they are both fractions of a pixel of your imaging camera.?
?
can you reduce those values using PEC? sure
?
will it make a difference? you're talking about error from PE going from maybe 1/3 of a pixel to maybe 1/4 or 1/8 of a pixel? you can decide if that's important to you
?
FYI I would give period length of 76.1s a try on PPEC and see how that goes. maybe drop your exposure time to 1-1.5sec
Yeah I think I get what you are saying (not sure how you can tell the "wasn't guided out" error -- where does that come from ?
If I have a 1" guide error then that will also be a 1" error In the imager (since we assume the scopes are moving together - assuming no flex)
Since I am 2.2 a/s in the imager, that would mean 1"/2.2 = 0.45 pixels and for my 0.76 error it would be 0.76/2.2 = 0.34 pixels
Now somehow you managed to come up with the? 1/4" "wasn't guided out" error but my RMS in the log was 0.76" total, so now I am curious about how you backed out the other approx 0.5" - is this displayed in PHD Log viewer ?
?
?
?
--
Brian?
?
?
?
Brian Valente
portfolio
Thank you! This is fascinating. Obiously I have a lot to learn here! I'm going to look at this myself. I will definitely try the 76.1 configuration and see if that helps! Thank you so much for you help, it's awesome - maybe a topic for a future video so you can spend less time answering dumb questions from people like me :)
|
The reason I ask is what I see in PHD Log viewer is, which says 0.76", so in my mind I now take 0.76/2.2as/px = 0.38pixels on the imaging camera, which is great
I do see 0.5"/sec RA drift and 0.12" DEC in the drift tab but I didn't think I got to minus those off the total RMS
So I am just curious where the 0.25" comes from since I am already excluding dither variations here
|
>>>
is this displayed in PHD Log viewer ?
yes, do just be clear i'm talking about the components of the guiding, not the?total guiding rms
If you have a perfect mount with 0 error, you are still limited by other conditions (seeing, wind, vibrations, hardware tilting)
i'm specifically talking about your notion of using PEMPro etc. to reduce the primary periodic error. in other words, what's the value of trying to implement PEC with your current setup
on your 3hr run, your PE for the primary is around 4.3" - FYI you'll notice your drift is much higher, but that's even easier to guide out
this PHD Log Viewer graph shows this:
That number is the calculated unguided PE
you can also choose to just analyze the guide data without backing out corrections:
here you can see your two peaks are both around 0.3" - in other words "residual error" i.e., what can't be guided out given your settings, configuration, hardware, etc.
The primary and 76 sec is prominent, but (here's the important part) they are both fractions of a pixel of your imaging camera.?
can you reduce those values using PEC? sure
will it make a difference? you're talking about error from PE going from maybe 1/3 of a pixel to maybe 1/4 or 1/8 of a pixel? you can decide if that's important to you ?
FYI I would give period length of 76.1s a try on PPEC and see how that goes. maybe drop your exposure time to 1-1.5sec
Yeah I think I get what you are saying (not sure how you can tell the "wasn't guided out" error -- where does that come from ?
If I have a 1" guide error then that will also be a 1" error In the imager (since we assume the scopes are moving together - assuming no flex)
Since I am 2.2 a/s in the imager, that would mean 1"/2.2 = 0.45 pixels and for my 0.76 error it would be 0.76/2.2 = 0.34 pixels
Now somehow you managed to come up with the? 1/4" "wasn't guided out" error but my RMS in the log was 0.76" total, so now I am curious about how you backed out the other approx 0.5" - is this displayed in PHD Log viewer ?
-- Brian?
Brian Valente portfolio
|
Edward Plumer
Paul Kanevsky
Chuck Gehrke
Chip Louie
Michael Herman