Wow!..
Wish my G11 had one of those RA Washers!
?
Derek
?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of John Kmetz
Sent: Sunday, September 29, 2019
9:57 PM
To: [email protected]
Subject: Re: [Losmandy_users_io]
Quite sticky mount
?
Franco,
To insert the washer, you will need to completely remove the RA lock knob while
being careful of the order of the washers and bearings underneath. Pics
attached.
Then you can slide out the upper RA assembly and shaft, then insert the clutch
washer and reassemble in reverse order.
Best Regards,
John
|
Luis,
Yes the purpose of the EQmod group program PECprep.exe is to analyze the Unguided PE data, by the method called FFT, and this tells the owner the exact frequencies present in the RA drive.? That program has a top menu selection for G11 and GM8 also...and many other mounts.? The program originally was designed for the Synta EQ6, but was nicely expanded by the authors to cover many popular mounts.
If the only large frequency is the worm period (on a G11 this is ~240 sec or 4 minutes.? On a GM8 that is 480 sec or 8 minutes), that is what is desired, and the PE value will be shown (in arcsec peak to peak and RMS).? You desire the PE to be under 2 arcsec RMS for a G11, or under 4 arcsec for a GM8.? The reason is that with the identical worm it should be double that for a GM8, because it's RA ring gear is half the diameter of the G11 ring gear.??
Some people have achieved ~1 arcsec RMS with their G11, or about 2 arcsec with their GM8.? It required a Losmandy precision brass worm, and usually (not always) a Losmandy OPW and a high grade ABEC5 or ABEC7 worm bearings, and a Belleville spring washer.??
The program can also tell you about frequencies unique to different drive gears. That way you can identify a problem mechanical component.? The nice part if the Losmandy system is that RA and DEC components are interchangeable, do you can run experiments to find the best parts for the RA drive.
Astronomy is very demanding on equipment...and people.? ?Early astronomers included Gauss, who invented the normal distribution to try and understand the varied data he was getting from other people.? Another was Albert Michelson, who used spectroscopy to (dis)prove the theory of the luminiferous ether, leading instead to the Lorentz equation and finally the theory of relativity.? It is an amazing miracle that our amateur equipment can be made so well that we can expect near perfect tracking from modestly expensive mounts.? We are all seeking perfection and it usually takes extra effort, or extra money, to get closer to it.
Very best, Michael
On Mon, Sep 30, 2019, 3:16 PM Luis Barneo < lbarneo@...> wrote: I had download your document some months ago. Your advise is unchecked? "Precision Pulse guide" and "Sync performs Additional Align". My telescope is in an horizontal position, the "Western Goto limit (from CWD) should be 0 or 90.00? What is the utility?of EQMOD software? To analize PEC?
El lun., 30 sept. 2019 a las 22:21, Michael Herman (< mherman346@...>) escribi¨®: Luis,
Here is a write-up I did for connecting the Gemini 1 to a PC.? There may be some info in there you can use.
The question of remote operation is coming up in this group nowadays.? However, I can't comment on the best ways to do that. Perhaps other owners can speak about how they are doing this. They may have a Gemini-2 and this newer version may make it easier.? I don't have one yet!
Very best,
Michael
On Mon, Sep 30, 2019, 10:58 AM Luis Barneo < lbarneo@...> wrote: Thanks Michael,
1.????? How does I save the model to my PC?
I usually Warm Restart with the hand controller deluxe and synchronized some
stars and not realized the aligment of these stars because I did it in a previous
session and the mount put the star almost in the center of the camera ST-402 (FOV of 8.9 x
13.4 arcmin). After, I connect TheSkyX Prof to find the stellar objects that
are not in the Gemini catalogs (asteroids, small stars,¡) and works with the
camera, focus, etc.
2.????? My small observatory is in the
mountain wihout internet. For the correct time I tried to connect the PC with a
GPS through Geminitelescope.net and gave the correct position, time and altitude.
I don¡¯t? know if these data collected by Geminitelescope.net is transmitted to the
mount that are a little difference of the data that appears when I warm ?with the hand controller (position, time), and
cause or not a disturbing to the mount . For this reason, I¡¯m afraid to control
the mount with the Geminitelescope.net.
El lun., 30 sept. 2019 a las 17:12, Michael Herman (< mherman346@...>) escribi¨®:
In theory, once you build your model, you should save it to your PC and not need to ever cold boot again.? Only do warm boot to load in the last model saved inside the Gemini1 SRAM chip.
I say save it to your PC because if your backup battery dies, the Gemini 1 will lose the settings. You can then upload the saved file after changing the battery.
Be sure to turn off settings in the Gemini.net applet that can affect the model. That is on the advanced panel, upper right checkbox for "Synch performs additional Align".? You don't want that!
Then, just Synch on a known star every time you do the wam boot. ?
And always park your system to a known position like CWD. ?
That's the theory. ?
In practice:
Some programs like Plate Solver programs do not know about the Gemini model and using both is reported to mess up pointing.? So if you are using plate solving, after the first Synch, ?try leaving the Gemini model at all zeros.? See if that fixes the issue. ?
Sometimes my model parameters are messed up. Perhaps I added a bad alignment point.? Or some other thing has happened.? In that case, I build a new model.
There is a chip in the Gemini1 made by Epson. It is called an RTC real time clock chip.? Some people have said that can lose or gain time and so you must reSynch your time.? There is a simple way to do that in ,... I think it's on the Telescope panel. ?
?
Making a good model:
The manual says: add 3 align points on one side of the meridian, then add 3 on the other side of the meridian.? That is, do 3 align points either East (or West) followed by 3 on the other side West (or East).
Have fun, and hope your system stays Aligned!
Best,? Michael
On Mon, Sep 30, 2019 at 2:25 AM Luis Barneo < lbarneo@...> wrote: I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
|
I had download your document some months ago. Your advise is unchecked? "Precision Pulse guide" and "Sync performs Additional Align". My telescope is in an horizontal position, the "Western Goto limit (from CWD) should be 0 or 90.00? What is the utility?of EQMOD software? To analize PEC?
El lun., 30 sept. 2019 a las 22:21, Michael Herman (< mherman346@...>) escribi¨®: Luis,
Here is a write-up I did for connecting the Gemini 1 to a PC.? There may be some info in there you can use.
The question of remote operation is coming up in this group nowadays.? However, I can't comment on the best ways to do that. Perhaps other owners can speak about how they are doing this. They may have a Gemini-2 and this newer version may make it easier.? I don't have one yet!
Very best,
Michael
On Mon, Sep 30, 2019, 10:58 AM Luis Barneo < lbarneo@...> wrote: Thanks Michael,
1.????? How does I save the model to my PC?
I usually Warm Restart with the hand controller deluxe and synchronized some
stars and not realized the aligment of these stars because I did it in a previous
session and the mount put the star almost in the center of the camera ST-402 (FOV of 8.9 x
13.4 arcmin). After, I connect TheSkyX Prof to find the stellar objects that
are not in the Gemini catalogs (asteroids, small stars,¡) and works with the
camera, focus, etc.
2.????? My small observatory is in the
mountain wihout internet. For the correct time I tried to connect the PC with a
GPS through Geminitelescope.net and gave the correct position, time and altitude.
I don¡¯t? know if these data collected by Geminitelescope.net is transmitted to the
mount that are a little difference of the data that appears when I warm ?with the hand controller (position, time), and
cause or not a disturbing to the mount . For this reason, I¡¯m afraid to control
the mount with the Geminitelescope.net.
El lun., 30 sept. 2019 a las 17:12, Michael Herman (< mherman346@...>) escribi¨®:
In theory, once you build your model, you should save it to your PC and not need to ever cold boot again.? Only do warm boot to load in the last model saved inside the Gemini1 SRAM chip.
I say save it to your PC because if your backup battery dies, the Gemini 1 will lose the settings. You can then upload the saved file after changing the battery.
Be sure to turn off settings in the Gemini.net applet that can affect the model. That is on the advanced panel, upper right checkbox for "Synch performs additional Align".? You don't want that!
Then, just Synch on a known star every time you do the wam boot. ?
And always park your system to a known position like CWD. ?
That's the theory. ?
In practice:
Some programs like Plate Solver programs do not know about the Gemini model and using both is reported to mess up pointing.? So if you are using plate solving, after the first Synch, ?try leaving the Gemini model at all zeros.? See if that fixes the issue. ?
Sometimes my model parameters are messed up. Perhaps I added a bad alignment point.? Or some other thing has happened.? In that case, I build a new model.
There is a chip in the Gemini1 made by Epson. It is called an RTC real time clock chip.? Some people have said that can lose or gain time and so you must reSynch your time.? There is a simple way to do that in ,... I think it's on the Telescope panel. ?
?
Making a good model:
The manual says: add 3 align points on one side of the meridian, then add 3 on the other side of the meridian.? That is, do 3 align points either East (or West) followed by 3 on the other side West (or East).
Have fun, and hope your system stays Aligned!
Best,? Michael
On Mon, Sep 30, 2019 at 2:25 AM Luis Barneo < lbarneo@...> wrote: I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
|
Sorry that nutty Google is playing new games with my documents.
I'll try and attach the file here again.
Hope it works. If not, send me an email and I'll send it?to you directly.
Best, Michael
On Mon, Sep 30, 2019, 1:38 PM Brian Valente < bvalente@...> wrote: michael this doc that begins with ""
it says I need to request access for it?
On Mon, Sep 30, 2019 at 1:27 PM Michael Herman < mherman346@...> wrote: Here are two documents.? One is about GM8 PE testing.? The other is about fixing the worm lateral containment.? Perhaps there are clues in that to help you solve your GM8 issue.? ?
All the best,
On Mon, Sep 30, 2019, 7:44 AM Michael Herman via Groups.Io <mherman346= [email protected]> wrote:
4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
--
Brian?
Brian Valente portfolio
|
Re: Upgrading from Half Hitch FTQ
Thank you everyone for super advice! I'll wait, work on selling my ftq, and consider the gm8.
|
correction, i think you attached the same pdf twice??
On Mon, Sep 30, 2019 at 1:29 PM Michael Herman < mherman346@...> wrote: The other document did not attach correctly...here it is.
Michael
Here are two documents.? One is about GM8 PE testing.? The other is about fixing the worm lateral containment.? Perhaps there are clues in that to help you solve your GM8 issue.? ?
All the best,
On Mon, Sep 30, 2019, 7:44 AM Michael Herman via Groups.Io <mherman346= [email protected]> wrote:
4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
-- Brian?
Brian Valente portfolio
|
michael this doc that begins with ""
it says I need to request access for it?
On Mon, Sep 30, 2019 at 1:27 PM Michael Herman < mherman346@...> wrote: Here are two documents.? One is about GM8 PE testing.? The other is about fixing the worm lateral containment.? Perhaps there are clues in that to help you solve your GM8 issue.? ?
All the best,
On Mon, Sep 30, 2019, 7:44 AM Michael Herman via Groups.Io <mherman346= [email protected]> wrote:
4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
-- Brian?
Brian Valente portfolio
|
The other document did not attach correctly...here it is.
Michael
Here are two documents.? One is about GM8 PE testing.? The other is about fixing the worm lateral containment.? Perhaps there are clues in that to help you solve your GM8 issue.? ?
All the best,
On Mon, Sep 30, 2019, 7:44 AM Michael Herman via Groups.Io <mherman346= [email protected]> wrote:
4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
|
Here are two documents.? One is about GM8 PE testing.? The other is about fixing the worm lateral containment.? Perhaps there are clues in that to help you solve your GM8 issue.? ?
All the best,
On Mon, Sep 30, 2019, 7:44 AM Michael Herman via Groups.Io <mherman346= [email protected]> wrote:
4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
|
Luis,
Here is a write-up I did for connecting the Gemini 1 to a PC.? There may be some info in there you can use.
The question of remote operation is coming up in this group nowadays.? However, I can't comment on the best ways to do that. Perhaps other owners can speak about how they are doing this. They may have a Gemini-2 and this newer version may make it easier.? I don't have one yet!
Very best,
Michael
On Mon, Sep 30, 2019, 10:58 AM Luis Barneo < lbarneo@...> wrote: Thanks Michael,
1.????? How does I save the model to my PC?
I usually Warm Restart with the hand controller deluxe and synchronized some
stars and not realized the aligment of these stars because I did it in a previous
session and the mount put the star almost in the center of the camera ST-402 (FOV of 8.9 x
13.4 arcmin). After, I connect TheSkyX Prof to find the stellar objects that
are not in the Gemini catalogs (asteroids, small stars,¡) and works with the
camera, focus, etc.
2.????? My small observatory is in the
mountain wihout internet. For the correct time I tried to connect the PC with a
GPS through Geminitelescope.net and gave the correct position, time and altitude.
I don¡¯t? know if these data collected by Geminitelescope.net is transmitted to the
mount that are a little difference of the data that appears when I warm ?with the hand controller (position, time), and
cause or not a disturbing to the mount . For this reason, I¡¯m afraid to control
the mount with the Geminitelescope.net.
El lun., 30 sept. 2019 a las 17:12, Michael Herman (< mherman346@...>) escribi¨®:
In theory, once you build your model, you should save it to your PC and not need to ever cold boot again.? Only do warm boot to load in the last model saved inside the Gemini1 SRAM chip.
I say save it to your PC because if your backup battery dies, the Gemini 1 will lose the settings. You can then upload the saved file after changing the battery.
Be sure to turn off settings in the Gemini.net applet that can affect the model. That is on the advanced panel, upper right checkbox for "Synch performs additional Align".? You don't want that!
Then, just Synch on a known star every time you do the wam boot. ?
And always park your system to a known position like CWD. ?
That's the theory. ?
In practice:
Some programs like Plate Solver programs do not know about the Gemini model and using both is reported to mess up pointing.? So if you are using plate solving, after the first Synch, ?try leaving the Gemini model at all zeros.? See if that fixes the issue. ?
Sometimes my model parameters are messed up. Perhaps I added a bad alignment point.? Or some other thing has happened.? In that case, I build a new model.
There is a chip in the Gemini1 made by Epson. It is called an RTC real time clock chip.? Some people have said that can lose or gain time and so you must reSynch your time.? There is a simple way to do that in ,... I think it's on the Telescope panel. ?
?
Making a good model:
The manual says: add 3 align points on one side of the meridian, then add 3 on the other side of the meridian.? That is, do 3 align points either East (or West) followed by 3 on the other side West (or East).
Have fun, and hope your system stays Aligned!
Best,? Michael
On Mon, Sep 30, 2019 at 2:25 AM Luis Barneo < lbarneo@...> wrote: I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
|
Thanks Michael,
1.????? How does I save the model to my PC?
I usually Warm Restart with the hand controller deluxe and synchronized some
stars and not realized the aligment of these stars because I did it in a previous
session and the mount put the star almost in the center of the camera ST-402 (FOV of 8.9 x
13.4 arcmin). After, I connect TheSkyX Prof to find the stellar objects that
are not in the Gemini catalogs (asteroids, small stars,¡) and works with the
camera, focus, etc.
2.????? My small observatory is in the
mountain wihout internet. For the correct time I tried to connect the PC with a
GPS through Geminitelescope.net and gave the correct position, time and altitude.
I don¡¯t? know if these data collected by Geminitelescope.net is transmitted to the
mount that are a little difference of the data that appears when I warm ?with the hand controller (position, time), and
cause or not a disturbing to the mount . For this reason, I¡¯m afraid to control
the mount with the Geminitelescope.net.
El lun., 30 sept. 2019 a las 17:12, Michael Herman (< mherman346@...>) escribi¨®:
In theory, once you build your model, you should save it to your PC and not need to ever cold boot again.? Only do warm boot to load in the last model saved inside the Gemini1 SRAM chip.
I say save it to your PC because if your backup battery dies, the Gemini 1 will lose the settings. You can then upload the saved file after changing the battery.
Be sure to turn off settings in the Gemini.net applet that can affect the model. That is on the advanced panel, upper right checkbox for "Synch performs additional Align".? You don't want that!
Then, just Synch on a known star every time you do the wam boot. ?
And always park your system to a known position like CWD. ?
That's the theory. ?
In practice:
Some programs like Plate Solver programs do not know about the Gemini model and using both is reported to mess up pointing.? So if you are using plate solving, after the first Synch, ?try leaving the Gemini model at all zeros.? See if that fixes the issue. ?
Sometimes my model parameters are messed up. Perhaps I added a bad alignment point.? Or some other thing has happened.? In that case, I build a new model.
There is a chip in the Gemini1 made by Epson. It is called an RTC real time clock chip.? Some people have said that can lose or gain time and so you must reSynch your time.? There is a simple way to do that in ,... I think it's on the Telescope panel. ?
?
Making a good model:
The manual says: add 3 align points on one side of the meridian, then add 3 on the other side of the meridian.? That is, do 3 align points either East (or West) followed by 3 on the other side West (or East).
Have fun, and hope your system stays Aligned!
Best,? Michael
On Mon, Sep 30, 2019 at 2:25 AM Luis Barneo < lbarneo@...> wrote: I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
|
I actually have the Belleville washers and new bearings mod.
The Oldham coupler is tight too.
No issue with RA since the motion does not reverse.
I got the backlash value from phd2. It automatically adjusts the compensation during guiding and ended at 4000ms which was my Max duration.?
I also directly measured it by moving the Dec at guide speed in photo mode with the hand controller. I placed? an Allen key in the Oldham coupler to easily observe when the shaft starts turning. When I reverse direction it takes at least 4 seconds to see a motion of the shaft.
|
In theory, once you build your model, you should save it to your PC and not need to ever cold boot again.? Only do warm boot to load in the last model saved inside the Gemini1 SRAM chip.
I say save it to your PC because if your backup battery dies, the Gemini 1 will lose the settings. You can then upload the saved file after changing the battery.
Be sure to turn off settings in the Gemini.net applet that can affect the model. That is on the advanced panel, upper right checkbox for "Synch performs additional Align".? You don't want that!
Then, just Synch on a known star every time you do the wam boot. ?
And always park your system to a known position like CWD. ?
That's the theory. ?
In practice:
Some programs like Plate Solver programs do not know about the Gemini model and using both is reported to mess up pointing.? So if you are using plate solving, after the first Synch, ?try leaving the Gemini model at all zeros.? See if that fixes the issue. ?
Sometimes my model parameters are messed up. Perhaps I added a bad alignment point.? Or some other thing has happened.? In that case, I build a new model.
There is a chip in the Gemini1 made by Epson. It is called an RTC real time clock chip.? Some people have said that can lose or gain time and so you must reSynch your time.? There is a simple way to do that in ,... I think it's on the Telescope panel. ?
?
Making a good model:
The manual says: add 3 align points on one side of the meridian, then add 3 on the other side of the meridian.? That is, do 3 align points either East (or West) followed by 3 on the other side West (or East).
Have fun, and hope your system stays Aligned!
Best,? Michael
On Mon, Sep 30, 2019 at 2:25 AM Luis Barneo < lbarneo@...> wrote: I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
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Re: Upgrading from Half Hitch FTQ
I have seen 492 G11 heads offered for as low as $750 recently. MA adapters are $100-125 used, but they don't come along often. If you can find one this Losmandy made adapter for the G9 will work for a Celestron field tripod. OnStep goto offers a inexpensive alternative to to Gemini II. See my blog for information.
I had a couple and let them go for $40. It would be fairly easy to machine. The center six holes can be omitted as they were for bolting it to a CG-5 tripod hub. The outer holes are located to use three of the six wedge fastening holes and two for the mount fastening holes. A 6" by .05" slice of aluminum rod runs about $20 on eBay. On early tripods the six wedge holes were threaded 5/16th". Later hubs have three threaded and three unthreaded. In the photo of the adapter mounted you can see a 5/16th" bolt under the hub used to fasten the adapter.
George
https://www.stmbluepillkits.com/
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Just curious how you determined your backlash was 4 seconds? if you are using PHD2 and have some example guidelogs to upload that would be great to see
Brian
Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
-- Brian?
Brian Valente portfolio
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4 secs seems very long.
I don't think the gearbox itself is a cause, but there is an Oldham coupler that links the gearbox to the worm. Sometimes the metal ends of that coupler can work loose. Usually it's easy to tighten the tiny setscrews that hold those coupler ends to their metal shafts using an Allen hex key wrench. I think the size is 0.050 inch (and is included in sets of American size hex key wrenches by Bondhus).
The movement of the worm toward the ring gear is easy, by design of the worm blocks. ?
The difficult element is the locking of the worm between the worm blocks, but it can be done. It is easier to add in a Belleville spring washer to the place behind the far bearing (far end of the worm, away from the coupler), that will always keep pressure on the bearing and the worm.
My GM8 has essentially no backlash in either axis with these adjustments.? I leave no gap between the worm and ring gear. ?
I am surprised your RA does not have the problem, but perhaps because RA is always driven at some rate (Sidereal or solar or lunar, perhaps). ?
Let me know if you need parts like the spring washers.? I'll send you a PDF about my GM8 results.
Best, Michael
Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
|
Hi,
I have a GM8 from 2006 (no upgrades) and I was looking into decreasing the DEC backlash.
From my understanding, there are 3 main sources of backlash:?
-Worm to gear not tight enough
-Worm loose between its blocks
-Gearbox.
The first two can be addressed with careful alignment.
What about the gearbox? From my tests it seems I need at least 4 seconds at guide speed to clear the backlash between input and output. Does that seems right?
Could this duration be decreased by doing the backlash compensation at higher speed? I don't see this option in PHD2, and I have read that it is better to leave the Gemini backlash compensation off when guiding.
|
I suppose that is not a true new topic about the Losmandy mount: how often is advisable to realize the modeling of the mount? Every time when I open in warm restart, only warm or could start? My mount is a Losmandy G11 Gemini1 level4 in a permanent pier.
Luis
|
Franco,
To insert the washer, you will need to completely remove the RA lock knob while being careful of the order of the washers and bearings underneath. Pics attached.
Then you can slide out the upper RA assembly and shaft, then insert the clutch washer and reassemble in reverse order.
Best Regards,
John
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Re: Quite sticky mount... and some ideas to balance loads...
Joe that¡¯s just what is needed empirical data?
--
Brendan
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Michael Herman
Luis Barneo