Re: Beginner: how to adjust G11 altitude bolts?
Dear MB,
Losmandy has replacement knobs that go in place of the Allen head screws and are much easier to work with than the original altitude locks.
I have found these really help with the final fine tuning where you may have to loosen and tighten each side several times. Since you don't need a wrench anymore, it simplifies tweaking in the dark. You may find a progressive side to side tightening works better than just one twist on each, and then do a recheck after every adjustment. Other brand mounts and wedges have a similar routine.
Best Regards.
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Hi Kenn
usually one side of the axis is "looser" than the other when balancing. for DEC you can also rotate the RA axis past parallel to the ground to loosen up the axis even more
regarding improved guiding, i think that's just coincidence. There are so many things that go into a good night of guiding it would be unlikely that slight rebalancing (it sounds like you do a good job on balancing in general) would make much of an improvement.?
happy to review your before/after guidelogs if that's the case
Brian
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Re: Beginner: how to adjust G11 altitude bolts?
Hi England
you have some good advice here, i'd like to offer a few more tips
1. yes you should loosen both, but just enough to move the alt adjustment. you don't want to loosen them completely
2. If you want accurate polar alignment, it's usually an iterative process of tightening and moving, tightening some more and moving.?
3. i tighten them as tight as I can get. If you try, you will still be able to move them, given the force you can apply from the adjustment knob, so don't worry it you can still move it.
4. why are there two? two is better than one! more secure
also just making sure you are loosening the alt adjustment bolts (top ones on each side) and not the two bolts beneath them that hold the RA axis together
Brian
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Re: configuring ethernet/microrouter for gemini
Count me in for a zoom meeting! Mearl In VA
On Thu, Apr 23, 2020, 1:27 PM Brian Valente < bvalente@...> wrote: there's been an ongoing discussion about how to hook up your gemini via ethernet/wifi
i'm thinking of doing a zoom meeting or possibly facebook live this weekend to go through this setup. (we are eventually going to do a tutorial video on this, so think of it as a dry run to see what questions come up)
maybe sunday as several people are getting their routers on saturday
what interest/preference is there for something like this?
(the discussion is here if you are interested)
I recommend and use this particular microRouter:? ?)
you will need at least 2 ethernet cables (cat5/6)
-- Brian?
Brian Valente portfolio
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Re: The First Mars Helicopter Will Fly with Maxon Motors
On Thu, Apr 23, 2020 at 06:19 PM, Brendan Smith wrote:
maxon motors are around $300 AUD alone...!?? I would also need a machined housing.? Spent the last 2 weeks going over motor specs from many mfgrs...it's a minefield!
Ouch :-/ Good luck in your endeavor ;-) Cheers, Carl
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Hi Ken,
I have experienced similar balancing issues. If you achieve perfect balance the scope should stay still in absolutely any position you set it.
For me the key to achieve that is to not only level DEC horizontally (moving scope, at 0¡ã relative to ground, forward or backward) but also vertically (rotating scope, at 90¡ã relative to ground).
This video explains it much better than I did (relevant part from 5:30 onward):?
Edit: I should add that if you don't have a spring loaded worm gears, then you do not wan't perfect balance, you want slight east heavy balance.
But IMO the best is still to get perfect balance and then add the "RA worm string bias trick":?
Cheers,
Carl
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Re: Beginner: how to adjust G11 altitude bolts?
Generally I found that the only one I need to slacken is the upper Allen bolt that runs in the machined arc (unless the lower one is tightened up really hard). ? If you have backlash when adjusting the hand wheel then you need to tighten up the collar that increases the load on the thrust bearing which bears on the base of the knob there was a discussion of this recently and the following two post by Chip Louie are relevant: ? /g/Losmandy_users/message/59847 ? and ? /g/Losmandy_users/message/59878 ? This website in Italian may also be helpful: ?
? If the altitude mechanism seizes when you try to turn the knob something is rather amiss. ? You should snug both set of Allen bolts after adjustment. ? As you¡¯re in the UK, if you can¡¯t sort it out, I¡¯m happy to look at the problem for you either via webcam (maybe Skype) or in person after the lockdown if you can bring the mount to me. ? David ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Paul Homer
Sent: 24 April 2020 10:09
To: [email protected]
Subject: Re: [Losmandy_users_io] Beginner: how to adjust G11 altitude bolts?? England, I would loosed the bolts slightly while polar aligning and then tighten them once aligned - more than finger tight. ?
? Hello from England.?I'm a newcomer to Losmandy products. I cannot fathom the G11's 2 allen bolt altitude adjustment. Please can someone answer: - The hand knob only declines the mount head, and semi-seizes when trying to incline it.
- Common sense say both altitude bolts should be slackened to enable adjustment. Should they only be done up finger tight once set?
- Mechanically, why are there?two?locking bolts?
Thanks in advance. ?
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Re: Beginner: how to adjust G11 altitude bolts?
England,
I would loosed the bolts slightly while polar aligning and then tighten them once aligned - more than finger tight.
toggle quoted message
Show quoted text
Hello from England.?I'm a newcomer to Losmandy products. I cannot fathom the G11's 2 allen bolt altitude adjustment. Please can someone answer:
- The hand knob only declines the mount head, and semi-seizes when trying to incline it.
- Common sense say both altitude bolts should be slackened to enable adjustment. Should they only be done up finger tight once set?
- Mechanically, why are there?two?locking bolts?
Thanks in advance.
|
Previously when I balanced my scope/mount I start with the DEC. I set the RA to be parallel to the ground and I usually balanced the DEC so when the front of the scope is pointing North the scope stays parallel to the ground also. I can touch the scope and no matter how much pressure I place the scope it will stay in that position-just a little eye piece/camera heavy.
Today, after I changed scopes and balanced DEC, I also moved the scope to point South with some interesting results. The front of the scope moved up about 5/6 inches; interesting. I then moved the scope so it pointed North and it stayed level; interesting.
I then pointed the scope straight up and the front of the scope moved North. OK, I decided to balance the scope so it would move, slowly, back to almost straight up. I¡¯ve never had PHD2 track better using a FLT132 925mm scope as the guider. I balanced RA as I usually do, no changing the balance routine method with RA
Any comments would be welcome.
Kenn
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Beginner: how to adjust G11 altitude bolts?
Hello from England.?I'm a newcomer to Losmandy products. I cannot fathom the G11's 2 allen bolt altitude adjustment. Please can someone answer:
- The hand knob only declines the mount head, and semi-seizes when trying to incline it.
- Common sense say both altitude bolts should be slackened to enable adjustment. Should they only be done up finger tight once set?
- Mechanically, why are there?two?locking bolts?
Thanks in advance.
|
Re: The First Mars Helicopter Will Fly with Maxon Motors
Thanks Carl but maxon motors are around $300 AUD alone...!?? I would also need a machined housing.? Spent the last 2 weeks going over motor specs from many mfgrs...it's a minefield!
--
Brendan
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PHD2 gives me an odd graph with my GM811G HD set up.
But what tells it all is my imaging results. As long as I'm getting great guiding and tracking (and I am),
I don't really care what sort of hash PHD2 shows.
Don't get hung up on PHD2 graphs. They can vary like the weather.
Pay attention to your results. That's the Proof that's in the Pudding.
PHD2 is to latch onto a single star, then follow it. And it can do that well enough for Photographic results.
Especially with your new mount. Mine does.
--
SonnyE
(I suggest viewed in full screen)
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Steve
also FYI the spring-loaded worms do not register well with the backlash measurement in PHD. If you review your actual guiding results you'll see they are quite good (i'm assuming the 1.1 arcsec/pixel is from guiding). you can't get that with a backlash of nearly 34 seconds.
Bruce and Andy and I have discussed this ad nauseam?
If PHD only worked with losmandy mounts?i think they would remove that warning, but there are many other types of mounts for which this is a helpful bit of information.?
On Thu, Apr 23, 2020 at 12:51 PM Steve Elmore via <gizmo_s67= [email protected]> wrote: I received my new GM811G and finally got out under the stars to start learning the mount and Gemini 2 system.? Before I got started, I noticed some movement in the DEC axis.? With minimum effort, i can wiggle the saddle, i.e. DEC axis.? I am working with PHD2 and got some messages about the DEC axis, don't remember exactly.? I ran the guiding assistant and I thought the numbers looked good, except for the DEC Backlash was highlighted.? Here are some of the values:
RA Peak? 0.44px(6.73arc-sec)
DEC Peak? 0.37px(5.61arc-sec)
RA Peak to Peak0.47px(7.13arc-sec)
RA Drift Rate-0.09px/min(-1.41arc-sec/min)
RA Max Drift Rate0.04px/sec(0.67arc-sec/sec)
Drift-limiting exposure2.4s
DEC Drift Rate -0.01px/min(-0.21arc-sec/min
DEC Backlash >=34970 +/-99ms(247.1 +/-0.7a....
Polar Alignment Error 0.9 arc-min
High-frequency Star Motion
RA, RMS 0.05px(0.80 arc-sec)
DEC, RMS 0.05px(0.75arc-sec)
Total, RMS? 0.07px(1.10arc-sec)
Should I address the looseness in the DEC axis?? I've watched the video how to adjust the spring-loaded worm gear.? Would that be the way to eliminate the looseness?
Thanks for any help, Steve
-- Brian?
Brian Valente portfolio
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Hi Steve
i would not worry about it right now - chances are it's some movement from the spring-loaded worm
your best bet for PHD is to do a baseline guiding by following these steps here:
that will give you (and the folks who support PHD including me) a great foundation for performance and your mount's characteristics
Hey Steve,
From my experience and thanks to Brian's help I have learned that you shouldn't worry about DEC backlash measurement.
It is just a thing PHD2 can't handle with a spring loaded version. Besides latest version of PHD2 will measure and compensate it while guiding, the more you guide the better it gets.
Also the better your polar alignment and seeing conditions are, the less it has to correct DEC.
Your RMS error looks good!
Cheers,
Carl
-- Brian?
Brian Valente portfolio
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Hey Steve,
From my experience and thanks to Brian's help I have learned that you shouldn't worry about DEC backlash measurement.
It is just a thing PHD2 can't handle with a spring loaded version. Besides latest version of PHD2 will measure and compensate it while guiding, the more you guide the better it gets.
Also the better your polar alignment and seeing conditions are, the less it has to correct DEC.
Your RMS error looks good!
Cheers,
Carl
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I received my new GM811G and finally got out under the stars to start learning the mount and Gemini 2 system.? Before I got started, I noticed some movement in the DEC axis.? With minimum effort, i can wiggle the saddle, i.e. DEC axis.? I am working with PHD2 and got some messages about the DEC axis, don't remember exactly.? I ran the guiding assistant and I thought the numbers looked good, except for the DEC Backlash was highlighted.? Here are some of the values:
RA Peak? 0.44px(6.73arc-sec)
DEC Peak? 0.37px(5.61arc-sec)
RA Peak to Peak0.47px(7.13arc-sec)
RA Drift Rate-0.09px/min(-1.41arc-sec/min)
RA Max Drift Rate0.04px/sec(0.67arc-sec/sec)
Drift-limiting exposure2.4s
DEC Drift Rate -0.01px/min(-0.21arc-sec/min
DEC Backlash >=34970 +/-99ms(247.1 +/-0.7a....
Polar Alignment Error 0.9 arc-min
High-frequency Star Motion
RA, RMS 0.05px(0.80 arc-sec)
DEC, RMS 0.05px(0.75arc-sec)
Total, RMS? 0.07px(1.10arc-sec)
Should I address the looseness in the DEC axis?? I've watched the video how to adjust the spring-loaded worm gear.? Would that be the way to eliminate the looseness?
Thanks for any help, Steve
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Re: unguided imaging on the G11 - wrapping up the tests
On Tue, Apr 21, 2020 at 07:50 PM, <esmdavis1@...> wrote:
Have you measured your PA?
I believe from memory, having read something on PemPro forum a few weeks ago, that Brian has a sub 1 arc sec PA error using PEC (with Gemini obviously) and below 3" without PEC. But I believe that is with latest spring loaded worm gear G11. I think that with proper seasonal worm gear mesh tuning you should be able to reach 5-7", which should allow unguided photography well over 50mm focal length. Now if you are using a photo lens, from my experience, you'll get additional optical aberrations which might make it look like mechanical issue, were in fact it is an optical issue. That is especially true for blue/green channels.
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Re: The First Mars Helicopter Will Fly with Maxon Motors
On Wed, Apr 15, 2020 at 05:35 PM, Brendan Smith wrote:
sadly even the shipping to down under is a stretch! ?
Huh, I live in Switzerland, I might be able to help with lowering shipping cost...
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configuring ethernet/microrouter for gemini
there's been an ongoing discussion about how to hook up your gemini via ethernet/wifi
i'm thinking of doing a zoom meeting or possibly facebook live this weekend to go through this setup. (we are eventually going to do a tutorial video on this, so think of it as a dry run to see what questions come up)
maybe sunday as several people are getting their routers on saturday
what interest/preference is there for something like this?
(the discussion is here if you are interested)
I recommend and use this particular microRouter:? ?)
you will need at least 2 ethernet cables (cat5/6)
-- Brian?
Brian Valente portfolio
|
Re: Question for Brian Valente (not Losmandy related)
Thanks, Brian, I sent you a PM. It is unrelated to Losmandy but related to other astrophotography equipment that you have some specific experience with.
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Mearl Balmer
David C. Partridge
Kenn
Matthew_B
Steve Elmore