On Tue, Jan 28, 2025 at 05:10 PM, Thomas Kallenbach wrote:
Hello,
I was wondering if my recent question has been approved for the forum.
Thanks,
Tom
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It has and you’ve already received a couple of suggestions:
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Hello, I was wondering if my recent question has been approved for the forum. Thanks, Tom
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Re: RA guiding awful after upgrade
After making any mod like this you should do a new polar alignment, a new PEC curve (if you do that), and a new guiding steps calibration. Also make sure you are still balanced and redo carefully. The extensions themselves should not cause an issue.? Also be careful to not to judge guiding from one night's results as seeing could have a big impact.
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Regards.
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John
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Losmandy G11G2 on pier; refurbed Losmandy G11 with OnStep controller; SkyShed design roll-off observatory; ZWO ASI2600MM-P; ZWO ASI071MC; Sky-Watcher Esprit 100 ED with field flattener; Celestron C925 Edge HD with 0.7XFR, William Optics Zenithstar 61 APO; PHD2, NINA, Sequence Generator Pro and PixInsight user
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On Mon, Jan 27, 2025 at 02:22 PM, Michael A. Covington wrote:
Where does one get the kind of washer you recommend?
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On Jan 27, 2025, at 16:33, Chip Louie via groups.io <chiplouie@...> wrote:
[Edited Message Follows]
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The use of flat thrust bearings is really not needed, there should never be that much force on the lock knob/lever.? If you really feel compelled to mess with the adjustment locks a good cheap compromise modification is to put a ground SS washer under each of the lock knob/lever with a thin plastic washer between the new SS washer and the GM8 or G11 base.? This promotes easier adjustment movement while reducing the undesirable mount movement when the knobs start to get snugged down.?
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I mention using a precision ground SS washer because they will introduce less movement during tightening of the lock knob/lever.?
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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Any good hardware store will carry flat ground washers as well as various plastic washers.? Use a slippery plastic, like most types of polyethylene, PTFE or in a pinch I've cut slippery washers from white plastic gallon milk jugs LOL.?
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Also McMaster Carr has these parts as well as nice adjustable handles and knobs to substitute if that's your thing.? But like I mentioned previously it takes minimal torque to reliably hold the elevation or azimuth adjustments.??
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Backlash has nothing to do with the force needed to hold the adjustment.? You should have enough preload on the locks to just hold the mount during the time you use the adjusters.?
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Think of this as two are two different operations, adjustment and locking that unfortunately interact slightly when the locks are applied.? Using ground washers with low friction plastic washers is cheap and more effective than using a thrust washer alone as they remove much of the cause of shift in the adjustment.??
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This little change works for both the old original type adjustment locks where the knob holds the threaded rod and the newer fixed stud used with a knob with a threaded insert type adjustment locks.?
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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Re: RA guiding awful after upgrade
Hi Tom, hard to tell what’s changed in your setup, but I’d at least check the balance in Dec and RA and make sure the additional hardware hasn’t affected the worm/gear mesh.
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Regards,
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? -Paul
On Tue, Jan 28, 2025 at 12:49 AM, <Tjkallenbach@...> wrote:
Hello,
I bought an RA extension and 12" pier extension for my g11.? The goal was to improve meridian flips with my 130mm refractor. I checked all the screws in both components and they are tight.??
Guuding was good before the extensions .3 to .7 I. Both RA and DEC.? Now, DEC is still good, right now it's 0.4 but RA is 1.5, 1.8, 2.2 or more.? Last light after the flip it improved.? Tonight I moved the CW to make it east heavy.? That did not really help.? I have tried adjusting the aggression but that doesn't make much difference (I use an ASIAIR).? Again, the problems started with the new RA and pier extensions.? I hate to lose the first clear nights in two months so any suggestions are appreciated.? ?
Tom
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RA guiding awful after upgrade
Hello,
I bought an RA extension and 12" pier extension for my g11.? The goal was to improve meridian flips with my 130mm refractor. I checked all the screws in both components and they are tight.??
Guuding was good before the extensions .3 to .7 I. Both RA and DEC.? Now, DEC is still good, right now it's 0.4 but RA is 1.5, 1.8, 2.2 or more.? Last light after the flip it improved.? Tonight I moved the CW to make it east heavy.? That did not really help.? I have tried adjusting the aggression but that doesn't make much difference (I use an ASIAIR).? Again, the problems started with the new RA and pier extensions.? I hate to lose the first clear nights in two months so any suggestions are appreciated.? ?
Tom
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I don’t have a lot of experience with mounts since I’ve only owned two Losmandys so, I have no idea what a great adjustment system looks like or how they work ;). However, on both my mounts the Alt knob is quite good with no perceivable backlash. The AZ does have perceivable backlash but it’s easy to work around it. The idea is to work from just one side so, if you are east of the pole and need to move west, move the knob a little in that direction and, the closer you get to a good PA the less you turn the knob so that you don’t go past the pole. Presumably, if you happen to go past it, it will be by a negligible amount and you can leave it like that.
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If you use digital means of PA the process is quite easy and quick. If you do a drift alignment it can take quite a while because of the necessary small movements needed to prevent switching direction, and the slow nature of the procedure to begin with
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My 1.5 cents (not enough info to make up the entire 2 cents lol)
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Jonathan
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Thanks, Bill. Very helpful! The important point is that it sounds as if the GM8 adjustors are very workable, if not as good as my A-P 1200GTO (on which they are very good). Nothing can be as bad as the adjustors on my MI-250. That’s a great mount, except for the adjustors. In fact, it’s on my list to take the scope off the MI-250 and see if I can rebuild ‘em to something better. It really is a nice mount otherwise! ? Greg ?
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From: [email protected] <[email protected]> On Behalf Of Bill Tschumy via groups.io
Sent: Monday, January 27, 2025 5:55 PM
To: [email protected]
Subject: Re: [Losmandy_users_io] GM8 alt/az adjustors? Greg, I will be a bit of a contrarian here. ?I find there is quite a bit of slop (backlash) in the adjusters. ?Others here have commented on it before so I don’t think it is just me. ?When reversing direction while adjusting the Az there is probably a good 1/8th revolution before it starts actually moving the Az. ?There is a big change in torque needed when this happens so it is easy to know when you are actually moving it. The Alt is a bit stranger. ?There is also what feels like 1/10th revolution of slop before it tightens and it starts moving the Alt in the opposite direction. ?However, I do find that sometimes, even when it feels like I’m in the backlash zone, I do see the Az move. ?Not sure why sometimes it move immdiately when reversing and sometimes not. Even with this backlash, I find it pretty easy to adjust the polar alignment. ?It is not really an issue for me. Bill
On Jan 27, 2025, at 11:13?AM, Greg Hartke via groups.io <ghartke@...> wrote: ? Thanks, guys. That helps! I have plenty of experience with GEMs and know what great adjustors are like (my A-P 1200GTO) and sketchy adjustors (my MI-250). Adjustors that work properly make PA an enjoyable task and (conversely) those that are sketchy make it truly frustrating. I do indeed use Chip’s methodology (experience tells!) and I infer from Bill’s comment that the GM8 adjustors are good, but not great. They sound good enough to be worth trying.
Otherwise -- Longmont, CO ? ?
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Greg,
I will be a bit of a contrarian here. ?I find there is quite a bit of slop (backlash) in the adjusters. ?Others here have commented on it before so I don’t think it is just me. ?When reversing direction while adjusting the Az there is probably a good 1/8th revolution before it starts actually moving the Az. ?There is a big change in torque needed when this happens so it is easy to know when you are actually moving it.
The Alt is a bit stranger. ?There is also what feels like 1/10th revolution of slop before it tightens and it starts moving the Alt in the opposite direction. ?However, I do find that sometimes, even when it feels like I’m in the backlash zone, I do see the Az move. ?Not sure why sometimes it move immdiately when reversing and sometimes not.
Even with this backlash, I find it pretty easy to adjust the polar alignment. ?It is not really an issue for me.
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On Jan 27, 2025, at 11:13?AM, Greg Hartke via groups.io <ghartke@...> wrote:
Thanks, guys. That helps! I have plenty of experience with GEMs and know what great adjustors are like (my A-P 1200GTO) and sketchy adjustors (my MI-250). Adjustors that work properly make PA an enjoyable task and (conversely) those that are sketchy make it truly frustrating. I do indeed use Chip’s methodology (experience tells!) and I infer from Bill’s comment that the GM8 adjustors are good, but not great. They sound good enough to be worth trying. ? Appreciate the help! ? Greg ?
--? Bill Tschumy Otherwise -- Longmont, CO www.otherwise.com
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Where does one get the kind of washer you recommend?
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On Jan 27, 2025, at 16:33, Chip Louie via groups.io <chiplouie@...> wrote:
? [Edited Message Follows]
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The use of flat thrust bearings is really not needed, there should never be that much force on the lock knob/lever.? If you really feel compelled to mess with the adjustment locks a good cheap compromise modification is to put a ground SS washer under each of the lock knob/lever with a thin plastic washer between the new SS washer and the GM8 or G11 base.? This promotes easier adjustment movement while reducing the undesirable mount movement when the knobs start to get snugged down.?
?
I mention using a precision ground SS washer because they will introduce less movement during tightening of the lock knob/lever.?
?
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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The use of flat thrust bearings is really not needed, there should never be that much force on the lock knob/lever.? If you really feel compelled to mess with the adjustment locks a good cheap compromise modification is to put a ground SS washer under each of the lock knob/lever with a thin plastic washer between the new SS washer and the GM8 or G11 base.? This promotes easier adjustment movement while reducing the undesirable mount movement when the knobs start to get snugged down.?
?
I mention using a precision ground SS washer because they will introduce less movement during tightening of the lock knob/lever.?
?
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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Good data point, Michael. Thanks! It really sounds to me as if the GM8 might be among the best light (lighter?) weight non-strain wave mounts available today. ? You’ve been around a long time, so you’ll appreciate this: Way back in the day when I was imaging with an LX-200, I found the adjustors on the Super Wedge to be pretty bad. I modified those babies to incorporate thrust bearings which made the adjustor motions ridiculously smooth and solid with very repeatable adjustment. The result was that ?the modified Super Wedge had the best adjustors of any mount I’ve ever used, even better than those on my A-P 1200GTO. From this, I learned that good adjustors with little backlash and repeatable motions make polar alignment (drift alignment, of course) really easy. ? Greg ?
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-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Michael A. Covington via groups.io
Sent: Monday, January 27, 2025 1:30 PM
To: [email protected]
Subject: Re: [Losmandy_users_io] GM8 alt/az adjustors ? I can tell you the GM8 adjusters are much better than the CGEM or AVX. The secret, as has been noted, is not to loosen them more than necessary when you're going to move them.? I installed knobs so no tool is needed to loosen or tighten.? Some backlash is probably desirable, not something to eliminate. ? ? ? ? ? ?
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I can tell you the GM8 adjusters are much better than the CGEM or AVX.? The secret, as has been noted, is not to loosen them more than necessary when you're going to move them.? I installed knobs so no tool is needed to loosen or tighten.? Some backlash is probably desirable, not something to eliminate.
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Thanks, guys. That helps! I have plenty of experience with GEMs and know what great adjustors are like (my A-P 1200GTO) and sketchy adjustors (my MI-250). Adjustors that work properly make PA an enjoyable task and (conversely) those that are sketchy make it truly frustrating. I do indeed use Chip’s methodology (experience tells!) and I infer from Bill’s comment that the GM8 adjustors are good, but not great. They sound good enough to be worth trying. ? Appreciate the help! ? Greg ?
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From: [email protected] <[email protected]> On Behalf Of Chip Louie via groups.io
Sent: Monday, January 27, 2025 9:48 AM
To: [email protected]
Subject: Re: [Losmandy_users_io] GM8 alt/az adjustors? On Sun, Jan 26, 2025 at 11:36 AM, Greg Hartke wrote: How good are the alt/az adjustors on the GM8? As someone who has to setup and tear down for each session, it’s important to me that these adjustors work well with minimal backlash to make polar alignment as straightforward as possible. Thanks! ? Greg
Many of us here are portable mount users, the adjusters and adjustment locks work fine if you know how to use them.? My best advice.on adjustment is to only loosen the adjuster locks just enough to allow the mount hardware to move a little bit as the adjusters are turned.? Once adjusted don't apply excessive torque to hold the adjustment in position, use just enough to hold the setting no more.? If you follow this advice you'll have an easy time getting a good polar alignment.??
Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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On Sun, Jan 26, 2025 at 11:36 AM, Greg Hartke wrote:
How good are the alt/az adjustors on the GM8? As someone who has to setup and tear down for each session, it’s important to me that these adjustors work well with minimal backlash to make polar alignment as straightforward as possible. Thanks!
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Greg
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Many of us here are portable mount users, the adjusters and adjustment locks work fine if you know how to use them.? My best advice.on adjustment is to only loosen the adjuster locks just enough to allow the mount hardware to move a little bit as the adjusters are turned.? Once adjusted don't apply excessive torque to hold the adjustment in position, use just enough to hold the setting no more.?
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If you follow this advice you'll have an easy time getting a good polar alignment.??
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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circa '94 GM8. As long as you are reasonably close of course to have the play in the azimuth direction, I have never had an issue. Bill _____________ Pictor Observatory
Twitter: @pictorobs
Minor Planet 21350 - billgardner
How good are the alt/az adjustors on the GM8? As someone who has to setup and tear down for each session, it’s important to me that these adjustors work well with minimal backlash to make polar alignment as straightforward as possible. Thanks! ? Greg
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How good are the alt/az adjustors on the GM8? As someone who has to setup and tear down for each session, it’s important to me that these adjustors work well with minimal backlash to make polar alignment as straightforward as possible. Thanks! ? Greg
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Re: Ethernet may be kaput
Doh! It's back to life. Somehow the ethernet settings on the PC were trying to connect over tcp instead of udp. It's working now after I put the settings back to where they should be.?
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I've always used ethernet. Last night my system which was setup for ether wouldn't connect. I can't seem to get it to connect at all, and the lights are not on at the ether plug on the gemini. They are on on the PC side. Probably kaput right??
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Re: 1st time Gemini 1/G11 use
On Thu, Jan 23, 2025 at 04:42 PM, <thomas.clark@...> wrote:
Hi all. I'm new to Groups, and new to the hobby. I am set up with a very old C-11 on a G-11, with G-1 controller. It has power but is not tracking well.?
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I don't want to be in the 'wrong section', ask the wrong questions, or otherwise agitate others.?
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I know that someone knows how to do it/everything the easy way. IDK if I am on the correct settings on the unit itself. It's tracking, but not following the object.?
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What am I doing wrong?
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Thanks,
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TC
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Welcome to the Losmandy groups!? Many of the folks here are long time users and have a ton of useful info and I hope you find us helpful and that you become part of this great community of users.?
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As a G11 Gemini 1 user the best places for you for all things related to the G11 and Gemini 1 are this group, the Losmandy_users group and the Gemini_users group? Joining these two will get you 99% of the applicable information specifically for your G11 mount and Gemini 1 controller.? BUT if you also join the GeminiII group you will also find great nuggets of wisdom as well as get a handle on your next controller for the future time when you want to make the jump to the latest generation of Gemini controllers.? ?
If anybody gets annoyed by you asking question related to Losmandy or Gemini gear that's on them.? We all get along here and if the thread is really not related to the sub group or gets out of hand the mods will say so and move the thread.? In other words don't worry about it, easy peasy.
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Anyway - to answer your question the G11 is an equatorial mount and like all EQ mounts it needs to be setup a certain way to work as designed.? The main issue with the actual mount hardware is that the RA axis needs to be pointed accurately at the North Celestial Pole - NCP for short - and if you do not know it Polaris is NOT the same as the NCP.? The other thing is that the Gemini needs to be configured correctly for your location and know what time it is.? Sounds simple but there are also a few other settings you need to get right for it to actually work and a few more to get it to work well.?
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As others have mentioned there is a dated but still relevant manual for the Gemini 1 located here: written by the guy who wrote the internal code the Gemini 1 is running.? The later Gemini 2 controller is based on the same ideas and at its core very similar.? That said the most useful Gemini related website IME is the website which has basically ALL the Gemini 1 and Gemini 2 stuff in one place.? ? ? ?
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Review these sites, ask questions and let us help you find your way through the Gemini and to a happy tracking mount place.??
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My quick off the top advice is to buy some new batteries for the Gemini 1, to find the correct type of batteries go to the Gemin-2.com site and look at the identification photos to determine what version Gemini 1 you have in hand.? A marginal or expired battery is the #1 issue for most new Gemini owners both Gemini 1 & 2 with a used Gemini.? Trust me just get a few new name brand batteries of the correct type and leave them in the case with the Gemini controller as having a couple spares will pay off in the middle of the night at a dark sky site hours from home as the Gemini 1 controllers are known to eat batteries regularly.?
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Next remove the battery and wait 30 seconds then reinstall the battery and immediately manually set up the Gemini 1 to UTC time, set any local time zone offset, GPS coordinates, mount type etc.? This is the minimum data the mount needs to operate but there are other setup requirements to achieve good tracking and GOTOs the obvious being excellent polar alignment and a known good power supply.??
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Keep us posted on your adventure!?
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Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
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Paul Kanevsky
Chip Louie
Bill Tschumy
Jamie Amendolagine