Re: G11G Imaging Weight Capacity for Imaging?
Jim,
?
The stated imaging payload of the G11G is 60 pounds.? Many people with heavier and longer scopes are imaging on a G11G with good results.? My friend is imagining with a 10" f/8 Newt that is well over 65 pounds with good results.?
?
I routinely load the 20+ year old G11G mount with over 60 pounds and image with it.? My guiding is very good, still well under 0.5" PE.? I normally image with the bespoke Parallax / AstroTech130mm f/6 SDT which has an oversized steel tube and 3.7" focuser and a Losmandy Side-By-Side saddle plate with ADM ALT/AZ aiming device and Meade LX200 10" f/6.3 SCT with 3" Moonlite focuser etc. etc.? this is a very heavy payload.??
?
I think the buyer should not have a problem imaging with a G11G and 50 pounds of payload.?
?
--
Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
?
?
?
|
Re: G11G Imaging Weight Capacity for Imaging?
Is the G11G 60 pound spec for visual?? I usually use 2/3 or 3/4 of the stated load capacity for the imaging spec.
------------------------
Jim W
Phoenix, AZ. USA
Losmandy G11G w/ L6, NINA 3.0 / ASTAP, ASI2600MC Pro, Sky-Watcher Scopes, Canon L Lenses.
|
Re: Did my Gemeni 2 firmware become corrupt?
How about changing the battery in the Gemini2 box??
?
joe
|
Re: G11G Imaging Weight Capacity for Imaging?
Hello Jim,
?
It is my belief that yes you will be pushing the mount, the G11G,? you could be taxing the G11T also though not as bad.? I'm assuming that there is a dew shield involved too.? Either mount you will need the FHD tripod or one of those tripiers.? Stability starts at ground level, always.?? Also I'm assuming the scope is on a Losmandy bar, my opinion a cradle would be better but surely put you over the top.? Guiding should also be done with an OAG or ONAG, my opinion too.
?
That was at F10,? at F6.3 you should be better.
?
I had a C14 with a Homeyer cradle and a G11T, but I was visual and planetary.? That was three years ago, don't have the scope and my Neighbor has the mount.
?
Joe
|
G11G Imaging Weight Capacity for Imaging?
I have a prospective buyer for my G11G w/ LW tripod.? They know that the tripod will have to be upgraded to the heavy-duty tripod.? They plan to do DSO and planetary imaging with a 12” Meade SCT. ?Likely with and without a 0.63x FR/FF.? The F.L. of the scope at f/10 is 3048mm and at f/6.3 is 1,920mm.? They estimate the total weight of the imaging setup to be 50 pounds.
?
My questions are…?
- Is 50 pounds pushing to limits of the G11G w/ Heavy Duty Tripod for imaging?
- Is a F.L. of 3,048 or 1,920 pushing the limits of the G11G w/ Heavy Duty Tripod for imaging?
- Would they be better off with a G11T?
Its my understanding they have no experience with Losmandy mounts.
?
------------------------
Jim W
Phoenix, AZ. USA
Losmandy G11G w/ L6, ZWO AM5N, NINA 3.0 / ASTAP, ASI2600MC Pro / ASI533MM Pro, Sky-Watcher Scopes, Canon L Lenses....etc
|
Re: Unable to fully lock RA axis on G11
I wonder if this could be what is causing my jerky RA guiding.? Thinking that loose clutches might be the problem, I tightened them down pretty tight.
|
Re: Unable to fully lock RA axis on G11
This may be one of the messages we really need to get out -- that the clutches are not meant to be fully tightened, and what you should do is see how little tightening is sufficient to keep them from slipping with your setup.? For me, it is about 1/4 turn past the point where resistance is first felt.
|
Re: RA guiding awful after upgrade
Our weather degraded significantly since I last wrote.? In fact the blizzard Friday shut down like 150 miles of the interstate.? It has been cloudy and now we have an artic blast headed this way so our normal 5 below is going to 20 below this week.? That's without windchill.??
When the weather cooperates, the first thing I am going to do is remove the RA extension and see what I get.
Thanks for checking in.
Tom
|
Re: RA guiding awful after upgrade
?
?
So?? What happened?? Did you find the issue?? Keep us posted.??
?
--
Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
?
?
?
|
Re: Unable to fully lock RA axis on G11
On Fri, Feb 7, 2025 at 08:41 PM, <avishekaiyar@...> wrote:
Hello All?
?
I am a brand new user of Losmandy mounts. My past experience with GEMs has been limited to the iOptron SGP and the Vixen GPDX.?
?
I recently acquired a Celestron Losmandy G11.?
?
I tried to counterbalance my setup today and had a clarification about the RA axis.?
?
No matter how much I tighten the RA clutch knob I am unable to fully lock the RA axis movement (and I really tightened the clutch). The Dec axis is fine....I am able to fully lock down that axis when I tighten the Dec clutch.?
?
Is this normal ? As an example when I deliberately throw the RA axis off balance by moving the 11lb counterweight all the way towards the end of the shaft, the mount easily rotates about the RA axis even when fully tightened down.?
?
This has definitely not been my experience on the other gems I have used...
?
Would appreciate any advice.?
?
Sincerely?
?
Avi?
?
Do you recall the scene in Star Wars when Luke is introduced the his father's lightsaber?? The core of the Losmandy mount design is a lot like that lightsaber.? The G11 and GM8 were designed in a more civilized age, from a more elegant time.??
?
When the G11 was designed we used to be able to see the sky and learned how to navigate it.? Everyone learned the night sky and used the Thomas Bros. Map book of the sky called Sky Atlas 2000.? There were no GOTO "blasters" there was only personal knowledge and the skill needed to PUSH-TO your chosen object.? The original Losmandy Digital Drive simply moved the RA axis in sync with the local system and galaxy and you pushed the scope to your destination.?
?
To do this you needed a well designed, finely tuned machine and the mount needed to be well balanced with the scope in the saddle.? We ran the clutches fully or almost fully open / loose and used a finger or two to push the telescope tube to the desire object using personal knowledge and skill.? There was no need to lock the axis, this was simply unnecessary.?
?
With the advent or the Gemini and GOTO becoming the more widely used method of observation people with less skill could navigate the night sky once the learned some simple skills to align the mount with the night sky.? The advent of the GOTO computer brought many new observers to the hobby and the lack of knowledge caused a lot of frustration among the novices.? Those who couldn't or wouldn't adapt and invest the the time to learn these small skills usually left the hobby.??
?
There is no reason to cinch down the clutches on a Losmandy mount for GOTO or imaging use, none.? The only catch is the mount has to be in good mechanical condition (well adjusted, clean and lubed), the payload balanced in the saddle on 3 axis and you can not have any cable snags.? If your Losmandy mount meets these simple conditions it will guide very well, easily sub 0.5" error with only modestly snugged clutches.??
?
--
Chip Louie Chief Daydreamer Imagination Hardware?
Astrospheric Forecast - South Pasadena, CA?
?
?
?
|
Are you using the same cord when switching power supplies? Short might be in cord.
?
The LittleFuse 452-454 (Fuse F1) is just to the right of the power connectors but would not short the power supply on failure.
?
If your power cord has an automotive lighter plug , some have a fuse located in the metal tip but again this wouldn't cause a short.
?
I really think the cord is the prime suspect as the F1 fuse would prevent a shorted board from killing the power supply
?
Good Luck
Brian
|
Re: Unable to fully lock RA axis on G11
On Sun, Feb 9, 2025 at 12:24 AM, <avishekaiyar@...> wrote:
I just separated the RA and Dec axes and disassemble the RA assembly (remove spacer, wavy washer, 3 piece thrust bearing and finally the RA shaft).?
?
Everything checks out. The clutch pad looks in a really good condition too.?
?
If I had to really nit pick, I would say that the wavy washer has lost a lot of its waviness. :)?
?
But after reading some of the other comments, I sort of see the point. With the Dec axis removed, the RA movements are pretty "locked" when the RA clutch is tightened (I made sure not to over tighten....I tightened it and let go as soon as I felt some resistance ). So I think it's ok.?
?
I also saw in one of the Losmandy balancing videos, Brian Valente also mentioning that the Dec axis is a lot "freer" compared to RA..I felt the exact same way so I guess it's all design intent.?
?
Hi Avi,
?
The locks never absolutely grip things down without movement. There is still a little play if you turn them hard enough. So the scope will move a bit if you bump into it or if it is very unbalanced or starts to drag a cable. I gave up on the wavy washer and balance RA by cranking ALT down to 0 (but careful you don't tip over if trying that). You could try new discs anyway or try the Michael Herman high friction discs, as Derek mentioned). Getting enough stiction for a night's operation should not be a hard thing.
?
Good luck.
?
John
--
_____________________________________________________________________________________________________________________________________________________________________________
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
|
Re: Unable to fully lock RA axis on G11
Hi Derek,?
?
That makes sense.?
?
Thanks for pointing that out?
?
Avi?
|
Re: Unable to fully lock RA axis on G11
Dear John?
?
I just separated the RA and Dec axes and disassemble the RA assembly (remove spacer, wavy washer, 3 piece thrust bearing and finally the RA shaft).?
?
Everything checks out. The clutch pad looks in a really good condition too.?
?
If I had to really nit pick, I would say that the wavy washer has lost a lot of its waviness. :)?
?
But after reading some of the other comments, I sort of see the point. With the Dec axis removed, the RA movements are pretty "locked" when the RA clutch is tightened (I made sure not to over tighten....I tightened it and let go as soon as I felt some resistance ). So I think it's ok.?
?
I also saw in one of the Losmandy balancing videos, Brian Valente also mentioning that the Dec axis is a lot "freer" compared to RA..I felt the exact same way so I guess it's all design intent.?
?
Thanks.
?
Avi?
|
Re: Unable to fully lock RA axis on G11
It’s
not supposed to “fully” lock!.. I have Michael Herman’s high friction clutch
discs and a perfectly working G11 and with enough force, it’ll move..
It
doesn’t take much force on the knobs to sufficiently tighten the clutches..
Derek
?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of John Kmetz via groups.io
Sent: Saturday, February 08, 2025
7:50 AM
To: [email protected]
Subject: Re: [Losmandy_users_io]
Unable to fully lock RA axis on G11
?
Chances are your clutch discs are very oil and/or severely worn. You
will need to unscrew the clutch locks all the way off and pull the shaft up and
out of the mount to inspect. Remember the order of the knob, washers are
bearings and put back in the same order. Try wiping down the disc pad with
alcohol or some other solvent. If the discs are worn like a phonograph record,
they may need to be replaced. You can give them some extra life by doing a
light sanding and again wiping clean. You will need to clean the respective
upper and lower contact surfaces as well. But I would suggest ordering new ones
from Lomandy if they are really worn. This should give you some extra stiction
and allow the locks to grip down on something less slippery.
_____________________________________________________________________________________________________________________________________________________________________________
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
|
Not much I can say except send it for repair with motors, cables and HC. ?Hard to say what the issue is atm but in general they can be repaired?
?
cheers
--
Brendan
|
Yesterday I was balancing my 2008 Losmandy G11, Gemini-1 using servo-motor current draw to fine tune the balance. At one point I used the hand controller to move the telescope to point at the celestial pole with counterweight down. As it neared that position the mount gave a continuous tone like when a safety limit is reached. That was puzzling since it wasn't anywhere near the limit. So I switched the Gemini-1 off, thinking it just needed a reboot.
?
When I turned it back on there was no response, no startup beep, no lights on Gemini electronics chassis or hand controller. Then I saw the 17-volt power had no lights. So it seemed the power supply had died. So I brought out my old Pyramid 13.8 volt power supply and hooked it up. It too had the same symptom - when Gemini-1 was switched on, the power supply lights for voltage and current went off.
?
So two power supplies had same symptom - not supplying power with all lights on or connected to the Gemini-1 all lights go off. It's clear the problem lies with the Gemini-1, perhaps something like a dead short. I'll give another try today to see if a day's rest has corrected the problem. But the prognosis isn't good. Does anyone know if there is something that I can do, like a resettable circuit breaker or fuse?
?
I'll be contacting Michael Herman to see if he can resurrect my old Gemini-1. If that fails, perhaps buying a used Gemini-1 or new Gemini-2 would be the path forward. My 17 year old Losmandy G11 has been a stalwart in my astronomy adventure. It now resides inside Ocean Observatory, with slide off roof.
?
?
Presently the G11 is carrying a Celestron-8 with AT115EDT triplet refractor, like what is shown below.
?
?
So as can be expected, I'm eager to get my old Losmandy G11/G-1 back in service.
?
Best Regards,
Russ
|
Re: Unable to fully lock RA axis on G11
Hi John?
?
I will take a look right now and report back.
?
Thanks.
?
Avi?
|
Re: Unable to fully lock RA axis on G11
Avi,
?
Chances are your clutch discs are very oil and/or severely worn. You will need to unscrew the clutch locks all the way off and pull the shaft up and out of the mount to inspect. Remember the order of the knob, washers are bearings and put back in the same order. Try wiping down the disc pad with alcohol or some other solvent. If the discs are worn like a phonograph record, they may need to be replaced. You can give them some extra life by doing a light sanding and again wiping clean. You will need to clean the respective upper and lower contact surfaces as well. But I would suggest ordering new ones from Lomandy if they are really worn. This should give you some extra stiction and allow the locks to grip down on something less slippery.
?
John
--
_____________________________________________________________________________________________________________________________________________________________________________
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
|
Re: Unable to fully lock RA axis on G11
On 2/7/2025 11:41 PM, avishekaiyar via groups.io wrote: No matter how much I tighten the RA clutch knob I am unable to fully lock the RA axis movement (and I really tightened the clutch). The Dec axis is fine....I am able to fully lock down that axis when I tighten the Dec clutch. The clutches are just that.... friction clutches.? If any grease has made it onto the friction surfaces (and it will) they cannot be "locked".? NOR SHOULD THEY.? The more you tighten the clutches the more load you put on the thrust bearings.? The thrust bearings use cylindrical rollers that roll in a circle.? And if you think about the geometry of a cylinder rolling in a circle, it will be obvious that it CAN'T unless one end or the other slips.? And if they slip unevenly, you can get RA jumps.? So the tighter the clutches, the more drag and unevenness from the rollers. Once I realized this I tried running with very loose clutches and all my RA jumping went away.? I don't know if it made a difference but I also cleaned the thrust bearings and re-greased with MP-50 since in essence, the rollers are a high pressure sliding interface.? I normally tighten until I feel contact and then go a maximum of 1/8 to 1/4 turn farther.? But, I can even run with the RA clutch fully loosened..... the rig is well balanced (that is key) and simply the weight of the rest of the mount and load is sufficient to provide enough friction. My $0.02 anyway. Paul (another one) -- Paul Goelz Rochester Hills, MI USA pgoelz@... www.pgoelz.com
|
Chip Louie
BrianH
Russell Milton