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Losmandy G11 Gemini 2 question?

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#1 tomcody

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Posted 29 March 2013 - 08:40 AM

I am considering buying a G11 with Gemini 2. I sometimes like to use my mounts for just visual by just loosing the clutches and hand moving the scope to the target and letting the scope track at sidereal rate like the Losmandy digital drive will do. Is there a way to start up the Gemini system and just let it track in sidereal rate WITHOUT doing a star alignment on at startup? I have read all the Gemini manuals and information I could find on line and nowhere is this ability mentioned. Also if you can do this? will the limit alarms be an issue? I had a Takahashi EM200 and it would run as a dumb drive all night long but the Meade LXD650 that I have now will not even move without doing the star alignment first and won't allow push-to hand movement without tripping a limit. Can anyone shed some light on using the Gemini like it was just a digital drive doing push to positioning?
I am also considering just buying the Losmandy G11 with the digital drive but don't want to give up the go-to capability of the Gemini.
Thanks Rex :question:

#2 Hilmi

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Posted 29 March 2013 - 10:07 AM

It will work, but the limits will be an issue. Rene has been good so far, I am sure we could ask him to introduce a dumb mode and he would oblige.

#3 terry59

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Posted 29 March 2013 - 10:45 AM

Rene has been good so far, I am sure we could ask him to introduce a dumb mode and he would oblige.


I don't see how you can say Rene has been good. The catalog debacle is inexcusable. There was no communication with users who "upgraded" the firmware only to find they lost two catalogs and means I can never upgrade my firmware or lose those also.

That said, my GM-8 will track without doing a go-to. Limits? Change 'em if you need to.

#4 Fortune07

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Posted 29 March 2013 - 11:46 AM

I've had my G11 with the Gemini 2 for almost 2 years and have never done a star alignment. I do a polar alignment push the scope where I want and it tracks with no problems. If limits are reached, just change the limits manually

#5 Hilmi

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Posted 29 March 2013 - 12:35 PM

Terry,

I agree with you on that bit, when I said he has been good, I had been referring to the fact that he has implemented every feature I have requested except for the electronic mount balance feature

#6 tomcody

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Posted 29 March 2013 - 12:46 PM

I've had my G11 with the Gemini 2 for almost 2 years and have never done a star alignment. I do a polar alignment push the scope where I want and it tracks with no problems. If limits are reached, just change the limits manually

Jeff,
Thank you, that is the answer I needed! Just one more thing, what is you start up sequence on the hand controller?
Do you do a Quick start? then when the Manual control screen comes up, select the tracking speed and done? or something else?
Thanks,
Rex

#7 Fortune07

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Posted 29 March 2013 - 03:42 PM

Well Actually, I control with my lap top now, but all I ever did was, yes, Quick start and set the tracking speed and go from there.

#8 tomcody

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Posted 29 March 2013 - 03:50 PM

Thanks Jeff, with your answer, I feel safe in buying a G11 Gemin2 instead of getting the digital drive version.

I just wish that either the manual or the FAQ covered this question. I asked Rene about it and he said that I was the only person that ever enquired about running a Gemini2 this way.
With all the folks using classic refractors & mounts and push to type mounts, or wanting to upgrade from the digital drive mounts, I would have thought this issue would have come up more often?

P.S. my wife wants the Gemini also, she is strictly a go-to type of observer.
Rex

#9 Fortune07

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Posted 29 March 2013 - 07:07 PM

I don't think you will be disappointed with that combination. I am learning astro-photo and Things are a lot simpler when your not fighting the mount. The gemini 2 system is soooooo nice after using other mounts. (my two cents):smirk:

#10 dawziecat

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Posted 31 March 2013 - 02:48 AM

. . . users who "upgraded" the firmware only to find they lost two catalogs and means I can never upgrade my firmware or lose those also.


Rename the NGC and IC catalogs and save 'em. Then reload them as custom catalogs after the upgrade. Should work, no?
I rather doubt Gemini 2 is smart enough to detect the subterfuge.

#11 Raginar

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Posted 31 March 2013 - 09:18 AM

It's a mistake. It happens. Considering the usual technical support you get from companies once you've purchased your product, I'm very happy with my G2. They'll get the catalog thing sorted out. It's still better than my nexstar from a modeling standpoint. Park it, turn it back on, sync on one star and it's spot on.

From a technological standpoint, the mount is light years beyond the competitors. USB? Builtin. Ethernet? Built-in. Wifi? OK, I gotta add a module to do that. GPS? Yea, I gotta add one for that too.

OP: You can get running just by syncing on a star if you don't feel like building a model. The thing is, building the model doesn't take that much time. You're talking about maybe 15 minutes using the automated routine.

You'll love the mechanicals of a G11.

~Chris

#12 tomcody

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Posted 31 March 2013 - 01:33 PM

Thanks for all the replies. As a retired CNC/robotic technician, I know I will love this mount from the rather open firmware/software support, (how many companies give you instructions how to burn a new EEPROM? to the straight forward mechanical design? Again How many companies offer a list of most parts on their web sight along with shopping cart buying? From what I have read, Losmandy is well on their way to addressing and fixing the rather high periodic errors that were the only detraction to the mount in years past and should be a good steady seller in the future. My only regret is in listening to all the detractors regarding that PE and paying too much for a Takahashi EM200 instead. A mistake I am fixing now.
Rex

#13 mistyridge

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Posted 31 March 2013 - 03:27 PM

As a old star hopper from the 1960s I thought of using my G11g2 as a push to mount, but was unsure if it would work or just screw something up. Since I already have a ALT/AZ DM-6 with sky commander, the G11 never gets used. The only part used is the HD tripod. I just listed the G11 head and g2 on the S&S forum. It appears I can use it like the digital drive I may keep it. I will post this as a separate question.

#14 Dan Finnerty

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Posted 31 March 2013 - 04:49 PM

It will work, but the limits will be an issue. Rene has been good so far, I am sure we could ask him to introduce a dumb mode and he would oblige.


The limit issue is easy to deal with. Put your mount/OTA into the standard CWD position, turn on the G2 and choose "cold start" from the menu when it boots up. Other modes may work fine, but I've not bothered to check.

Then select a nice easy to find bright star from GOTO catalog. If the telescope looks like it is about to go too far in any direction, kill the slew by hitting any of the arrow keys. Manually move the telescope in the vicinity of the selected bright star and GOTO it again. When it arrives in the vicinity, manually point at the target. If you have a reasonably wide-FOV eyepiece in the scope, it will be easy to center it. Then select Alignment - Sync. That will sync the mount to the coordinates of the selected star. You can then use gotos to get in the vicinity of your desired target without worrying about hitting slew limits. You will likely need to manually tweak pointing to center, but it will be close. And you can always re-align to tell the mount/G2 computer where it is pointing.

This does not build a pointing model, but it is good enough for quick and dirty pointing purposes. Any time you manually point the telescope to a new target, sync to it and you will alleviate any limits problems.

I have spent many an evening fighting with the mount to get initial alignment done and have found that if I just want to look at the moon, a planet or two and a few known star clusters this works fine and saves a few hassles.

And if I need to build a model to get precise gotos I still can at any time.

#15 mistyridge

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Posted 31 March 2013 - 05:03 PM

Thanks Dan.

#16 Billydee

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Posted 31 March 2013 - 05:25 PM

Terry Danks,

I suggest you remove your suggestion about renaming the catalogs. You are not allowed to use these catalogs without payment of a fee. Your suggestion leaves you open to a lawsuit and also libels the CN Forum. The problem is that Rene did get permission to use these in Gemini II software. This is no small issue.

Bill

#17 Dan Finnerty

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Posted 31 March 2013 - 11:20 PM

Bill,

that sounds over the top to me. I paid for the mount with its software and catalogs. If there is a bug in the software and I have to work around it until a new update becomes available this renaming does not seem unreasonable to me. It is not like I'm redistributing the catalogs anywhere or using them for a purpose for which they were not intended.

I've not been following this issue on the Yahoo G2 forum, has any one else? What are they saying to do there? Tom and Rene comment regularly there, I would think they would raise a concern if there were an issue.

Moderators what do you think?

#18 Hilmi

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Posted 01 April 2013 - 12:14 AM

I think you misunderstand. It is not a bug. What happened was Rene found out his permission to use the catalog on the the Gemini 1 is not legally applicable to the Gemini 2 and he was forced to remove it.

By installing these Catalogs without the license you are basically using pirated software.

#19 Dan Finnerty

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Posted 01 April 2013 - 01:10 PM

Ah. That is a different situation entirely. That is what I get for dropping into the middle of a thread!

#20 Startraffic

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Posted 02 April 2013 - 11:55 AM

Hilmi,
Actually the limits are less of an issue if you're doing a push to. Since the clutches are loosened to the point of "just holding things" with a push to setup the limits could be removed. It won't matter if you get a collision, the clutches are loose enough the the mount just stops moving even though the motors keep turning. That IS the way it was designed. The clutches should be loose enough to slip without damaging the gearbox or motor itself. I deliberately keep my clutches snug enough to prevent slippage, but not so tight that the gearbox or motor will be crushed in the event of a mount collision.
My $0.0125" worth

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#21 Hilmi

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Posted 02 April 2013 - 01:27 PM

I wouldn't know. I am too dumb to find my own way around the sky and see little appeal in non goto operation.

#22 pfile

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Posted 02 April 2013 - 05:42 PM

my 2c is that if you are doing imaging, think carefully. you may get a unit with really high PE (and fast PE) which is not guidable at longer focal lengths.

if you are doing visual it should be fine, i suppose, though with 30+ arcsec pk-pk, you may see that in the eyepiece.

if you are comfortable tearing apart the mount and switching/upgrading worms, then i suppose it's no big deal.

as for G2, all i can say is that when you buy a 99 cent app on your iphone and an update is available, there's usually a changelog saying what bugs were fixed and what new features are available. not so with the G2 and as people have noted above the catalog issue is a big deal. plus not even knowing if bugs you've seen/reported have been addressed makes deciding to upgrade difficult.

according to tom, there has *never* been a changelog for any G2 firmware upgrade, which is kind of silly.

#23 mistyridge

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Posted 02 April 2013 - 06:06 PM

I did my last update last year. I think it was in July. Gemini 2 works well enough for me as is. So, until the final, final update is ready I will use the mount as is since I just do a some planetary imaging/viewing or star hop. Accurate goto is not crtical for me if g2 can get me to a familiar part of the sky.

#24 saadabbasi

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Posted 02 April 2013 - 06:12 PM

according to tom, there has *never* been a changelog for any G2 firmware upgrade, which is kind of silly.


Silly or not, it's very amateurish.

#25 urbanMark

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Posted 02 April 2013 - 09:17 PM

my 2c is that if you are doing imaging, think carefully. you may get a unit with really high PE (and fast PE) which is not guidable at longer focal lengths.

if you are doing visual it should be fine, i suppose, though with 30+ arcsec pk-pk, you may see that in the eyepiece.

if you are comfortable tearing apart the mount and switching/upgrading worms, then i suppose it's no big deal.

as for G2, all i can say is that when you buy a 99 cent app on your iphone and an update is available, there's usually a changelog saying what bugs were fixed and what new features are available. not so with the G2 and as people have noted above the catalog issue is a big deal. plus not even knowing if bugs you've seen/reported have been addressed makes deciding to upgrade difficult.

according to tom, there has *never* been a changelog for any G2 firmware upgrade, which is kind of silly.



To the best of my knowledge, the only G11's with high/fast PE's are older units that still have the steel worms. You can purchase a new brass worm from Losmandy for $60, and replacing the worm is easy. I'd hardly call it "tearing into the mount". Obtaining a smooth PE with peak to peak under 10 arc-sec (i.e. +-5 arc sec) should be very straightforward for anyone with basic mechanical skills. If you are willing to spend for the Ovision or the OPWB then peak to peak of 5 arc sec or better should be possible. Mechanically I think the mount is a steel of a deal, esp used.

Regarding G2, I have to agree I am amazed that this has basically been treated as a hobby project. Hard to believe this is all done by one guy (Rene) and I don't even know if he is being paid. Tech support is basically Tom on the Yahoo group, who is not paid at all. All that said, the G2 system is very advanced and is working great for my needs. Yes, updates have been slow as molasses (was nearly 2 years before we had PEC), there are no change logs or bug lists, and the catalog issue was poorly handled. Still, I repeat, it is working great for my needs, both visual and imaging.

Bottom line, even with the issues, the G11/G2 is a great system for both visual and observing. Certainly there are better mounts, and they have the price tags to prove it.






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