A few questions on Losmandy G11 G2

Manav (Yugant) · #1 17-11-2012, 03:40 PM

Hi guys,

I'm in the market for the G11 G2 and had a few questions regarding the mount as follows:

1. What's the PEC (p-p) range for the mount? I've heard PEC can vary mount to mount and need to know what I can expect.

2. Is it worthwhile to upgrade to the single worm block since the existing ones have the 76 error?

3. Do the new G11's have a different motor or is it still the Hurst stepper motors?

Let me know

Regards

TrevorW · #2 18-11-2012, 12:41 PM

Plus or minus 5 arc seconds or better remember this is not a AP or Bisque mount, but is the best step up or two IMO from an EQ6 both in price and performance.

Made in America very solid and very well supported. All I can suggest is do some homework check out the Yahoo Losmandy Gemini forums

I'm selling mine only because it's taking up room, I have no space for an observatory and it's not being used as often as it should.

Cheers

Check out this thread when I was asking the same questions

http://www.iceinspace.com.au/forum/s...ad.php?t=71821

wasyoungonce (Brendan) · #3 19-11-2012, 10:24 AM

The reason I purchased a G11 is that I wanted a mount that would last for a long time....and I could buy any part I needed as a spare to keep it in tip top service.

1. Current G11 PE is around +/- 5 arc seconds PP (or better) out of the box. This was due to Losmandy changing to a newer High Precision Worm (HPW), around early/mid 2009 onwards. G11's prior to this had a little larger PE (on average) but this can be reduced by installing a HPW.

2. The new One Piece Worm (OPW) block allows better orthogonality and adjustment of the worm train and some users have reported PE as low as +/- 2 arc seconds PE. I haven't upgraded to the OPW as my mount came with a PE of +/- 4 arc seconds and the errors were easily guided out. A lot of this depends on the scope used. Some scopes demand more of the mount (ie: a long refractor) and PE can be worse or better.

Since the OPW keeps the worm and bearings in alignment then the 76 second tick should reduce (the tick is caused by worm tight spot caused by misaligned worm bearings).

3. The G11's come in 2 flavours of control systems: The Digital drive system (non-go-to), which uses a stepper motors (from www.mechtex.com); and The Gemini2 (go-to) which uses servo motors. You could purchase the Gemini system with higher torque Maxon servo motors although I don't see that on their website at the moment. I never felt the need for these but that's my opinion.

An answer without a question...get a G11 with Gemini2...IMHO

.

Hope this helps.

mithrandir (Andrew) · #4 19-11-2012, 11:56 AM

Quote:

Originally Posted by wasyoungonce

3. The G11's come in 2 flavours of control systems: The Digital drive system (non-go-to), which uses a stepper motors (from www.mechtex.com); and The Gemini2 (go-to) which uses servo motors. You could purchase the Gemini system with higher torque Maxon servo motors although I don't see that on their website at the moment. I never felt the need for these but that's my opinion.

Brendan, Losmandy are changing the Gemini motors again.That might be why there aren't any shown on the replacement parts page. A mount ordered now might have Maxons or the new ones depending on when it was built.

wasyoungonce (Brendan) · #5 19-11-2012, 02:24 PM

Ahhh thanks Andrew. They are probably changing due to availability issues? Suppliers never last forever.

The old one's were not cheap but they are repairable.

mithrandir (Andrew) · #6 19-11-2012, 05:15 PM

Quote:

Originally Posted by wasyoungonce

Ahhh thanks Andrew. They are probably changing due to availability issues? Suppliers never last forever.

The old one's were not cheap but they are repairable.

The new ones are supposed to have more torque, but are also alleged to be noisier (but that might be in the gearboxes). There has been some talk about them on various Y! Losmandy groups.

White Rabbit · #7 20-11-2012, 01:47 PM

Hi guys.

i too am looking at getting one.

can anyone tell me if the bugs have been ironed out of the Gemini 2 software. When it frist came out, as I understand it the software was no where near complete. Has this been rectified?

thanks

TrevorW · #8 20-11-2012, 05:31 PM

In a short answer "Yes"

White Rabbit · #9 20-11-2012, 05:49 PM

Mmmm, what would the long answer be??? Lol

wasyoungonce (Brendan) · #10 20-11-2012, 06:06 PM

A visit to the Gemini 2 yahoo group might help.

I have a G1 but from what I can tell, the early teething issues have been well sorted and the system is quite usable. A few things still need attention but these are being done.

This is no LX800 disaster here.

Geoff45 (Geoff) · #11 20-11-2012, 07:20 PM

Maybe I was unlucky to get a buggy mount, but I could never get consistent guiding with my g8. Finally resorted to an SX-AO unit, after which round stars and 30 min exposures were the go. Still, based on my experience I'm pretty much turned off Losmandy mounts.
Geoff

mithrandir (Andrew) · #12 20-11-2012, 07:41 PM

Quote:

Originally Posted by ghsmith45

Maybe I was unlucky to get a buggy mount, but I could never get consistent guiding with my g8. Finally resorted to an SX-AO unit, after which round stars and 30 min exposures were the go. Still, based on my experience I'm pretty much turned off Losmandy mounts.

It might be a bad mount, but if you were using the 12" newt in your sig on a G8 that is pushing the envelope. The G8 was designed for an 8" SCT - hence the name.

Geoff45 (Geoff) · #13 20-11-2012, 08:40 PM

Quote:

Originally Posted by mithrandir

It might be a bad mount, but if you were using the 12" newt in your sig on a G8 that is pushing the envelope. The G8 was designed for an 8" SCT - hence the name.

Nope--only used the 4" refractor. I'm not that crazy!
Geoff

Manav (Yugant) · #14 21-11-2012, 12:07 AM

Quote:

Originally Posted by wasyoungonce

An answer without a question...get a G11 with Gemini2...IMHO

. Hope this helps.

Thanks everyone for your replies!

Brendan - So the suggestion is that I get the standard G11 G2 and not bother with upgrade just yet.

I'm tempted to ask the Australian retailers to do a PEC (p-p) for me before purchase. I don't want to stuck with a dud especially as I've heard a 1 or 2 horror stories with G11 purchase and very high pec.

I'm already in touch with Peter from ATS and will request if he can do this for me.

wasyoungonce (Brendan) · #15 21-11-2012, 09:03 AM

Quote:

Originally Posted by Manav

Brendan - So the suggestion is that I get the standard G11 G2 and not bother with upgrade just yet.

I'm tempted to ask the Australian retailers to do a PEC (p-p) for me before purchase. I don't want to stuck with a dud especially as I've heard a 1 or 2 horror stories with G11 purchase and very high pec.

I'm already in touch with Peter from ATS and will request if he can do this for me.

I doubt that a retailer will do a PE test run prior to sale.....you never know though,....cannot hurt to ask!

You can be pretty assured you will get a mount with +/-5 arc sec's or better PE these days. The PE is adjustable via the worm blocks. If it's high or "wild" then there is something wrong or it is not adjusted properly.

I believe all mount worms are adjusted by Scott Losmandy prior to boxing. He mentioned something like that a few years back on a Yahoo forum. Could be a tall story though

.

IMHO...now's the time to buy with the $Aust high.

Capricorn1(Tom) · #16 21-11-2012, 09:47 AM

I see Robert has a G11 Gemini 1 with hand made containers. See his post in the for sale section. I would have bought my self, but just purchased and recieved a G11s from bintel for my C14. The quality of the G11s leave the chineese mounts for dead ( I also have a HEQ5 Pro for my WO Megrez 88) next couple of years will upgrade to the Gemini Kit......Cheers

Manav (Yugant) · #17 21-11-2012, 10:29 PM

Its a G1 but the price is tempting. God what do I do?

Brendan is it worth splurging extra for the G2?

mithrandir (Andrew) · #18 21-11-2012, 11:53 PM

Quote:

Originally Posted by Manav

Its a G1 but the price is tempting. God what do I do?

Brendan is it worth splurging extra for the G2?

You can probably get a used G11+G1 faster and later upgrade to a G2 for less than a new G11+G2. If the 76 sec behaviour is unacceptable, the Ovision upgrade is probably better than the Losmandy one but is more expensive.
I'm in no hurry to replace my G1. I'll probably wait until it fails. You do want a 1.0.4 or 1.0.5 EPROM. Those aren't user upgradable without an EPROM programmer whereas the G2 is. ATS can program EPROMs for you.

marki · #19 22-11-2012, 12:57 AM

There is a second hand G11 GII for sale in the classifieds.

Mark

wasyoungonce (Brendan) · #20 22-11-2012, 09:08 AM

Quote:

Originally Posted by Manav

Its a G1 but the price is tempting. God what do I do?

Brendan is it worth splurging extra for the G2?

IMHO get a G2 unless the G1 price is right. You can upgrade from G1 to G2 for ~$1k. You re-use the motors and change the controller and handset. I'm keeping my G1 till it dies...although repairing them is pretty easy for me...so it may never die!

.

The G1 is a nice kit, a bit dated, has some small quirks and is subject to damage if you plug in the motor connections wrong way around (these leads carry +12V for motors and encoder pulses). There are at present plenty of parts available for G1.

The G2 is much more modern, still a little dated in they way it presents information (IMHO), but, connectivity is excellent and they fixed the motor connection issue. Same connectors and motors (as G1) but different encoder IC's that withstand miss-connection.

I like the way the Gemini handsets (G1/G2) present info...the facts...just the facts and they manner in which they work. I used a gotostar (Gotonova) 32 bit RISC 8 line LCD readout, very modern, bling bling. But the Gemini is much better in the way it works....it just works, does the job no fuss, 100% every time. Goto's are spot on.