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Vixen GPD2, Losmandy G11

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#1 ibn ezra

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Posted 12 April 2009 - 07:18 PM

I've had a Celestron CG-5 (ASGT) for about a year now and what I have learnt is that I really want a non-computerised GEM set-up. The goto functionality was initially exciting, but after a while it began to feel like one of those package tours where you see a lot, but don't really learn anything.

My requirements are fairly straight-forward:
1. Steady enough to support an 8" SCT or 4~5" refractor
2. Precision manual operation
3. Motorised for sidereal (and ideally lunar & planetary) tracking

Initially I had my heart set on the Vixen GPD2 which seems quite reasonably priced at $1300. But after adding motors, clutches, a controller, accessory tray and polar alignment scope the total package starts approaching $2000.

That made me take pause, so now I am inclined to go with the Losmandy G-11S (Equatorial Head, Digital Drive, Weight Shaft, HD Tripod & 21 lb. weight) starts at a much loftier $2,195.00, but includes motors and controller (as well as all three tracking modes unlike the Vixen) in the base price. Adding a polar scope and illuminator to the mix pushes the cost of the G-11 a bit higher though.

Three questions about the G-11S rig:
1. What is the $425 digital setting circle hardware accessory (and do I need / want it)?
2. Do I need the $125 clutch knob set to switch between manual and motorised operation (like on the Vixen)?
3. Is the G-11 significantly 'better' than the GPD2, and what are there any real pitfalls to the G-11 that I am not taking into account?

Thanks!
-ibn Ezra

#2 GShaffer

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Posted 12 April 2009 - 07:51 PM

You are going to get a number of opinions on this but the bottom line is the G11 is more mount than the Vixen. Both are pretty decent mounts but the G11 will tote a larger payload......I cant speak to the quality of the newer Vixens as I have their older brother the GP-DX.....though I dont think much has changed other than the color. I dont have a G11 but rather a G8 which directly compares capacity wise with the Vixen unlike the G11. While there is nothing I dislike about my Vixen I have to give the nod to fit/finish/craftsmanship to the Losmandy......

Unless you plan to buy a computer for Pushto function you dont need the DSC hardware option on the G11.

The LOS mounts are different in how they work from the Vixen....You set the clutches for whatever resistance you like the feel of and then just push it to where you want to go......soon as you release it, it is back to tracking....

The G11 has close to twice the load capacity......In as far as looks.....no comparision IMO.....Kinda like comparing a ford falcon to a ferrari.....both of them will get you there, but only one of them raises your blood pressure when you look at it :)

My G8 already had the clutch knob upgrade when I got it but I am sure there is some method in place for this adjustment on a stock one......so no I dont think it is a requirement.

YMMV
Greg

#3 tidroplane

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Posted 12 April 2009 - 09:44 PM

The G-11 will handle your 8" with no problems, the mount is very solid, I had a 152mm refractor on mine for some time and it was rock solid, as far as the clutch knob upgrade, it`s not a necessity, but they are nice. The DSC option is like having a "push to" go to and would make finding faint DSO`s much easier. I think you would be very impressed with the quality of the mount, I know I really enjoy mine! The G-11 could be the last mount you`ll ever need! Good luck with which ever you decide on,

#4 TomN

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Posted 12 April 2009 - 10:26 PM

I love my G11. Rock solid and reliable. I use my CR150, the a C8, and my various smaller refractors on it. The only drawback is the weight. It's not really easy to lug out into the yard....

#5 plyscope

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Posted 12 April 2009 - 11:37 PM

I have a GPD2 and it is a well made quality mount. Mine came standard with the polar alignment scope. I think the basic GP mount does not have the polar scope included.
I have not tried a G11 but as Greg says it is a much more capable mount. If you think you might go to a larger scope in the future it would make sense to get the G11 now. However the GPD2 will be lighter and more compact/portable mount. You might want to check the package pricing, it may be possible to get a better deal on the GPD2 with motors and controller included. But if the Vixen is only going to be a little cheaper than a G11 I would say go for the G11.

#6 lowdog

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Posted 13 April 2009 - 02:15 AM

I agree with with everything said so far. I have both mounts, the GPD2 w/Starbook-s and G11 W/Gemini and they are quality mounts. The GPD2 served me well till I started autoguiding so I had to go with a heftier mount and went with the G11 to handle the the extra load. A few things I did not like about the GPD2 is the plastic parts, the gear cover kept falling off. I finally had to tape it on and the plastic clutch knobs seemed cheap. The mount also seems louder than the G11 when slewing and tracking but settles down after a few minutes. Also the Starbook seems to go through batteries fast. I had to replace them every 2 to 3 imaging sessions. But other than that the mount performed great. It tracked and autoguided fine, the goto worked fine, and it was easy to transport.

Jeff


PS I would consider selling the GPD2. I only use it for visual and that is not very often.

#7 starbob1

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Posted 13 April 2009 - 06:23 AM

Lowdog'I might be interested in your GPD2'send me a pm.BOB THANKS

#8 Charlie Hein

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Posted 13 April 2009 - 06:51 AM

My requirements are fairly straight-forward:
1. Steady enough to support an 8" SCT or 4~5" refractor
2. Precision manual operation
3. Motorised for sidereal (and ideally lunar & planetary) tracking

(...)

Three questions about the G-11S rig:
1. What is the $425 digital setting circle hardware accessory (and do I need / want it)?
2. Do I need the $125 clutch knob set to switch between manual and motorised operation (like on the Vixen)?
3. Is the G-11 significantly 'better' than the GPD2, and what are there any real pitfalls to the G-11 that I am not taking into account?


1. If your goal is manual star hopping using the mount's setting circles then the DSC hardware isn't really necessary and can always be added at a later date. One thing that I haven't seen mentioned yet is that the manual setting circles on the G-11 are vastly superior to the Vixen's IMO. That are quite large and extremely well made.

2. The clutch knob set is really handy to have. As was mentioned earlier the design of these clutches is very different than the Vixen. The optional knobs make it easier to tighten the clutches down, but if you're pushing the scope around manually it may not be absolutely necessary to have them on day one. You'll likely want the mount to be able to be pushed around at will and you should be able to tighten the clutches up well enough to do this with the stock knobs. Also, if you leave them off at first it makes a really easy birthday or holiday gift suggestion to give to the family... just a thought.

3. The G-11 was originally designed to carry the Celestron 11. It will easily carry your scopes - and will be extremely stable and sturdy with those loads. It is very well made. IMO the build quality is well above the GPDX. I think that if you were to outfit the two identically and take a serious look you should see that the G-11 clearly represents a better value for the dollars spent.

Charlie

#9 ibn ezra

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Posted 13 April 2009 - 08:05 PM

Thanks for all the advice!

The G-11 is a bit more than I had in mind investing when I began entertaining the idea of a second mount, but it's reassuring to hear that the package does what I need right out of the box without the expensive additions.

At this point the idea of investing in a long mount / tripod set-up is an attractive one as it allows me to focus future investments on glass without the necessity of revisiting the mount issue again in the future.

#10 urbanMark

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Posted 14 April 2009 - 01:02 AM

Another thing to consider with the G-11: you can easily purchase any part for this mount from Losmandy and service the mount yourself. Yes, there are higher end mounts, but unless you start mounting really big scopes, or set up a high end remote observatory, the G-11 could be the last mount you ever need.

#11 Mike C

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Posted 15 April 2009 - 02:38 PM

This has been an interesting thread for me, as I've been contemplating a new mount for some time.

I have a very specific question: what is the width of the G-11 tripod legs from foot to foot? If I couldn't take them through my patio doors, that could rule out the G-11!

Thanks.

#12 tidroplane

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Posted 16 April 2009 - 12:15 AM

Mike, the width of the legs fully extended is 47 inches center to center, the tripod legs are attatched at the pier and one can be easily removed if one wanted to try to move this monster thru a door assembled

#13 Mike C

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Posted 16 April 2009 - 05:29 AM

David, thanks for the information. It certainly would have to be disassembled!

Regards.

#14 Mike C

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Posted 18 April 2009 - 04:38 PM

I've always manually guided when imaging with my Super Polaris C8, but would like to move to auto-guiding with a new mount.

Is the GPD2's goto module (i.e. Starbook) necessary as part of an auto-guiding setup? The reason for asking is that the GPD2 with Starbook is actually more expensive (in the UK) than the G11 (without Gemini). The C11 has an auto-guider input on its control panel.

#15 steveeb

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Posted 19 April 2009 - 03:17 PM

You will need some sort of goto controller in order to connect a GPD2 to a computer for auto guiding. Vixen's single and dual drive controllers (SD-1 and DD-1) do not have that ability.

#16 lowdog

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Posted 19 April 2009 - 04:35 PM

You will need the Starbook to autoguide. I use the Orion SSAG with PHD which I connect directly into the Starbook hand controller and it guides fine.

#17 Mike C

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Posted 19 April 2009 - 07:09 PM

Ok. Thanks for the info, Steve and lowdog.






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