Takahashi or Losmandy

[rcheshire]

I have spent a month or more looking at GEM mounts, on the point of ordering, only to change my mind.

Having poured over reviews, technical specs and horror stories, I understand the importance of a good mount for astrophotography.

Some are just too expensive and some cheaper - claiming all sorts of things - I think you get what you pay for.

I'm down to Losmandy or a comparable Takahashi - not a new one? Technically, these two seem to be the pick of the bunch, in the price bracket. Other brands suffer in the following areas. Low resolution gearing, and low resolution steppers, gear and bearing quality, precision and materials, response time when using autoguiding, software compatibility, the use of software for PEC - that is, the mount needs it, otherwise its useless, and so on.

It seems to me that a mount is a long term investment and should have good re-sale value and be scalable - the capacity to increase scope size rather than upgrade the mount for a bigger scope and spend that money toward an imaging camera/accessories. In the meantime enjoy the performance of a quality mount. Digital is fine - goto is nice.

Why is a Tak better than a G-11. Closer inspection of the G-11 specs shows finer gearing in RA, 360 teeth to 144 on the Tak (in comparable price range), and finer resolution steppers.
My only problem with the G-11 is the after sale modification of the precision helical (?), and the stories of having to mod new mounts, removing burrs due to poor machining etc, it seems the Tak is better engineered, but is its performance any better, once you've cleaned up the G-11 - do the later models need that much work, and what mods are necessary.

Still deciding.:shrug:

[gbeal]

Hi Rowland.
this will start a howling war, LOL.
I have a Tak, but either/both will be great. There are pluses for both, and cost comes into it, I would expect the Tak to cost more.
You could/would be happy with either.
Gary

[rally]

Rowland,

For mechanical quaility - backlash, Periodic Error and Tracking precision the Tak wins on quality and reliability - so better for astrophotography.

Although you dont say which Tak - I am assuming either EM200 or NJP with a tight gear set.

For visual and field astronomy using the Gemini Hand controller will make life very easy - Easy star alignment process (presently being minor bugfixed for Southern Hemisphere), No PC required for GoTo and some handy tour and local area identification features.
The Tak on the other hand will need something in addition to the standard hand controller for GoTo (New 3rd party Hand controller just released, PC/Laptop running planetarium software or one of the PDA options)

For Remote use the Tak Temma system suffers from not having a Home position and up until very recently they default to the Northern Hemisphere and have to be powered up with the "S1" Key manually held down on the hand controller to get Southern Hemisphere RA direction !

If you can afford the Tak and a upgraded Hand controller - it will be comparable in ease of use and better in its precision, if not the Losmandy represents good value for money.

Hope that helps
Rally

[Terry B]

Take a look at these pages.
They have error graphs for lots of mounts. The original is in French but hopefully the links have translated the pages.
I think you will find that the tak has much smoother errors.
G11
http://translate.google.com/translate?client=tmpg&hl=en&u=http%3A%2F%2Fdemeautis.christophe .free.fr%2F&langpair=fr|en
EM200
http://translate.google.com/translate?client=tmpg&hl=en&u=http%3A%2F%2Fdemeautis.christophe .free.fr%2F&langpair=fr|en

The list of mounts tested in on this page
http://translate.google.com/translate?client=tmpg&hl=en&u=http%3A%2F%2Fdemeautis.christophe .free.fr%2F&langpair=fr|en

[rcheshire]

Thank you all! Terry, the PEC error data tends to confirm my choices. The G11 needs a precision helical gear and I will need to research that a little more, but otherwise seems a good choice. The TAK is smoother, more sinusoidal - but there is the cost factor.

I was going for portability, but realistically, I think the choice is stability and precision. I can imagine the frustration that is likely to creep in with work-arounds using inferior equipment. So the original advice that I received when first joining the group was sound.

No rush, I'll keep looking. In the meantime, I understand the Losmandy have an after sales mod for the gearing - still makes me laugh. Is anyone else producing precision gears for these mounts - 3rd party vendors?

Edit: Found the following - http://celestialwonders.com/equipment/OvisionVsLHPW.html with a link to the site http://www.ovision.com/Losmandy_PresentationNS_english.htm l

[rogerg]

When I was looking for my Losmandy I was deciding between it and a Tak. I went with the Losmandy because of cost.

One thing that I remember noticing, and which has held true since for me at least, was that in my research I signed up to the Losmandy Yahoo! group and the Tak Yahoo! group... The Losmandy group had lots of discussion about how to improve the mount, what PE error it had, solving problems, etc. In stark contrast, the Tak group only had discussion about pictures taken with the mount, and achievments people had made with the mount, etc. The difference was like night and day.

Now, after having my Losmandy (all be it a GM8 not G11 that you're considering) for something like 4 years I think what I noticed in those groups still holds true, from my perspective too. Losmandy seems to have the capabilty but can be fiddly. Tak "just works". Shame about the price difference (if buying new).

That's my view of it anyhow.

[rogerg]

Oh another factor for me other than Price was that Losmandy had local dealers where as at the time I was looking I couldn't find a local Tak dealer (that I could contact at least).

[rcheshire]

rogerg, good points. Pricing the Losmandy, plus the ovision mod is almost equivalent to the Temma II, but as you point out service is likely to be difficult with a Tak.

It seems that a large part of the Losmandy market are content to accept the production item and amortise the cost of modifications overtime.

[SkyViking]

Sorry if it's slightly off topic but I was of the impression that if you use auto-guiding then mount errors etc won't matter much as the auto-guiding will just keep the guide star centered anyway. Is that a simplistic view?
I have the Losmandy G-11 myself and am very happy with it. However I'm asking because currently I'm not using any form of guiding and haven't used the PEC either. I plan to upgrade to an SBIG ccd cam soon and haven't really given much thought to the whole mount precision issue, sort of anticipating that auto-guiding will solve any problems. Maybe I'm wrong?

[rogerg]

I think this is one of those debates that can go on for ever. Probably best to start a new thread (or, I think there already are plenty if you search the forums for suitable keywords). In short, yes there are reasons you'd want a better rather than worse tracking mount even if you are autoguiding. And then there's just different grades of better :)

[rcheshire]

"...different grades of better..." is probably the notion behind this thread. I'm not sure what I'm buying and want to be sure before I do.

PEC and autoguiding are necessary because it's virtually impossible to eliminate PE. Mechanical precision, complemented by PEC and autoguiding is, in my view, the right order of things. Certainly, before I commit to a purchase.

Sorting out the wheat from the chaff has been the most difficult part.

[telecasterguru]

Rowland,

Another consideration is what are you going to be putting on the mount. There is no point in getting a mount if it won't carry the OTA properly.

I bought my G11 because I wanted the extra carrying capacity of the Losmandy mount. I have a 10"RC weighing in at 16 kilos. With guide scope, cameras, heating etc it is getting closer to 20 kilos.

So the carrying capacity as well as the price was a deciding factor.

I must admit that I was very close to getting a AP1200 but decided it wasn't portable enough to be dragged out every weekend. Would be perfect if I had an observatory but that is a little bit down the track.

Frank

[rcheshire]

Hi Frank. An 80mm triplet refractor 3.5kg's, plus field flattner and 1000D. I would have the same issues. It needs to be sufficiently portable to want to take outside.

As an aside, though not really, this article answers all my understanding telescope mount engineering questions.

http://www.dfmengineering.com/news_telescope_gearing.html#other

[Jeffkop]

Ive owned a G11. It was a great mount. Did everything it was supposed to without any fuss. You will need to take a little time to get used to the Gemini goto system if you go the Losmandy way, but after you get the hang of it you really appreciate its ease of operation and then understand why they did it like this, but believe me, you dont think like that at the start especially if you have used other gotos.
Sorry ... back to the thread. I went the G11 way because the alternatives were way more expensive. I would have really liked to go the NJP or even EM400 way but the $$$$$$ made it too prohibitive. Im positive that owning a TAK mount would be just as pleasurable as owning their telescopes, but I also realize that had I gone the TAK way then I most likely wouldnt have owned a TAK scope.

I have just today taken possession of a Titan50, once again because of the $$$$$$$ involved in going in other well credentialed directions.

This dilemma happens all the time in this game.

So ... having never owned a TAK mount I cant say much about them but their reputation and the voices of others are testimony to their quality.
The G11 however as Ive already suggested, performed fantastically and I seriously recommend it. I used it guided and it worked as advertised so I had no hesitation in going the Losmandy way to the Titan to carry the bigger telescope loads I now require. Of course if money wasnt an issue we would all be equipped with PME's in the observatory, but we all know why that isnt happening.

Good luck and like an early response in the thread suggested ... either way its smiles.

[rcheshire]

Price will be the adjudicator, that's for sure.

Mouth watering stuff the Mesu-mount for a cool 7+k Euro.

www.mesu-optics.nl

[Jeffkop]

Well that could be a winner mount, however I dont know how you'de go about getting one in Oz and Im not certain of what the final landed cost would be but for certain it would add considerably to the $10,600 odd price.

I dont know anything about this mount, it looks very revolutionary and the quoted specs are good but I think you'de be a guinie pig purchaser, just my opinion mind you, and so to some degree you'de be involving risk in the purchase.

As far as service and backup support, I think you'de really be out on a limb in Australia.

Anyway, you sound like you are taking many things into consideration with this purchase so Im most likely telling you nothing new here.

Once again ... Good Luck

[DavidTrap]

I'm not trying to divert this thread to "why don't you by an astro-physics like I did", but will reinforce RogerG's comments. You have to decide if you want to fiddle with your mount, or just use it. My own decision was based on many factors, including the review of the Mach1GTO where they said they forgot they were using the mount and just got on with taking images; and the fact that many people have to "tune" their G-11s to get them working to their satisfaction.

I don't have time to fiddle, I just wanted it to work. If you fall into that category, I suggest you'll end up with the Tak.

DT

[cohiba]

Hi Rowland
I just recivied my G11 last week for my TOA130, i cant fault the mount the machining etc looks first class, but I agree with Jeff the gemini system will take a bit of getting used to after using the Meade for so long

[rcheshire]

There are several more brands out there, at the Tak / AP end of the market, and if I were to buy something of that order I'd go with a friction drive or torque motor / encoder system. These are virtually PE free and guidance systems are all but redundant, absent in some cases.

It seems to me that the 'affordable range' of the market is missing that technology - possibly it is inherently expensive to produce, though I'm not convinced.

Certainly, I don't mean to knock the Losmandy, it is by all accounts a good mount and has served very well. I had hoped to find an alternative technology within the same price range, but it's not available at this time, or so it seems.

Thanks for all your advice.

[Outbackmanyep]

Hi Terry,
The links are great, i just have to laugh at the French translation of "mount" it comes out as "horse" :rofl:

[gbeal]

Ha, explain the to Marc Multiweb, his G11 Horse, LOL.
Sacre Bleu?
Gary

[Terry B]

I think it is a very apt translation. The mount has a saddle on it so what else would you call it other than a horse.:lol:

[adman]

the main difference being that there is a lot more than 10 arcsecs of PE when you put your scope on a horse!:P

[rcheshire]

The modified G11 is definitely the most dependable steed in its class/price range.

So I'm seriously considering a used and cared for modified G11. This is the most expeditious route for now. Alternatively a competitively priced unmodified version - and I will add the Ovision mod.

[Jeffkop]

Before you go and order an Ovision Roland, just use the mount guided and see how it performs. If its 2nd hand it will most likely have had PE correction saved already but you could go thru that exercise too I guess ... My point is you may very well not have to spend any more money than purchasing the mount. Ive looked and cant see anywhere what focal length your going to be using. I guess it must be long to warrant this ovision consideration point blank.

Hope it all comes together for you.

[rcheshire]

Thanks Jeff. That's excellent advice. I will be using an 80mm refractor to start with and work my way up from there.

[rat156]

Hi,

I have a G11 with the Ovision mod. I used Pempro to correct the remaining PE of the mount and it is now <2" p-p, which is what you get from a very high end mount. I image at around 1600 mm FL and find that I still use AO/guiding. I have mounted my 80 mm scope on the mount and used it for AP, the AO takes care of the seeing, but it didn't need guiding. For your setup look at the Ovision and Pempro as an alternative to a guider. If I could properly balance the mount/camera/scope combination (I move things around which upsets the balance a little) and spent a bit more time polar aligning the scope and got rid of the 6" PVC waterpipe pier adapter and used something proper, I probably wouldn't need to guide the 8" RC either as the AO would smooth out the remaining PE.

But, I just tend to use the scope now for AP, so it's just like a Tak now. Cloudfree nights are so rare I don't want to spend them stuffing around with the mount.

Cheers
Stuart

[rcheshire]

Thanks Stuart. 2" peak-to-peak is outstanding. I will have a look at Pempro. I hadn't heard of it until now. Set up is definitely and issue for me also.

Thinking about it, I think the Ovision mod is better applied to a new mount than a used one which has seen wear to the RA gear - maybe just replace it.

[rat156]

Mine was a used mount and still responded well to the Ovision mod.

Cheers
Stuart

[rcheshire]

That's good news, I did wonder about that.

If I haven't driven everyone nuts with my questions. I am thinking of buying the head only - but a horse without legs is not much use - and look around for a heavy duty wooden tripod. Alternatively, steel with 2" legs, or a portable pier - probably make that myself.

[rcheshire]

Just following up, I finished up buying a 10 yo EM 200B at a very very reasonable price. I had almost committed to a Losmandy with the Ovision mod installed, plus newly fitted precision bearings, shipped from the states - then the dollar took a plunge and the cost including shipping just escalated.

GOTO is hand-i-ball:D, but it is a lovely old bit of equipment with tree trunks for tripod legs - I know that I will enjoy using it - couldn't be happier and well within budget. Later this year I will look at argo-navis, they offer a mod for around 1100, which is considerably less than the FS2, but I don't have too many problems finding stuff with an atlas - I'll just have to learn setting circles.

I had intended buying a TMB80SS, but they were on back order and the dollar dropped. I settled on an Explore Scientific 80mm triplet which I bought after careful consideration. It seems to be quite a nice telescope - time and use will tell.

[Peter Ward]

The data there is rather out of date.

Scott Losmandy has been making evolutionary changes to his G-11 for years..and continues to do so.

The current series with bronze worms are very smooth, and even smoother if you go fo the new monolithic bearing housing. Some users have neen reporting +/- 2 arc seconds PE....not bad for a just under 6" gear

[multiweb]

Yep - mine galops in the dark when I'm not watching :eyepop:
On a more serious note I get +/-2.5 arcsec out of the box if I spend a bit of time on the meshing and alignment without PEC. And that's the standard two blocks arrangement. But the one block worm is the way to go because it's very easy to set. Also as Peter pointed out the bronze worms are very smooth.

[rcheshire]

Peter and Marc. It was the price. The G11 is a great mount - I was in the second hand market, and the Tak was too attractive to turn down.

So! IIS members ~ takes deep breath ~ my apologies for my foot in mouth approach to this issue - no offense intended.

Anyway, I took your advice Marc, and got a good mount instead of going for portability, and I'm really looking forward to doing some serious AP. You can put the bit in the horses mouth...