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Fork vs. German

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#26 Tom Polakis

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Posted 18 May 2009 - 01:10 PM

I tolerate my GEM but I consider it inferior to a well designed fork mount. You asked for opinions.



Jimmy,

As others have mentioned and you have observed, there are no fork mounts available in the high-end market, unless you go really high-end into something like the picture below.

Since I have no experience with them in an equal amount of years in the hobby as you, I wonder if there would be commercial appeal for a portable, high-end fork mount to support medium to large scopes. Can a fork mount be made that would have comparable weight and portability, and equal stability as today's Paramounts, A-P's, etc.? Could it be made for a similar price? If so, there's a rare, untapped market in amateur astronomy.

Tom

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#27 Charlie Hein

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Posted 18 May 2009 - 01:29 PM

Well, there's always Mathis Instruments if you're looking for either a serious GEM or fork mount...

EDIT: I see where earlier in the thread these were written off the list - not sure why though.

Charlie

#28 Jimmy2K63

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Posted 18 May 2009 - 08:07 PM

I agree with Chris - there is no comparable mount. You asked if there would be a market and my answer would be only if it was built for a few select OTA's because the fork width and tube dimensions dictate the fork itself. You could not build a one size fits all like they can with the GEM's.

Chris I agree with everything you said about buying a mount at that price. The mount is the most critical thing in the whole system, and I certainly appreciate mine because of how it makes it easier to enjoy the hobby. If I can ever afford one in that range I would certainly love one with all the bells and whistles - I'd love to have a high precision computer controlled stable mount system that I could literally mount any OTA on, from the smallest to the largest. I was considering purchasing an Atlas for my Cave (the GoTo version), but would I just be wasting my money? I can get the Astrola mount converted to a GoTo for about $1600 and it is a really decent and solid mount in its own right. Decisions, decisions, I hate em.....

Give me your advice.

#29 Chris Curran

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Posted 18 May 2009 - 09:23 PM

Give me your advice.

I have a 10" f/6 that I also mount to the 1200... I wouldn't want to put it on a smaller mount. I can't imagine an Atlas with a 10" f/5 on it. Visual or imaging use?

#30 Leigh

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Posted 20 May 2009 - 09:33 AM

i'll just add my £0.02 in here..

I just switched my lx90 8" from its forks onto the heq5 pro mount. I was thinking about an eq6 but its quite pricy.
Ok so the forks are convienient.. but the thing that really really got me was the setup time, especially for photography. I don't have an observatory so permenant setup of the OTA isn't really an option.
I came up with crackpot schemes for constructing a weatherproof shell for the scope.. but all in all i was far too scared about leaving the optics out in a small heat attracting container.

The thing I love about the HEQ5 is that you can get it set up, on the pier.. polar/drift and PEC aligned.. and then place a suitable cover over it. All you need to do then is add the OTA via its mount plate and your off.. i'll be using a large flowerpot that is held down by some large bungie cords and a scopecoat under this to keep the mount dry (for the electronics). Every person (shop) that I speak to here in the UK says thats fine to do.

I will also add that i was tearing my hair out over my LX90's inability to track even remotely efficiently. I spent 1 night (last night) with the HEQ5 and i was managing 30-sec subs unguided.. which completely blows me away as all i have ever managed with the LX90GPS prior to its refurb was about 10seconds.

I'd say from my experience.. GEM all the way..

Leigh

#31 CounterWeight

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Posted 20 May 2009 - 11:50 AM

hi Angus,

Buying 'as forked' if your first scope may prove to be all you need for a good while. The autostar is great for helping get to know your sky, and learn what/how your OTA will deliver wrt your expectations. Just dont turn power on if the OTA is 'locked' in the fork :(. You mention getting a wedge, but that isn't mandatory, they work fine without them. The Meade fork mounted AutoStar controlled OTA is made to be an out of the box all in one visual solution.

Is imaging desirable from 'the get go' or a possble long term goal? As mentioned it is 'possible' to image with fork mount, but there's some things to get to know first. And here you'll find the wedge quite useful, but the good one(s) is $$, and pretty heavy, and will make the GEM alternative seem a bit more attractive?. There also used to be field de-rotators, don't know if they are still available. A thing to consider about fork mounts is the can limit what you can attach on the back of the OTA 'fork clearance' wise.

Many folks find the supplied fork mount all they need for visual. Used to be the Meade fork mounts were pretty well made and had all metal gears and etc where it mattered. Worked fine and lasted a long time. Meade sold parts and etc and had great tech / phone support for you to fix when problems came up. I can say that's NOT the the case as of 2003 and later (LX200) and I do not know about the ACF forks... Don't know how that all plays into the picture. It might be good to check support options for whichever you choose. Some folks love the Losmandy brand GEM's for this reason (and others! - but this one specific to repair / support)

I agree to get the best mount you can buy, but, how big is money bucket for purchase(s)? You can easily spend more on a sepirate mount than the scope OTA will cost (even many times the cost), and not worry about being 'mount limited'. My recommendation is that after knowing scope weight, if going with a sepirate mount, get one that has that weight in the middle third of the mounts payload capacity or rating, should be a safe bet.

As Leigh suggests, having a GEM allows some flexibility and ease of use, but that is 'if you need them'. If you decide to get a refractor or try imaging 'down the road', you'll already have a mount (unless you go for a whopper) depending on initial GEM chosen. Most GEM's have a goto capability and nearly all can be equipped with tracking gizmo's.

The good thing is you have a lot of options available - and some will seem more credible costwise once you decide exactly the OTA you want to get, and what you want to do with it in near and long term.

I was a fork mount SCT/MCT visual only astronut for many, many years and was quite happy. Trying imaging changed all that.

#32 Rick Woods

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Posted 20 May 2009 - 04:41 PM

John,

I don't know of anyone making fork mounts that are of the same quality as the top GEM vendors (Tak, AP, Paramount, etc).

Mathis makes a pretty beefy looking fork mount. It's up in the $15-20K range, but since you cite Paramount, etc, it's a valid contender. Personally, I like forks, and if I was to pop the kind of bucks I'd need to for that class of mount, I'd seriously consider the Mathis.

#33 Bowmoreman

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Posted 20 May 2009 - 08:38 PM

As would I...

The aesthetic reminds me of my MI-250 :grin:

Which is a fabulous mount (so far) after only about 4 weeks... My PE is about ~2" near as I can tell (have NOT measured it yet)

But, I sure would LOVE a high quality, mid-weight (say loads to 75# or so) Fork Mount; priced in the $5-8K range... it'd sell like CRAZY!

Why? Because you could put cheap, fast, large aperture Newts on it with NO "chase the EP location on an EQ mount Newt issues!"

(Chiropractors of the world would NOT like it for the same reason)

clear enough skies

#34 nobbygon

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Posted 21 May 2009 - 02:07 AM

Thanks everyone for your help ( especialy Leigh and Counterweight). As stated sevral times, this is a very hard decission to make and I think im going to have to put alot more time into researching the topic. Thanks again.

Cheers, Angus.

#35 Eddgie

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Posted 21 May 2009 - 07:01 AM

While all other responses have focused more on the use of the mount (which I am sure is your primary concern), another factor that you should consider is the WEIGHT if you have to lug this thing around.. If it is in a permanant installation ignore this.

The Meade 8" Fork Mounted scope weights a staggering 73 lbs.
I owned a Celestron NextStar 11 that didn't weigh that much. TO use this, you are going to have to get it on to a polar wedge. If you have sliding counterweigt rails on it, you will most likely have to take all the weights off.

The 10" weighs in at a back breaking 90 lbs. By comparison, my C14 weighs in at 45 lbs.. Of course the Tripod weigs 40 lbs (Similar to the Meade) but I also have counterweigts (which you might need with the Meade, but mine are 50 lbs) and the EQ Head (you will need a hefty wedge).

This isn't a "Meade/Celestron" comparison. I am simply saying that these fork mounted scopes are really bulky, unwieldy packages. If you are going to Alt-az mount them, they can be more manageable, but if you are transporting them, or attempting to get them up on a wedge, they can be monsters.

I think THIS is why the GEM is popular. It simply is more manageable per inch of aperture. For the forks to be acceptable, they have to be as massive as the telescope or you get springyness.

And if you are talking about an aftermarket mount, then consider that you may have to actually remove the OTA from the fork to move it.

Again, if it is observatory, I would go with the fork. But if you have to move or transport this thing, think about the weight.

I have heard of SEVERAL people that let go of their big Meades because they simply couldn't manage them.. Loved the scopes, but simply found it to daunting to set them up.

Good luck with your decision.

#36 jrcrilly

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Posted 21 May 2009 - 07:29 AM

The Meade 8" Fork Mounted scope weights a staggering 73 lbs.
I owned a Celestron NextStar 11 that didn't weigh that much. TO use this, you are going to have to get it on to a polar wedge. If you have sliding counterweigt rails on it, you will most likely have to take all the weights off.

The 10" weighs in at a back breaking 90 lbs.


The stated weights include the tripod - which does not get mounted to a wedge. Actual tube/fork weights are about 45 pounds for the 8", 62 pounds for the 10", and 82 pounds for the 12".

#37 Jimmy2K63

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Posted 21 May 2009 - 07:57 AM

Give me your advice.

I have a 10" f/6 that I also mount to the 1200... I wouldn't want to put it on a smaller mount. I can't imagine an Atlas with a 10" f/5 on it. Visual or imaging use?


I will be doing both. I have done lots of astrophotography with the Astrola GE mount and its a fine mount, just dated, so I guess I'll just have to look into getting it converted to a GoTo if that's what I want. I can't believe a $1500 mount isn't built solid enough to hold that telescope properly. But if I spend $1500 on the conversion I can probably hang two scopes off of it.

I posted a photo of the scope in it's observatory over in the observatory forum last evening if you want to see what used to be my setup.

#38 Eddgie

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Posted 21 May 2009 - 09:31 AM

Ah. My mistake... Meade web site listed the weights of the "Telescope" and I did not realise that this inculded Tripod weight.

#39 Rick Woods

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Posted 21 May 2009 - 09:50 AM

This isn't a "Meade/Celestron" comparison.

Actually it is, sort of. Meade assemblies are considerably heavier than Celestron ones right down the line.

#40 Chris Curran

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Posted 21 May 2009 - 07:18 PM

I can't believe a $1500 mount isn't built solid enough to hold that telescope properly.


:roflmao: Depending on your tolerance, most any mount will work or visual use. Imaging - that's a whole different bucket of worms and $1500 isn't going to do it for a 10" newt.

#41 Jimmy2K63

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Posted 24 May 2009 - 01:21 PM

Chris is absolutely right about the quality of the mount. A lousy scope on a good mount will outperform a good scope on a lousy mount. I'm just astounded how much money a good quality mount is today, it makes me appreciate mine even more.

Now if anyone has any creative plans and/or images of some good homemade tangent arms for a GEM I would like to see some. I'm sure there are tons of cars out there in wrecking yards with suitable power window motors to drive the dec axis. :bow: :grin:






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