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Alt-az for a big ol' refractor?

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#1 Tim A.

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Posted 17 April 2011 - 05:20 PM

My 6" refractor doesn't get as much use as I'd like, and that's on account of the CG-5GT mount. It's just enough for this big boy, but it is enough. The real issue is that as a rule I don't care for GEMs; too much hoo-hah per ah-ha! AP is not in the picture (pun intended); I'm a purely visual observer and I'd like a fast setup for this lovely cannon.

But with the OTA at 18.5 lbs., most alt-az mounts I've looked at just don't pack it (literally).

The Astro-Tech Voyager is spec'd "up to 20 pounds" (which is pretty much what the CG-5 is spec'd at). But I wonder if it'd really survive at that load.

Anyway, I'm sure I haven't seen everything out there. If anyone knows of an alt-az mount that would carry this big ... I'll go with "big 'ol", though I generally use a more colorful term ... refractor, I'd sure like to hear about it!

#2 mistyridge

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Posted 17 April 2011 - 05:42 PM

The DiscMount DM-6 will carry your yard cannon easily. :grin:

#3 Midnight Dan

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Posted 17 April 2011 - 06:10 PM

too much hoo-hah per ah-ha!


Can't help you, but I'm DEFINITELY stealing this for my list of sayings! :grin:

-Dan

#4 Ira

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Posted 17 April 2011 - 06:18 PM

Get the T-Rex:
http://www.kkohki.co...T-REXmount.html

/Ira

#5 mountain monk

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Posted 17 April 2011 - 06:30 PM

Tim,

I have the DM-6 and love it and certainly think it would handle your cannon. The DiscMount site has lots of photographs showing big, heavy refractors mounted on the DM-6. Like all alt-azs, it is difficult at the zenith. The long, offset handle helps a lot--assuming the tripod does not interfere with it. Peters is a great guy to work with. Expensive? Yes. I don't know of a cheap solution. The T-Rex is also quite expensive.

Dark skies.

mm

#6 Tim A.

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Posted 17 April 2011 - 07:00 PM

I have the DM-6 and love it ... Expensive? Yes. The T-Rex is also quite expensive. I don't know of a cheap solution.

Yeah, I've been noticing that ... :shocked:

I may just have to bear the GEM (literally), until I find a used "mega-altaz".

#7 John Huntley

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Posted 17 April 2011 - 07:35 PM

I use a Giro-type mount for my 6" yard cannon. With a set of vibration suppression pads and CG5 tripod plus 16" pillar it does the job quite well and is simplicity itself to use (sorry it's not a great photo):

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#8 CharlieB

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Posted 17 April 2011 - 08:02 PM

I second the Giro mount. I just picked up a Giro-3 and it comfortably carries my 6" AND 5" refractors at the same time. A great mount!

#9 Jeff Morgan

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Posted 17 April 2011 - 08:32 PM

There are some nicely machined high-dollar alt-az mounts to be had. However, Richard Berry has your answer for a lot less money. The alt-az mount published in his book "Build Your Own Telescope" is designed for a 6" f/15 and very robust.

#10 izar187

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Posted 17 April 2011 - 09:26 PM

Look here perhaps:

http://www.google.co...=UTF-8&oe=UTF-8

#11 george tatsis

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Posted 18 April 2011 - 01:40 AM

I second the Giro mount too. I used to have my 10" Orion Newt mounted on it. In a word ,excellent!!!

George

#12 GlenM

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Posted 18 April 2011 - 10:41 AM

Yes, the Giro III is an excellent mount.

I had one on a Losmandy G11 tripod with a 35lbs OTA on it,no problem.

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#13 Krish Mandal

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Posted 18 April 2011 - 03:10 PM

Glen that is a sweeeeet lookin' scope my friend. I'm not normally a fan of silvery bodies on a telescope but that one is the bees knees!

For those who have recommended the GIRO mount, where in the US is it sold? I only see the EU distributors come up when I Google it.

Thanks.

#14 GlenM

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Posted 18 April 2011 - 03:16 PM

Thanks Krish.

It used to cool down real quick :grin:
Polished Aluminium is the way to go for excellent emissivity.

Not seen any actual dealers in the US for the Giro III,must be one somewhere I suppose.

#15 dscarpa

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Posted 18 April 2011 - 03:18 PM

That scope would be way too much for my Voyager on a Oberwerk tripod, it's very good with WO ZS110. I have my C9.25- it's as heavy as a stock C11- on a Giro with a Sokkia tripod. It's stable, damps well and tracking is easy even at high power. I think the whole rig with shaft, weights, tray ect. was around $750. David

#16 george tatsis

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Posted 18 April 2011 - 03:35 PM

Here you are Krish,

http://www.tech2000astronomy.com/

George

#17 Krish Mandal

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Posted 18 April 2011 - 11:37 PM

George, thanks for the link. I've been there before, but don't know why I never noticed they sell the Giro mount. Maybe because I wasn't actively looking for an alt-az at the time.

'preciate it!

#18 dscarpa

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Posted 19 April 2011 - 09:31 AM

There is a new post here about the Giro 3 no longer being avalable in North America. I got mine from Teton which is MIA. OPT has a Giro clone from Expore Scientific. It goes for $400 with a 2" steel tripod. It looked heavy duty to me. David

#19 Doug Reilly

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Posted 19 April 2011 - 09:43 AM

You might also look at the M7 by Stellarvue or the upcoming Super Half-Hitch...both would handle that on a good tripod. I've used and reviewed the Half-Hitch Mark II and it was superb, the "Super" is designed for bigger scopes. It holds a lot with less brute force than the others. The DM6 would be very nice, too. Tom Peters had a very large refractor on one at NEAF this weekend and it held it very, very nicely. Those are all pricier by far than a GIRO 3 or the ES mount built on the same principles. Don't have any experience with them.

BTW, I think Teton is more KIA than MIA. Mark is thinking about his next steps, last I heard.

#20 jason_milani

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Posted 19 April 2011 - 10:33 AM

I put my 6" achro on a Unistar Deluxe. Handled it just fine using a beefy tripod. Not so well with an Oberwerk surveyor tripod but i think that would be the case with any mount. The Unistar is priced very competitively.

#21 lionel

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Posted 20 April 2011 - 10:43 PM

I just picked up a Unistar Deluxe at NEAF for 20% off. I'm hopeful that it will do the job for my SV130EDT which is 38" long and weighs ~23 lb decked out.

I bought an extra adapter so that the mount can use any of my three tripods including a Celestron with 2" SS legs, a Vixen HAL 130 and an older Meade Standard Field tripod.

I also expect the Unistar will easily carry my Mewlon 250 since Larry displayed a C14 and a Meade 10 mounted together on his dual head Unistar.

Lionel

#22 Krish Mandal

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Posted 21 April 2011 - 10:31 AM

In this same vein, given the choice between a WO EZ Touch and a SV MG2, which is the better mount for something as heavy as an AT90 + AT RACI on one side, and the possibility of an 8" SCT on the other?

I realize saying SCT may get me ejected from here, since the question is about mounting a "big ol' refractor" but I figured an AT90 on one side gets me a pass.

:lol:

#23 Startraffic

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Posted 21 April 2011 - 01:29 PM

Tim,
How about these? http://www.opticcraft.com/ if they aren't big enough then I give up.

StarT. :cool:

#24 Krish Mandal

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Posted 21 April 2011 - 02:00 PM

Those OpticCraft mounts only seem to be EQ, right? They look really hefty ... a bit ugly maybe, but with a neat, industrial sort of charm.

I guess you can configure it to be AltAz but I would think that's too much work. I would guess the reason the OP would want AltAz would be some kind of quick setup as one of the factors.

#25 Doug76

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Posted 21 April 2011 - 03:01 PM

Frankly, were I looking to alt-az mount my C6R, I'd just build a bigger version of this pipe mount I made for my 60mm some time back.
Very strong, quite smooth, and much cheaper!

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