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a choice between gm-8 or az eq6 gt ???

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#1 kbastro

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Posted 20 July 2013 - 07:26 AM

I'm looking for a small portable mount ad narrowed it down to these two,,
I don't care about the AZ mode as I really don't do a lot of visual,,
so many purpose of the mount will be to do light load astrophotography & quick setup,,
BTW which one has the best P.E. of the 2?
GM=8 has Gemini 2
AZ eq6 gt can use eqmod

hmmm choices,,, help me

#2 rmollise

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Posted 20 July 2013 - 08:55 AM

I'm not sure how portable the AZ-EQ-6 is, though it's at least a little moreso than the EQ-6. It would be my choice of these two.

#3 jrbarnett

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Posted 20 July 2013 - 09:24 AM

Neither. GM8, without an upgrade to the G-11 tripod which in turn reduces its portability, is like observing atop spaghetti legs. The AZ EQ6 Pro is new enough not to have the software glitches worked out. Cord wrap is a real problem that has yet to be addressed with a firmware update. You also say that you don't care about AZ mode, so why pay for AZ mode?

I'd go with the EQ6 or Atlas. Better capacity than the standard GM8 and more "ironed out" than the new AZ EQ6 Pro. And less costly than either. I replaced a GM8 with an Atlas. The Atlas is the better mount all around; better capacity, more and better features, lower price, etc. The GM8 looks better due to its all CNC machined nature (that Atlas has some coarse looking castings), but in terms of function and utility, Atlas all the way. The GM8 is a pretty face, but vapid. The Atlas is borderline homely, but solid and true under the skin. :grin:

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#4 rmollise

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Posted 20 July 2013 - 10:11 AM


I'd go with the EQ6 or Atlas. Better capacity than the standard GM8 and more "ironed out" than the new AZ EQ6 Pro. And less costly than either. I replaced a GM8 with an Atlas. The Atlas is the better mount all around; better capacity, more and better features, lower price, etc. The GM8 looks better due to its all CNC machined nature (that Atlas has some coarse looking castings), but in terms of function and utility, Atlas all the way. The GM8 is a pretty face, but vapid. The Atlas is borderline homely, but solid and true under the skin. :grin:

Mi dos centavos.

- Jim


Yep. Right on. Do you want "fancy" or "gets the job done"? I thought I wanted fancy, but five years down the line I'm glad I bought the EQ-6 ;)

#5 astrophile

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Posted 20 July 2013 - 05:13 PM

'Vapid' is strong criticism for a mount that's not sized or designed to do what a 40-45 lb Atlas head does. I agree about the GM 8's stock tripod, but fail to see how an EQ6 meets OP's "small portable" criterion any better than a GM 8 on a G-11 tripod would.

If we're looking for small/portable on a budget, why not a just-discontinued CG5 or an AVX?

#6 telfish

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Posted 20 July 2013 - 05:25 PM

You say you wish to do AP but want portability.

The two tend not to go together! I would go for the Atlas/eq6 and forget the Az side of things.

#7 kbastro

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Posted 20 July 2013 - 06:22 PM

Sorry fellas;
I will NEVER buy a celestron mount any of them,,, I watched the problems my friend had with his cge pro and having to send it back,, and the horror story that is the cgem,,, and am now reading issues with the vx,, my apologies if I insult any C mount owners but this is MHO,,

GM8 is machined well,,, but AZ EQ6 holds more,,, BUT that not a concern to hold a small refractor 80-90mm and guide scope,,
az eq is more modern,,

FYI... I own losmandy and A-Physics mounts and one weighs in at 145 while the other is almost 200# loaded ,, I need a good tracking mount that I can carry from the garage to the yard & toss into the van or my truck and boot down the road for a quickie setup AND so I don't have to put the mount together for 1/2 hour like I do the other 2..

money is not an issue for me,, I just want to make the best choice

SO I have narrowed down the choice to either the az eq6 or gm-8 with Gemini 2,,,

any useful thoughts and critique about either?

anyone here knows what the P.E. is like??? on either??

kb

#8 gezak22

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Posted 20 July 2013 - 07:30 PM

Sorry fellas;
I will NEVER buy a celestron mount any of them ...


I am in the same boat. My CG5 was great, but once it died I knew that dealing with Celestron to get it fixed would only result in me losing time under the stars. I replaced it with a GM8 and I have no regrets.

I am the fourth owner of my GM8 and the foldable tripod was fine for my setup (Tak 90, 50mm guidescope). I only recently purchased the G11 tripod for the windier nights (and in anticipation of upgrading to a Mach1).

As for periodic error, here is an overview. Keep in mind though that when autoguiding, the p2p error is not as important as the slope of the error curve. I would much rather have a PE of 20" if the error is a low frequency sinusoid than a PE of 10" if the error is a high frequency saw-tooth.

#9 Skyshooter

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Posted 21 July 2013 - 12:45 AM

kb,
If it's portability you want in a well made mount I don't think you can go too wrong with the gm8. Even with the stock "spaghetti leg" tripod. I use it retracted and it's been solid. We take it to some pretty rugged country here in the mountains of Utah. It's also nice to know if something mechanical goes wrong I can get parts and fix it myself. I'd like to see that happen with most of the chinese offerings out there. I like gemini 2, it's slews are spot on... nothin' fancy about it.
:p

Ed

#10 gdd

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Posted 21 July 2013 - 08:30 AM

According to the spec sheets the AZ EQ6 GT weighs 2 pounds more than the Atlas EQ-G. The GM-8 weighs about the same as the Sirius. The GM-8 is much more portable. If you need more stability without more weight some of the high end 3rd party tripods could be used.

I have not seen any PE reports for the AZ. The PE for the GM-8 should be twice that of the G-11, the slopes of the error curves should be the same.

Are your current mounts high-end and larger than an Atlas?

Gale

#11 Kendahl

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Posted 21 July 2013 - 09:18 AM

Since the GM8's light tripod appears to be the weak part, how about a GM8 with a tripod from someone other than Losmandy?

Although they are heavier than a GM8, the Astrophysics Mach1 and iOptron iEQ45 are lighter than the EQ6.

#12 EFT

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Posted 21 July 2013 - 12:25 PM

If you don't need Alt/AZ, then don't bother with the AZEQ6. If money is not an issue then there are many high-end options that would really be worth looking at from AP, 10Micron, Takahashi, SB and maybe a couple of others that would give you everything you could want in the way of both a visual and photographic mount in the 40-50 pound portable mount category. If money really is an issue and you won't buy Celestron, then the Atlas/EQ6 or iEQ45 is what you are really looking at.

#13 AndreyYa

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Posted 21 July 2013 - 03:04 PM

Since the GM8's light tripod appears to be the weak part, how about a GM8 with a tripod from someone other than Losmandy?

Although they are heavier than a GM8, the Astrophysics Mach1 and iOptron iEQ45 are lighter than the EQ6.

Agree 100%. I had HEQ-5 and EQ-6 more then 5 years. Now I'm happy with Mach1: it's like real cowboy - it can shoot from any position :) No headache with PE. And it weights less then EQ-6.
With EQ-6, it's a chance to dance a lot with it's unstable PE.

#14 AndreyYa

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Posted 21 July 2013 - 03:04 PM

Since the GM8's light tripod appears to be the weak part, how about a GM8 with a tripod from someone other than Losmandy?

Although they are heavier than a GM8, the Astrophysics Mach1 and iOptron iEQ45 are lighter than the EQ6.

Agree 100%. I had HEQ-5 and EQ-6 more then 5 years. Now I'm happy with Mach1: it's like real cowboy - it can shoot from any position :) No headache with PE. And it weights less then EQ-6.
With EQ-6, it's a chance to dance a lot with it's unstable PE.

#15 kbastro

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Posted 21 July 2013 - 03:16 PM

I thought about the eq6,,, but they seem to have a problem with the latitude adjustment screw/bolts,, This concern was addressed with the release of the az-eq6 which now follows the roots of the q45, AP, and others that switched to the dual side plates for altitude control and stability...

Even my fav mount the (ha ha) cgem has a much better altitude adjustment than the eq6 with its push/pull dual bolt design.

#16 EFT

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Posted 21 July 2013 - 03:40 PM

I thought about the eq6,,, but they seem to have a problem with the latitude adjustment screw/bolts,, This concern was addressed with the release of the az-eq6 which now follows the roots of the q45, AP, and others that switched to the dual side plates for altitude control and stability...

Even my fav mount the (ha ha) cgem has a much better altitude adjustment than the eq6 with its push/pull dual bolt design.


The CGEM actually has the same latitude adjustment design as the Atlas. The difference is that the bolts used are much more robust and easier to grip. In this range of mounts and below, the only ones that I can think of with a significantly different designs are the AZEQ6 and the iEQ45 which uses a design similar to some of the large mounts. Some of the upper tier mounts use worm-type designs in this area.

#17 kbastro

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Posted 21 July 2013 - 06:34 PM

one + for the GM-8 is that it uses the same controller, counter weights and cables that my 145# Titan does,,,
NOW only if AP mach1 used the same counterweights that the 1600 does... one would not have to double up on carrying stuff to a really dark site...

#18 gdd

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Posted 21 July 2013 - 07:06 PM

NOW only if AP mach1 used the same counterweights that the 1600 does... one would not have to double up on carrying stuff to a really dark site...



You're avatar looks like he could handle the double load! :lol:

#19 Tom and Beth

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Posted 22 July 2013 - 02:17 PM

one + for the GM-8 is that it uses the same controller, counter weights and cables that my 145# Titan does,,,
NOW only if AP mach1 used the same counterweights that the 1600 does... one would not have to double up on carrying stuff to a really dark site...


There's an optional Dec Shaft for the Mach1 that uses the same weights as the 900/1200/1600. The shaft was sized to transport inside the mount.

•10.7" x 1.875" diameter Counterweight Shaft (M1053-A)
Price is 90 bucks

#20 Startraffic

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Posted 24 July 2013 - 12:15 PM

kbastro,
I haven't use a G8 I started with a G11 with HD Tripod & DDS. I still have it & it has been upgraded along the way up to Gemini-2 then back down to Gemini-1 when I got my HGM-200. The HGM came with the G-1, so I swapped them over & everything fit & worked on the 1st try on both mounts/
The mount & drives are awesome in comparison to the LXD & GP that I had. The G11 has had the following on it Meade 10"f4 SNT, Celestron C6R, IOptron 90mmf4, and worked well for visual during a solar outreach program. The biggest "problems" with a Losmandy mount is the gearbox & the steel worm. The GB is placed in a bad position and is vulnerable to accidental breakage by being bumped into. (My elbow is just the wrong height & has cost me several.) The good news is they are easily replaceable for $35 & takes (with practice) about 10-15 minutes. The bad news is that they do break. I keep several on hand just in case.
The original worm block system is made of many separate pieces that can be a 3 handed challenge to align and gap properly. The steel worms against an aluminum wormwheels are a bad idea. The solution here is the One Piece Worm block (OPW from Losmandy is $355 with the brass worm) for the RA only. The Dec generally is not a big problem to adjust & the Steel worm can be replaced for $60.
Gemini-2 is no longer a POS. I got my G2 fairly early on & went through the growing pains of a new system under development. Most of the features have been inplemented, & new ones are being regularly added after going through a Beta test group for debugging. Updating the G2 is dead simple. You go to the Gemini2 site, & follow the directions. You can do the update in under 20 minutes without moving the mount You can even disconnect the G2 module & do it inside without anything attached except a computer brick power supply. Part for the G8,G11 are still available for even the earliest of models. The basic design hasn't changed so the new mounts use the same parts as the old ones. New mounts have had Alt locks installed, and an additional bearing installed on the RA. The Bearing was shown to be redundant. A great mount. The HD tripod is built like a tank & will carry far more than the mount itself can.
The HGM's normal rig is an 8" Vixen/Orion R200ss, Celestron C6R; Coranado PST; & IOptron 90mmf4. It tracks with G-2 with a PEC (no guiding) at >2 arc seconds. With guiding (using a Orion DSI-1) through the 90mm it stays with 1-2 pixels. I can't ask for more than that. The last thing you should consider is that if you have a problem, you can pick up the phone & call Losmandy and get a real, intelligent human being on the phone that knows the mounts and can solve the problem without having to send it back for repairs with you paying for shipping both ways plus the cost of repairs. All you really need to work on a Losmandy mount is a good set of allen wrenches, and a good set of feeler gauges.
Yes, I am a fan.
I've never had a Celestron mount so I won't comment about what I don't know about.

Clear Dark Skies
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#21 EFT

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Posted 25 July 2013 - 09:59 AM

I just finished a complete teardown and rebuild of the Atlas Pro AZ/EQ-G mount and wrote up what I found on the EQ6 Yahoo group here: http://tech.groups.y.../message/43087. I was pleasantly surprised by a number of good improvements I found. The basic design is identical to that of the G8/G11 mounts.

#22 jrbarnett

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Posted 25 July 2013 - 03:53 PM

Have you been missing posts about the teething pains with the new AZ EQ6 Pro? Cord wrap issues alone will be a lot more trouble than a potential issue with the azimuth adjustment bolts on the Atlas/EQ6. New stainless steel hand bolts are $11 each and pretty much solve the problem so long as you lightly oil them when threading them into the mount casting. Cord wrap fix? Who knows when...

Also, do you change latitudes often when observing? I adjust my altitude setting twice a year...when I take a dark sky road trip with the mount and then again when I get back home. The altitude bolt issue is easily and cheaply remedied, and affects performance only occasionally if left unaddressed. A firmware graemlin like cord wrap and the myriad of such little demons that plague Gemini II still are problems almost every session. Apples and oranges in headache terms.

Incidentally all Celestron mounts and the Atlas and Atlas AZ EQ6 Pro are made by the same company, Synta, so even if you go Sky-Watcher or Orion, you're still getting a mount made in the same factory by the same workers as those that make Celestron mounts. I'd even take a CGEM over a GM-8 Gemini II or non-Gemini.

- Jim

#23 kbastro

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Posted 26 July 2013 - 11:25 PM

well I couldn't make up mind so I got both mounts,,,
It is clearing out side slowly,,, So I will test the az-6 under a dark sky,,, but earlier daytime slews worked great as I didn't have time to put the g8 together all the way,,, once all done on both mounts I will do a proper run under the no sun,, and compare mounts, PHD graphs, and goto's accuracy and weight handling abilities...
kb

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#24 kbastro

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Posted 27 July 2013 - 03:10 AM

a photo taken tonight with my new AZ-6 of M76
93 seconds unguided 60da iso 1600... 5" apo f/6
using a 2 star alignment and polar axis alignment

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#25 maknewtnut

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Posted 27 July 2013 - 11:07 AM

Since the GM8's light tripod appears to be the weak part, how about a GM8 with a tripod from someone other than Losmandy?

Although they are heavier than a GM8, the Astrophysics Mach1 and iOptron iEQ45 are lighter than the EQ6.


A high quality wooden tripod is THE solution for the GM8 from my experience. I've owned 3 over the years and IMO, doing so makes a very noticeable difference to the manners of this GEM.

Although it's weight and design make it very portable, the Losmandy LW tripod limits one from obtaining the full capability of a GM8 in my opinion. The root cause of issues induced by the stock tripod is that it twists when torque is applied. Less than ideal damping times are a result of this flexure and/or material used (aluminum IIRC).

Over the years I've also offered opinion that the payload rating on the GM8 might be considered liberal when compared to the likes of A-P, Takahashi, and a few others. A great tripod changes that, and makes it's 30lb rating plausible. I support my current GM8 with a Berlebach UNI.

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