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GHarris
super member


Reged: 06/06/09

6 inch refractor (visual) - which mount?
      #5653748 - 01/31/13 07:39 AM

Hi folks,

What is the lightest equatorial mount you would feel comfortable using a 6 inch f/8 refractor on, purely for visual use? The refractor I have in mind is the relatively lightweight (for its size) new 152/1200ED from APM. But light tube weight might not count for much given the length of the refractor (I fear).

From what I've googled so far it seems like a HEQ5/GM-8 class mount, even with upgraded tripod legs and other tweaks, isn't quite enough, while something like the Atlas/EQ6/G-11 is certainly enough but is also very bulky and heavy. Is there an in-between option? I wish there was but can't seem to find one. And I can understand there not being one, since "6 inch f/8 refractor for visual use only" must be a small niche compared to all the imagers with different types and sizes of telescope which presumably fit the available mount size classes well.

Most of the time when I google to find discussions of all of these mounts I end up seeing discussion on mounting SCTs or smaller refractors for imaging. For purely visual use, for a large refractor, there is some discussion but not a whole lot. I have seen talk of some people using a TEC 140 on a Losmandy GM-8, for example, with differing opinions on how viable it is. At the very least the consensus was that you'd either want to replace the GM-8 tripod legs with G-11 legs or leave the GM-8 legs retracted and use an extension pier. Anyhow - while the TEC 140 is about the same weight (this new doublet is quite light for its size) it isn't as long, which is what will really affect stability I think.

I hope to use the refractor for outreach. The (relative) portability of the mount will have some bearing on how practical and easy it is for me to set up the scope in various places. But if the scope isn't held steadily enough, it doesn't matter where it is!

I understand that this is all a bit subjective, since it depends on each person's definition of "good enough". But I'd appreciate any views the forum can offer. I'm also aware that it's a bit absurd to think about portability, in any sense, when dealing with a 6 inch refractor!

EDIT: Thought I should add that I would probably use powers up to/around 250x at best, and perhaps more commonly 200x. I'm in the UK so it's rare to get great seeing.

(I wasn't sure whether to post this topic in the Mounts section or the Refractors section, so I don't mind if mods wish to move it)


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Mirzam
Post Laureate
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Reged: 04/01/08

Loc: Lovettsville, VA
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5653772 - 01/31/13 08:07 AM

You are analyzing the situation correctly, I think. I sometimes use my GM-8 to carry my RV-6 (f/8 newt), which has an OTA weight of only 8 lbs. This combo works well. For my 5" f/12 D&G I use a G-11 and this works well for visual.

The G-11 is a bit more effort to deal with, but not that different from the GM-8. Unless you want to build your own Berry alt-az mount, I think you will just have to accept the set-up tear-down hassle of the G-11.

Here's a real nice Berry mount

I use a 12" extension on my G-11 tripod to get the rear end of the scope up to a convenient viewing height. Pretty much a required item.

JimC


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Jeff B
Carpal Tunnel
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Reged: 12/30/06

Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5654363 - 01/31/13 01:46 PM

I've used my APM 152 F8 triplet (which weighs considerably more than the new doublet)on my GM8 for visual use with some success and my 6" F10 Istar doublet with even better results. However, the limiting feature for both vibration and eyepiece height when pointed at zenith for both scopes is the stock tripod. Putting the GM8 on my G11's HD tripod greatly reduced those limitations. My G11 is much prefered though, especially with the Gemini. In fact the G11 does a great job with my APM 175 F8, which weighs considerably more than my 152MM f8 triplet.

Jeff


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Mike Clemens
Frozen to Eyepiece
*****

Reged: 11/26/05

Loc: Alaska, USA
Re: 6 inch refractor (visual) - which mount? new [Re: Jeff B]
      #5654716 - 01/31/13 05:14 PM

Ed Ting said about a 155 f/7 on a GM8

"the OTA weighs in at 23 lbs, and will
just barely work for visual use on a GM-8 (for photography, get something
bigger.)"

If you are into high magnification binoviewing, I think, get something bigger. (G11)

I think a 6" refractor is ENTIRELY easily portable. It's the mount that kills ya. So if you can get by with the GM8 then you will have an easily portable kit.


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SteveG
Post Laureate
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Reged: 09/27/06

Loc: Seattle, WA
Re: 6 inch refractor (visual) - which mount? new [Re: Mike Clemens]
      #5654803 - 01/31/13 06:05 PM

You are looking at the same scope I want to buy, and my plan is to use it on an IEQ45 with a surveyors tripod or possibly the Ioptron pier.

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Pat at home
sage


Reged: 03/16/07

Loc: Campbellton, New Brunswick, Ca...
Re: 6 inch refractor (visual) - which mount? new [Re: SteveG]
      #5654840 - 01/31/13 06:23 PM Attachment (123 downloads)

You don't mention if you want a manual or a motorized mount. Also, do you prefer ALT/AZM or EQM?

I own a 6" inch refractor and it is heavy once a finder, a diagonal and an eyepiece are added. I mount it on an EQ6 (Atlas) for when I want GOTO but I don't carry that very far. When I use that scope to cruise the Milky Way or take it camping I mount it on a manual ALT/AZM mount called a Duo-T purchased from Canadian Telescopes. The same mount is available as the Sky-Tee II from Skywatcher.

Here is a photo of that mount and scope sitting on a wooden surveyor's tripod. This handles the load quite well.

Edited by Pat at home (01/31/13 06:25 PM)


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k5apl
scholastic sledgehammer
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Reged: 05/19/06

Loc: Arkansas
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5655230 - 01/31/13 10:40 PM Attachment (69 downloads)

I have a 6 inch f7 refractor..my Experience has been to use
either of these mounts:
EQ G11 Losmandy with extension
Alt-Az DM6 DiscMounts with extension

Both are relatively lightweight. Ideal EQ mount is an AP900
or AP1200, etc. Others can chime in on the Chinese mounts.
I recommend that you go more toward the 'stable' direction
than the 'lightweight' direction. you will not be happy
with an undersized lightweight mount, I predict. As always,
we either have to pay the price, or be talented enough to make our own mounts.
BTW I disliked the Gemini I on my G11 until I got a polar
alignment scope, And really like the SkyCommander on my
DM6 that I use as my main mount.
I used the Losmandy G11 tripod, but now use the Meade Heavy
Duty Tripod. No shakes or shimmys with binoviewers. Both are
very stable.
This is my opinion. Good success,
Wes


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Traveler
Pooh-Bah


Reged: 08/19/07

Loc: The Netherlands
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5655498 - 02/01/13 02:23 AM

The new APM refractor is the one i also want to buy. Not now but in the near future. The mount i will use is the AP 400 mount. I know several people use this mount with the Tec 140.
Ed Ting used this mount with an AP 155 starfire Apo. He said about this combination:

"The AP400 is designed to carry 4" and 5" refractors, but it turned out to be just fine for the 6" as well, even at high powers." For the whole story click this link.

I gues that i can use the new APM refractor with my Giro III mount as well.
In both situations i use the Baader Hardwood tripod, which were sold by Astro-Physics.

Edited by Traveler (02/01/13 02:24 AM)


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GHarris
super member


Reged: 06/06/09

Re: 6 inch refractor (visual) - which mount? new [Re: Traveler]
      #5655528 - 02/01/13 03:18 AM

Thanks for all this advice.

Pat is right, I should have given some more information in my first post. I'm a Dob user currently and I will sometimes be using this new refractor for outreach. For outreach I think it is very helpful to have tracking so that I don't need to keep interrupting people's viewing to re-centre the object or confuse them by trying to coach them into tracking it themselves.

I only actually want tracking, though, I don't feel any need for GOTO. As I said, I have used Dobsonians up to now and I am happy to manually find objects, in fact I think I even enjoy it. The market seems to be aimed towards goto mounts that optionally have less goto-ness for a discount, though. A well made, less complex but mechanically sound mount that would track in one axis is all I'd want but that's wishful thinking I expect.

There's also some convenience for myself, when doing lunar or planetary viewing, of tracking but I don't consider it as much of a necessity there. Sometimes I might like alt-az.

I'm not at all interested in astrophotography and don't anticipate that changing.

But I had basically assumed that I'd "need" a substantial EQ mount of some kind to get decent tracking. I suppose I should look into whether alt-az mounts can track acceptably for pure visual use. Not needing a load of counterweights etc would be more convenient, but I suppose balancing the scope (front end to back end when changing eyepieces etc) might be more fussy?


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k5apl
scholastic sledgehammer
*****

Reged: 05/19/06

Loc: Arkansas
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5656145 - 02/01/13 11:09 AM

Hi again,
You have a wise idea for tracking with an Outreach telescope. My recommendation is still the G11, but now
without GoTo. Much cheaper, and DSC's can be added later
if needed.
If not the G11, then choose a substantial mount. The long
tube length of your refractor is going to be less stable than a short tube telescope. I have had an AP400 with 5 inch
refractors, and it was at the end of its capability in my
opinion (for my use). No way my 6 inch f7 would be to my
liking with its extra weight and length.
And around here at Outreach the tendency of new viewers is
to grab the telescope, for stability or reference to the eyepiece. Another reaso to have a more substantial mount.
I recommend not skimping on the mount; in my case I have
done it and lost money when upgrading to something better.
My motto now is : Get it right the first time. Hopefully
ZI can follow my own advice.
Wes


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WillCarney
Pooh-Bah
*****

Reged: 10/08/09

Loc: Bloomington, ILL
Re: 6 inch refractor (visual) - which mount? new [Re: k5apl]
      #5656210 - 02/01/13 11:53 AM


I generally have a 60, 70, 80 or 90 mounted on top of my six inch refractor. This allows me to move the scope forward so it won't hit the tripod on my Atlas. The picture above is using a QSI but in that case I made sure not to get close to the tripod. Generally I don't need the extender on the tripod so don't use it. The atlas works just fine with my 6" f/8 Celestron. I do put four pounds of excercise weights around each leg at the bottom to help with some stability. You notice I have a losmandy on top and bottom. This prevents some tube flex I had with the smaller bars. This complete arrange works well for me.


Here with a multiple plate I can attach three refractors.

I sometimes also mount my C-8 on my Atlas with a ST-80 on top of it. All depends what I want to do. The Atlas is a good mount.

If you get one convert it to the losmandy size plate if it does not come that way. Also the scope. This is much more rigid than the vixen size.
William


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GHarris
super member


Reged: 06/06/09

Re: 6 inch refractor (visual) - which mount? new [Re: WillCarney]
      #5662138 - 02/04/13 05:10 PM

SteveG, thanks for the suggestion of the IEQ45. From what I've read so far it might be exactly the kind of in-between option I was looking for. Well, the nearest match at least - I can't honestly expect the market to cater for my wish for a tracking-only, non-goto telescope that's ALSO the right weight. Between the IEQ45 and the G11, the former being a nice weight and the latter having the option of tracking only, I'd probably go for the IEQ45. I will keep reading up on things because I have plenty of time before the scope is delivered.

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jrcrillyAdministrator
Refractor wienie no more
*****

Reged: 04/30/03

Loc: NE Ohio
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5662179 - 02/04/13 05:33 PM

If you want tracking only at that OTA weight, an original Atlas (before goto) would be both perfect and inexpensive. Maybe $500-$600?

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Kendahl
member


Reged: 02/02/13

Re: 6 inch refractor (visual) - which mount? new [Re: jrcrilly]
      #5662275 - 02/04/13 06:37 PM

Like you, I am searching for an astrophotography mount with a reasonable load capacity that won't break my back. I thought the iEQ45 might be the answer but some comments on Yahoo's ieq45imaging group (http://tech.groups.yahoo.com/group/ieq45imaging/message/1775) have me thinking again. Personally, I can't handle the weight of an Atlas or CGEM. A G11 would be a stretch. If you can handle such weights, an Atlas would be a safe bet.

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Messyone
professor emeritus


Reged: 05/02/12

Loc: Down Under
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5662383 - 02/04/13 07:55 PM

Whatever you get mount wise get an electric focuser too. I have my 6" f8 on an HEQ5 basic (non goto) mount, which I'm about to make a wooden ash tripod for. The scope slews around nicely on the HEQ5. As far as I can tell the SS tripod extension part of the legs is the problem, the scope doesn't wobble when the legs are retracted but it's all too close to the ground if they are in. The scope needs careful balancing, a sliding weight from Crawmach might help a bit. Total weight of OTA finder etc is 11.5 kg.
Matt


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GHarris
super member


Reged: 06/06/09

Re: 6 inch refractor (visual) - which mount? new [Re: Messyone]
      #5664778 - 02/06/13 08:13 AM

I didn't know the Atlas mounts had ever been offered without GOTO. It's interesting, and saves money, but I'm still concerned about the weight of EQ6 mounts. That's the real issue for me. I don't mind spending a bit more money if the mount is both stable enough and relatively light. Atlas mounts just seem too heavy.

Kendahl, I begin to see what you mean. Not long after my previous post I began to stumble onto occasional mention of the IEQ45 oscillating in RA when used with even a TEC 140 because of tube length. I'll provide links this evening if I can scrounge them up again. It's hard to quantify just what people mean, and how bad it is (for visual especially), when reading these isolated posts which don't tend to provide context with a detailed comparison to other mounts. I mean, it might still be better than a HEQ5... could it really be worse? I'd like to believe that the iEQ45 would work, because it looked ideal up to now.

I'd also like to believe that a HEQ5 would work with the right tripod legs but I just don't know if I should risk disappointment. Messyone, I'm guessing you recommend a motorised focuser because it allows focus control to be done with a handset... and that that's desirable because when you actually touch the OTA to focus manually, on a HEQ5, it vibrates a lot. Hope you can tell me I'm wrong! "Stable enough" is subjective and I don't know how to judge if we're on the same wavelength.

In the pipe-dream category there's a fantastic mount being made in Denmark:

http://www.trackthestars.com/what-we-make/tts-160-panther

Ticks all the boxes and then some. But I think I have to accept that it's completely out of my price range. Beautiful though. I honestly didn't think I'd find a mount that was suitable but too expensive. I thought it was usually a matter of "massively stable, massively expensive, massively heavy" in the high end bracket.

Edited by GHarris (02/06/13 08:18 AM)


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Eddgie
Postmaster
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Reged: 02/01/06

Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5664806 - 02/06/13 08:43 AM

Over the last decade that when it comes to mounts, I have learned by experience that what one person finds completly reasonable, another will find completely unreasonable.

Be careful.

My 6" APO rides on my biggest, heaviest mount, a Meade LXD-750, and there is no doubt to me that it is the right mount for the telescope.

It is far better than the Atlas, and even better than the CGE.

But this is me.

There are two issues with a refractor. The first is the lenght of the OTA. To get the eyepeice high enough to be able to reach at zenith without sitting on the ground, you have to raise the legs to the maximum (and that may not always be enough) or add a pier (which adds weight).

The second is that the long tube will take longer to settle once it starts moving.

I initially was OK with the Atlas, but in time, I realized that it was not the best choice for a 6" refractor for anything be relatively low power observing.

But so many people want to use very high powers... If you are one of them, you will quickly tire of the Atlas. Every time you touch the focuser, you will get a long period vibration. This was the problem with the Atlas for me. To keep from sitting on the ground, I had the legs fully extended, but this cause the tripod to vibrate more easily.

If you feel that most of your observing will be done at powers below 100x, an Atlas may be fine for you.

But if you plan on doing any serious planetary observing, I would go heavier. Even a very light breeze can induce oscillation when using the Atlas/6" scope when you have the tripod fully extended.

If you have not already settled on the scope choice and the weight of the mount is a crucial issue for you, my advice would be to move to a TEC 140 or other slightly smaller scope.

These will be more at home on an Atlas and will offer a better viewing position (though you still may find yourself sitting on the ground when viewing close to zenith). The reason for this is that if you keep the tripod higher so you can view more easily near zenith, once you go lower in the sky, you wind up sometimes having to stand up. This is because the eyepeice on a big refractor moves though a far larger arc with respect to the head than with other scopes. With a C14, I can do most of my observing seated. With my 6" APO, I find myself standing sometimes, or sitting almost on the ground other times.

Think about your observing. If it is weighted more to higher powers, get a heavier mount.

Otherwise, get a shorter lighter telescope and a less heavy mount.

Good luck.


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Pat at home
sage


Reged: 03/16/07

Loc: Campbellton, New Brunswick, Ca...
Re: 6 inch refractor (visual) - which mount? new [Re: Eddgie]
      #5665168 - 02/06/13 12:38 PM Attachment (64 downloads)

Quote:


I initially was OK with the Atlas, but in time, I realized that it was not the best choice for a 6" refractor for anything be relatively low power observing.

But so many people want to use very high powers... If you are one of them, you will quickly tire of the Atlas. Every time you touch the focuser, you will get a long period vibration. This was the problem with the Atlas for me. To keep from sitting on the ground, I had the legs fully extended, but this cause the tripod to vibrate more easily.

If you feel that most of your observing will be done at powers below 100x, an Atlas may be fine for you.

But if you plan on doing any serious planetary observing, I would go heavier. Even a very light breeze can induce oscillation when using the Atlas/6" scope when you have the tripod fully extended.






I've had similar experience with my EQ-6 when I acquired an AR152. At the lowest position of the tripod the height of the EP meant sitting on the ground when viewing at higher elevation angles. But when extending the legs to a comfortable height the stability became a serious issue for me at least. I do not like having to wait 3 or 4 seconds every time I touch the focuser.

I read and researched for a while and started thinking that maybe the mount was adequate but the tripod was not up to the task. So before jumping to the next class mount with the attached much higher price tag (the money supply is not unlimited at our house) I looked at beefier tripods since a permanent pier is not in the cards just yet. An observatory is planned for the future. The heavy duty tripods, although more economically achievable than a beefier mount, are not being given away in cracker jack boxes.

So before committing hundreds to a tripod I tried my hand a designing a rigid structure to hold my EQ6-pro with AR152. That scope weighs 27 lbs with diagonal, eyepiece and finder. There is no scope movement when focusing and an accidental light tap on the scope does make it oscillate but only two cycles and is static again in less than 2 seconds. (I got 1001 but did not finish 1002).

Here is photo of what I came up with. Not very pretty but it is a prototype. At zenith the EP is 30 inches from the ground, while maximum height of the EP is 61 inches before dipping below the horizon. 30 inches is comfortable on my LYBAR.

I have other photos of this mount and tripod and also of this tripod with the AR152 on a Duo-T mount. Now that is a rock solid combination, even more so than the EQ6.


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GHarris
super member


Reged: 06/06/09

Re: 6 inch refractor (visual) - which mount? new [Re: Pat at home]
      #5730718 - 03/13/13 05:07 PM

This thread really was very helpful to me and I'm finally beginning to settle on the following opinions after much dithering.

- Losmandy G11
What stands out about this mount, for me, is its build quality, clutchless manual movement that doesn't knacker subsequent tracking, and the low power use of the non-GOTO model as discussed here:
http://www.cloudynights.com/item.php?item_id=2030
Lugging power tanks around is a small nuisance and if I could get away with only using a relatively small power tank that would be a bonus. I honestly don't think I need GOTO. If the mount I end up choosing has it, that's all well and good and I'll probably make some use of it. But I don't place any real value on it. I don't mind finding stuff myself.
However the G11 is pretty expensive and the weight of it (17kg?) is a bit beyond what I think I can be comfortable with. As far as I can guess without actually buying one!

- Skywatcher AZ-EQ6 GT
This has a lower weight than the rest of the mounts in this capacity class - I've read comments that it feels a fair bit lighter than the quoted specs' weight difference between it and the standard EQ6. I was looking for something with good stability while still giving some kind of nod towards portability (If the iOptron IEQ45 actually "worked" for long OTAs I might still be interested in it). This seems to be the best compromise I can find, with its token weight reduction.
I like the relative simplicity of an alt-az mount that tracks (this is for visual use, and polar alignment is an extra step in EQ mode). I have no immediate plans to use a 2nd scope in alt-az mode though there's no harm in having the option.
But I expect I'll need a substantial battery. On the bright side, this is a separable unit from the other things I'll have to carry to and fro. I don't mind quite so much as long as no one component of the setup is too heavy on its own.

- HEQ5
I'd be absolutely delighted if I bought it and found it acceptably stable. At times I entertain the notion of just buying the cheapest non-goto model to try it out. I'd definitely want to replace the tripod legs. Perhaps one strategy would be to buy the HEQ5, and then sell it on if I don't like it and get the AZ-EQ6 instead. And pick a good enough tripod to use with either. Probably a slightly mad strategy given the amount of money it involves throwing around on the off-chance.

One detail I am wondering about is eyepiece height. Fully extending the tripod isn't ideal for stability as I understand it, though if it's necessary for usable ergonomics then that's that. I'm considering alternatives like the Berlebach Planet as a tripod upgrade but they still generally come to about the same kind of height ranges. I might get the Skywatcher EQ6 extension tube, which would add about 20cm. Not sure if that would be adequate. Oddly my first impression is that there seem to be longer pillar extensions available for the HEQ5 than for the EQ6 (in the UK). If I were to use an EQ6 with its legs retracted to minimum and with the 8 inch pier extension, some quick clumsy maths (my favourite kind, as you may have begun to notice) suggests a dovetail height of about 140cm and therefore an eyepiece height of about 80cm. Which isn't much. I have a fairly adjustable observing chair but even at its lowest setting the length of my own torso means the eyepiece would still be too low.

Anyhow I am inclined to think that the AZ-EQ6 is the one to go for, and that I just need to pick an appropriate tripod and extension (haven't done enough looking for them yet). I presume that I can't buy the EQ6 without the stock tripod to save money, regardless of my intention not to the stock tripod, which is a shame but there we go.


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Eddgie
Postmaster
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Reged: 02/01/06

Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5730743 - 03/13/13 05:29 PM

I should have mentioned this in my earlier post.

When I had the Atlas, I did to one modification that made a very distinct improvement. Worth doing in my opinion.

The vibration in the Atlas when fully extended is what I call "Guitar String" vibration of the legs.

The EQ6 spreader rids very high in the apex of the mount legs. This means that when fully extened, you have about 5 foot of tubing that can start to vibrate.

I thought I could improve the performance by using a different spreader.

I had an old spreader from a Celestron Ci-700 ( which I might mention would be a fantastic mount for your scope because they sell so inexpensivly used )

The Celestron spreader was about 3 inches or so more across than the metal spreader that came on the scope.

I bought a threaded rod and cut it to a length that would allow the new spreader to be attached (I think I had to buy a threaded knob from McMaster Carr).

This spreader sat about 3 inche lower, but I noticed a definite improvement.

Later, I saw someone else that had taken a similar approach but cut a ne spreader from plywood and (and cut holes for eyepieces). his spreader sat even lower, and he said it make a big differnce.

This tells me that if you are handy, you may be able to craft a new spreader that could inprove the stability.

I think trying to improve the rigidity of the tripod is a better approach.

I used a Semi-pier on a Vixen GP once to try to improve the same condition, but I did not a the end of the day feel that it was worth it. A bit of improvment but at a big cost in weight.

Always a tradeoff.


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Eddgie
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Reged: 02/01/06

Re: 6 inch refractor (visual) - which mount? new [Re: Pat at home]
      #5730752 - 03/13/13 05:34 PM

Very... Cool

I have though many times about makeing a "Truss" style pier for my refractor mount. The tripod legs on my LXD must weigh 60 lbs. Even retracted the leg are almost 4 feet long to the top of the tripod mounting plate.

I thought it might be possible to make an open truss, light weight pier.

I don't use the 6" APO that much though so it is a very low priority thing for me to try to change.

But I love your tripod. It shows cool ingenuity.


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herrointment
Post Laureate
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Reged: 03/12/11

Loc: North of Hwy. 64
Re: 6 inch refractor (visual) - which mount? new [Re: Eddgie]
      #5731409 - 03/13/13 11:54 PM Attachment (68 downloads)

I built "Parker style" tripod and put a wood tubed extension on it. The extension is braced by 6 5/16" threaded rods that are hiding in the copper tubes....the center bar of the mount extends down to the base of the extension.

The tripod design is dead solid and the extension actually worked. I know a Sky View Pro mount shouldn't work very well
with my shortened C150.....but it does!

I thought I'd add another homemade option to your mix and show off a bit too!

Had it out tonight.....

Edited by herrointment (03/13/13 11:57 PM)


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hottr6
Carpal Tunnel
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Reged: 06/28/09

Loc: 7,500', Magdalena Mtns, NM
Re: 6 inch refractor (visual) - which mount? new [Re: herrointment]
      #5731783 - 03/14/13 08:45 AM

The car tracks on either side of your rig remind me of the classic cartoon image of a pair of ski tracks going around opposite sides of a tree!

Shane in gray-zone NM


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Startraffic
professor emeritus
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Reged: 02/12/06

Loc: Lat. 39.143345, Long. -77.1748...
Re: 6 inch refractor (visual) - which mount? new [Re: GHarris]
      #5731793 - 03/14/13 08:53 AM

GHarris,
I had a Celestron C6R (6"f8) on my G11 for a couple of years & loved it. A great combo. When I got an 8ft Dome I had a problem with clearance in some places with only 1-2" between the EP & the wall. I haven't used a CGEM or Atlas so I can't comment on them but the G11 with the digital drive system is a good fit that will allow for growth later on in capacity & control. I've hung a 10"f4SNT, the C6R & a 90mm GS on mine for visual solar outreach. Total load was ~#45. The only thing different I did was slow the slew speed down.

Clear Dark Skies
Startraffic
39.138274 -77.168898


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northernontario
Pooh-Bah
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Reged: 07/01/09

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Re: 6 inch refractor (visual) - which mount? new [Re: Startraffic]
      #5731811 - 03/14/13 09:02 AM

I use an older HEQ5 (non go-to) with a meade heavy duty tripod for my Canadian Telescopes 152 mm refractor. The scope is about 25 pounds.

Works very well, stable, solid, quiets down quickly.

jake


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Eddgie
Postmaster
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Reged: 02/01/06

Re: 6 inch refractor (visual) - which mount? new [Re: herrointment]
      #5731837 - 03/14/13 09:22 AM

I love it..

Kind of a "Steam Punk" look. I totally love it.

As I mentioned, I have considered making a wood tripod or pier for my LXD 750 from time to time and I find your work to be quite inspiring. I am going to have to dust off my drawing equipment.

Thanks for sharing. It is a beautiful design.


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mlanglois
member


Reged: 12/04/09

Loc: Newton, MA
Re: 6 inch refractor (visual) - which mount? new [Re: herrointment]
      #5732277 - 03/14/13 01:38 PM

Herrointment,

That is one of the most esthetically pleasing tripods I've ever seen... truly fine furniture quality. Great Job

Michael


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Kunama
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Reged: 10/22/12

Re: 6 inch refractor (visual) - which mount? new [Re: mlanglois]
      #5732550 - 03/14/13 04:47 PM

Quote:

Herrointment,

That is one of the most esthetically pleasing tripods I've ever seen... truly fine furniture quality. Great Job

Michael




Beautiful skills on show right there Jim !!! One of very few astronomy DIY items that made me stop and study it. You can rightly 'show off' a bit.

As for the original question re mounts:
I am going to use my 5" Tak purely as a visual scope for a while and for visual nothing beats an Alt-Azi mount for convenience. I am going with the T-Rex with Wildcard Innovations Argo Navis.


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HCR32
sage


Reged: 08/27/10

Loc: Australia
Re: 6 inch refractor (visual) - which mount? new [Re: Kunama]
      #5732598 - 03/14/13 05:21 PM

I wasn't happy with my 5" on an eq6. The problem is the length of the refractor. At 1200 you'll have settle down time issues. G11 would be a minimum for me.

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urbanMark
sage


Reged: 07/08/06

Loc: San Jose, CA
Re: 6 inch refractor (visual) - which mount? new [Re: HCR32]
      #5737015 - 03/16/13 07:40 PM Attachment (20 downloads)

I've been quite happy with my 152ED mounted on a G-11 w/ Losmandy tripod and pier extension. For visual use it is great, and it is a magnet during outreach. A long scope on a tall mount is like a beacon at any public event.

BTW - the G-11 is a great imaging mount too, but my 6" F/9 would be a bit much for reliable imaging on this mount.

(photo shows 6" F/9 on G-11 w extension. 80mm F/7 on alt-az is in front, kinda obscuring the mount. The crowd to the right is a line to look through the 6")


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urbanMark
sage


Reged: 07/08/06

Loc: San Jose, CA
Re: 6 inch refractor (visual) - which mount? new [Re: urbanMark]
      #5737082 - 03/16/13 08:05 PM Attachment (26 downloads)

Here is a better pic. Never ceases to amaze me how awestruck the general public is by this mount/scope combo. Can't tell you how often I've seen people walk right past AP's or big dobs to look through this rig. I can only guess that the tall pier and long-ish F/9 refractor are what draw people.

If outreach with a 6" class refractor is your goal, then the G-ll with pier extension is a great choice.


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Richard Low
professor emeritus
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Reged: 11/27/05

Loc: 1 deg N, GMT+8hrs
Re: 6 inch refractor (visual) - which mount? new [Re: urbanMark]
      #5737751 - 03/17/13 12:14 AM

I use my APM 6" f/8 triplet on EQ6 mount (no goto) for visual use and it is just alright. Yes there is some 2sec. vibration if tapped, but otherwise I have no problem viewing planets at 350x. I recently upgrade to Losmandy HD tripod and it is better. My DIY ota plus tube rings weight 12.2kg, while the APM 6" f/8 ED doublet, which I have tested, weighs about 10kg, so I would say the EQ6 mount is certainly useable. The G11 is definitely better, as I had mounted my APM 6" f/8 in tandem with AP 6" f/9 EDT and the G11 still performs well.

Incidentally, I also use the 6"/8 on Astroslew Inox, similar to DM4, with 12" pier on my Losmandy HD tripod, and it is a solid setup. I have use this setup for public outreach, and I have shown the public views of planets at 324x using Ethos SX 3.7mm.

Edited by Richard Low (03/17/13 12:23 AM)


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