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Equipment Discussions >> Binoculars

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Rich V.
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12" Binocular Telescope on Refractors
      #5638528 - 01/23/13 09:52 AM

Just a link to a post on Refractors showing pictures of a new 12" binocular telescope on an equatorial mount. It uses a "rotary clamp" similar to what I've seen on Matsumoto's site to keep the binos level for EQ viewing.

12" BT in Germany

Very cool!

Rich


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Andresin150
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Re: 12" Binocular Telescope on Refractors new [Re: Rich V.]
      #5638715 - 01/23/13 11:21 AM

Incredible!,
My 40x150's now look portable, aren't they?
amazing project!


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hallelujah
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Re: 12" Binocular Telescope on Refractors new [Re: Rich V.]
      #5638742 - 01/23/13 11:36 AM

http://www.astromart.com/classifieds/details.asp?classified_id=808439

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richsvt
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Re: 12" Binocular Telescope on Refractors new [Re: hallelujah]
      #5639267 - 01/23/13 05:17 PM

makes anything I have look like a toy.

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PhilCo126
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Re: 12" Binocular Telescope on Refractors new [Re: richsvt]
      #5643798 - 01/26/13 04:48 AM

Check the vendor topic:
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5636500


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: PhilCo126]
      #5643825 - 01/26/13 05:45 AM

why

edj


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5643829 - 01/26/13 05:50 AM

I can understand going up to 150mm (I have one),
but have never understood the logic, reason, usefulness
of the larger BT due to the cost, duplication of optics
Why not just get a larger scope with binoviewer?

Other than uniqueness,
doing it because you have the money and can,
what is the advantage of this binocular over a telescope?

edj


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Joad
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5644450 - 01/26/13 01:55 PM

I have the same questions, but I think I know the answer. There is a certain mystique to binoculars (as opposed to telescopes) that those of us on this forum have personally experienced. It is indeed far more rational to get a big truss dob and use a binoviewer. You can even move the big truss dob to a dark site, while this ton-and-a-half binocular must be permanently placed in a professional quality observatory. And there also seems to be a sort of unofficial law of diminishing returns when it comes to what binoculars can manage relative to magnification and precise collimation.

So I think I this is a harmless indulgence (at $500,000 it is a lot cheaper than I would have expected) on the part of someone with good taste and lots of money. There are a lot worse things to indulge oneself with, and this one will probably be a good investment on top of everything else.


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GlennLeDrew
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Re: 12" Binocular Telescope on Refractors new [Re: Joad]
      #5644484 - 01/26/13 02:18 PM

"...unofficial law of diminishing returns..." Unofficial indeed, for it does not apply.

If a gigantor of a binocular is not relevant, nor is any size bino. Whether big or small, one is using two eyes and hence enjoying the same gain in signal to noise. The improvement realized when going from, say, a 2" to a 4" bino is the same gain found when transitioning from a 6" to a 12" bino. It's all about ratios. And for given exit pupil diameter, the true bino always offers an image twice as bright as that of the BV-equipped mono job. The humongous bino is quite as relevant as any other size.


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Joad
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5644512 - 01/26/13 02:34 PM

Ah, but I'm not referring to the precisions of optical law; I'm referring to the fact that, say, a 100mm binocular telescope (like my BT) simply cannot manage the magnification of a good quality 100mm refractor, and is hugely sensitive to the slightest collimation offsets in a way that the telescope isn't.

I expect that this custom 12 inch binocular will be built with the intention of being so mechanically and optically perfect that it can perform equally with respect to a mid-sized telescope (I count 12" as mid-sized), but I wouldn't be surprised if the final result was not able to achieve such a level of perfection.

Some evidence for my expectations lies in the reviews I've seen of the giant reflector binoculars made by JMI. They are definitely not high magnification instruments, though their aperture is capable of very high magnification in a telescope.


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5644518 - 01/26/13 02:38 PM

Quote:

"...unofficial law of diminishing returns..." Unofficial indeed, for it does not apply.

If a gigantor of a binocular is not relevant, nor is any size bino. Whether big or small, one is using two eyes and hence enjoying the same gain in signal to noise. The improvement realized when going from, say, a 2" to a 4" bino is the same gain found when transitioning from a 6" to a 12" bino. It's all about ratios. And for given exit pupil diameter, the true bino always offers an image twice as bright as that of the BV-equipped mono job. The humongous bino is quite as relevant as any other size.




ok-I can see this

having the 12" binoculars are no more extreme to me
than me having 25x150s are to many others

thanks Glenn for the insight


edj


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faackanders2
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Re: 12" Binocular Telescope on Refractors new [Re: hallelujah]
      #5644526 - 01/26/13 02:40 PM

Quote:

http://www.astromart.com/classifieds/details.asp?classified_id=808439




WOW, It really is for sale. I thought is was made for someone or some observatory.


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faackanders2
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5644531 - 01/26/13 02:43 PM

Quote:

I can understand going up to 150mm (I have one),
but have never understood the logic, reason, usefulness
of the larger BT due to the cost, duplication of optics
Why not just get a larger scope with binoviewer?

Other than uniqueness,
doing it because you have the money and can,
what is the advantage of this binocular over a telescope?

edj




Wouldn't it have much wider TFOV for the aperture (than binoviewing with equivalent aperture)?


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faackanders2
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Re: 12" Binocular Telescope on Refractors new [Re: Joad]
      #5644544 - 01/26/13 02:49 PM

Quote:

Ah, but I'm not referring to the precisions of optical law; I'm referring to the fact that, say, a 100mm binocular telescope (like my BT) simply cannot manage the magnification of a good quality 100mm refractor, and is hugely sensitive to the slightest collimation offsets in a way that the telescope isn't.

I expect that this custom 12 inch binocular will be built with the intention of being so mechanically and optically perfect that it can perform equally with respect to a mid-sized telescope (I count 12" as mid-sized), but I wouldn't be surprised if the final result was not able to achieve such a level of perfection.

Some evidence for my expectations lies in the reviews I've seen of the giant reflector binoculars made by JMI. They are definitely not high magnification instruments, though their aperture is capable of very high magnification in a telescope.




Isn't the reason why people choose binos for the wide views (as mentioned binoviewers provide narrow views).


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EdZ
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Re: 12" Binocular Telescope on Refractors new [Re: faackanders2]
      #5644547 - 01/26/13 02:50 PM

depends on the f# of the scope being used to binoview and whether or not it has been designed (shortened as some are) to accomodate a binoviewer witthout the need for an OCS. If you were trying to use a scope/binoviewer to do this you would most certainly design in tose accomodations. In which case, fov then becomes a limitation of the eyepices that can be used. There are binoviewers that will allow use of a 45mm field stop. So, I would say this can easily be accomplished with a scope binoviewer combo. An 18" f/4 scope with a 45mm clear aperure binoviewer would easily accomodate the same field of view, at a fraction of the cost.

edz


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: faackanders2]
      #5644720 - 01/26/13 04:54 PM

Quote:

Quote:

http://www.astromart.com/classifieds/details.asp?classified_id=808439




WOW, It really is for sale. I thought is was made for someone or some observatory.




I am waiting for the "no reserve" auction

edj


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Mark9473
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Re: 12" Binocular Telescope on Refractors new [Re: faackanders2]
      #5644793 - 01/26/13 05:36 PM

Quote:

WOW, It really is for sale. I thought is was made for someone or some observatory.



The one that's finished now isn't for sale, it's going to China, but they're offering to build you another one by 2015.


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: Mark9473]
      #5645123 - 01/26/13 08:58 PM

it is really not that bad
only 35% down and
time payments over the next 2-3 years
let's see
-$175,000 down
-about $13,000 month x 24 months + any interest


edj


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GlennLeDrew
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5645311 - 01/27/13 12:05 AM

An arbitrarily large bino need not impose any particular difficulty whatsoever as regards similarity of image scale and collimation.

If we allow magnification to differ by 1-2%, as is the case for small binos, the allowable errors on radii of curvature simply scale in proportion, which poses no problem at all in fabrication.

Collimation is never problematic, no matter the magnification, when on-the-fly adjustment is afforded the user. Adherence to basic engineering practice for the avoidance of any significant differential flexure assures reliable performance.


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5645524 - 01/27/13 06:11 AM

Glenn,

that said,

what would one do with a 12" that could not be done with 4" or 6" binoculars?

when I have gotten larger binoculars,
there has always been a goal
-the Ms I couldnot find with smaller
-the AL H400s

I would guess better reach for comets,
galaxy groups, smaller open clusters
other objects better seen with binoculars than scopes?



edj


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GlennLeDrew
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5646001 - 01/27/13 12:47 PM

A 12" bino will see stars 4X, or 1.5 magnitudes fainter than could a 6". And at given exit pupil it will reveal twice the resolving power. Just as something like a big Dob is desirable for small, dim objects, so too is a binocular. A bino is not to be considered as merely a 'small' aperture, wide field instrument. When scaled up, benefits accrue just as they do for cyclopean optik tubes.

Mono scopes are, I contend, not natural. Most of us have two eyes, and so a binocular is the 'normal' instrument. It's not that a bino affords a *gain* in signal to noise of a factor of 1.414, but rather the mono scope is a *handicap* which reduces signal to noise to a factor if 0.707.


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Joad
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5646109 - 01/27/13 01:44 PM

I realize, Glenn, that my trying to discuss binoculars with you is like bringing a knife to a gun fight ( , but all I know is that I am not alone in my once hoping that a 100mm interchangeable eyepiece BT could be an all-purpose astronomy instrument. It isn't. Not even close. In the very best of circumstances I can crank it up to about 85X, but the image is dim and the collimation tolerances dicey (even with my in-the-field adjustments, which my variety of Oberwerk allows for). Now, since the summation effect of two 100mm objectives is somewhere around 120mm (or, roughly, five inches), a 100mm binocular is roughly the aperture equivalent of a five inch telescope. But a good five inch refractor can easily go to over 200X. The highest any of us here on CN has gone is 150X, and that is with a special Miyauchi, and the person who owns that binocular does not often view at 150X. EdZ, with his 100mm Oberwerk, tends to stick to magnifications under 60X.

I will grant that if everything is absolutely perfect, mechanically and optically, with a binocular, in theory it should perform right up there with a telescope, but I've never seen that actually accomplished. Maybe the half million dollar monster will be the exception. I hope we find out some day.


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Tamiji Homma
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Re: 12" Binocular Telescope on Refractors new [Re: Rich V.]
      #5646138 - 01/27/13 02:09 PM

I am wondering if the giant binoscope goes to this location?

If it were true, it must be one of those life altering experiences in various ways.

Savio Fong's post

5100m observatory

Tammy


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Andresin150
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Re: 12" Binocular Telescope on Refractors new [Re: Joad]
      #5646177 - 01/27/13 02:35 PM

I think what Joad wants is not only possible but already exists.. The problem: cost. But for example a Bt out of a couple 102 Taks (or bigger) and a Matsumoto mirror setup will probably take you there.
But I'm not ready to go there, for me, just like the 12" Bt, this is telescope (high mag) realm. Binoculars, regardles of size, are different in their relatively small size for the aperture, big TFov for the magnification, correct image suitable for terrestrial use or simply to make them more user friendly..., the use of two eyes (and its obvious advantages) is a feature, but not exclusive of binoculars, same as portability...
So, if I wanted high magnification images, for example for planetary observation, those 12" could be a great instrument and should be considered by anyone that could afford them, but if those where mine, those would get to be used like a telescope, just like one that happens to be able to be used with both eyes...., but never like a binocular


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Mark9473
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Re: 12" Binocular Telescope on Refractors new [Re: Andresin150]
      #5646258 - 01/27/13 03:22 PM

I think you're right Tammy!

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Jawaid I. Abbasi
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5646416 - 01/27/13 04:44 PM

http://www.stathis-firstlight.de/atm/joerg_28bino.htm
Check this out


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GlennLeDrew
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Re: 12" Binocular Telescope on Refractors new [Re: Jawaid I. Abbasi]
      #5646613 - 01/27/13 06:24 PM

Commercial binos, with all the inexpensive optical elements within, can hardly be expected to perform in what for the aperture is the higher magnification regime. An instrument which will 'do it all' can be easily had, and for much less than a half mil. A couple of 5" APOs and the Matsumoto EMS system is one ready solution.

The 5" f/5 achro bino I built for a friend years ago--principally for DSO observation--worked pretty well up to ~130X (1mm exit pupil). The limiter was the chromatic aberration inherent in such an objective, followed by the 1/3 wave spherical aberration also inherent. The three mirrors in each side, being in the 1/10 wave regime, did no harm. Better objectives would have made for a decent enough planetary instrument.

And collimation was never a concern, for a quick twist of a little knob restored it in seconds.


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GamesForOne
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5646943 - 01/27/13 09:02 PM

Well, with the instrument in question one should be able to put a binoviewer on one tube of the instrument and push to high power. I imagine the objectives are APO-quality and the rear can be fitted with a standard diagonal.

So the instrument likely provides both binocular vision and high magnification capabilities.

There is no reason a 100mm binocular telescope could not be operated the same way if it was designed appropriately. The limitation is cost. There is no reason the two have to be exclusive.

---
Michael Mc


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edwincjones
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Re: 12" Binocular Telescope on Refractors new [Re: GamesForOne]
      #5647548 - 01/28/13 08:07 AM

may be a good time to reintroduce the JMI Reverse BTs.
they go up to 16" but have not been very popular here

I have never used one,
am concerned that they are hard to adjust/use
buy once considered one (briefly ) of the larger ones instead of a big dob (16" bt vs 24" dob) due to avoiding a ladder (that I would most likely fall )

not the same, but from a practical money issue, much cheaper



edj


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Mr. Bill
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Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5648354 - 01/28/13 02:30 PM

Interesting discussion...

My own thought is that a big dob + binoviewer is the best practical solution. Big aperture binos in the 12 inch and up range are unwieldy and require a permanent location (or lots of time to assemble/disassemble.)

I have looked through a 20 incher at GSSP and while enjoying the views I was just as impressed with views through a big dob+BVs.



Edited by Mr. Bill (01/28/13 03:35 PM)


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faackanders2
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Re: 12" Binocular Telescope on Refractors new [Re: Mr. Bill]
      #5649257 - 01/28/13 09:01 PM

Large Dob and binoviewers offers option to use single eyepiece for fainter and wider objects.

Binocular offers advantage of much wider views, but are limited to lower power for reasons I don't understans (prisms?, brain merging images, etc). JMI reverse binos I would think would not be limited to higher powers.


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CuriousOne
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Re: 12" Binocular Telescope on Refractors new [Re: faackanders2]
      #5649775 - 01/29/13 07:08 AM

The military has another type of "binoculars", I don't know how exactly they are named, but their input lens have distance about 2 meters between each other. While the specimen I've tested had only maybe 8x magnification, it was providing amazing 3d effect, when even distant mountains weren't flat any more, and you can clearly see which one is closer and which one is on the back.

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planetmalc
sage


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Re: 12" Binocular Telescope on Refractors new [Re: CuriousOne]
      #5650147 - 01/29/13 11:55 AM

Having lugged 5" binoculars out to the back yard for donkey's years, I'm firmly of the opinion that a pair of 6", ideally built with light weight in mind, is the limiting aperture UNLESS you plan to leave the thing outside. If you want one-man portability AND more light grasp then it has to be commercial or home-built JMI-style reflectors, or a 'scope + binoviewer (a Dob if you must have low powers or an SCT if you like high mag). You couldn't GIVE me that 12", unless it came already installed in a decent observatory, in a property with great skies. Anything less would be a waste.

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KennyJ
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Re: 12" Binocular Telescope on Refractors new [Re: CuriousOne]
      #5650154 - 01/29/13 12:00 PM

Fackanders,

The reason conventional binoculars tend to be relatively restricted magnification-wise as compared with Binoviewing is nothing to do with prisms or the human eyes.

It is simply because TRUE COLLIMATION is absolutely necessary, and can be tricky to achieve and maintain at magnifications in excess of around 50x.

Kenny


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ThomasM
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Reged: 04/19/09

Re: 12" Binocular Telescope on Refractors new [Re: planetmalc]
      #5660551 - 02/03/13 06:38 PM

Quote:

Having lugged 5" binoculars out to the back yard for donkey's years, I'm firmly of the opinion that a pair of 6", ideally built with light weight in mind, is the limiting aperture UNLESS you plan to leave the thing outside. If you want one-man portability AND more light grasp then it has to be commercial or home-built JMI-style reflectors, or a 'scope + binoviewer (a Dob if you must have low powers or an SCT if you like high mag). You couldn't GIVE me that 12", unless it came already installed in a decent observatory, in a property with great skies. Anything less would be a waste.





I agree, if you don't live under a dark sky a 6" instrument is an excellent choice. I built such an instrument

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3720212/page...

with 160 mm f/6.5 oilpaced apo lenses, total weight 11.8 kg. Such an instrument can easily be transported to a dark side and hooked up to a mount. The big advantage compared to a bigger refractor with binoviewer, the large field, with 17 mm Ethos I get 1.6 degree TFOV at 65x maginification.

Thomas


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GlennLeDrew
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Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5661211 - 02/04/13 07:11 AM

Kenny,
Dangerous to make such a blanket statement that about 50x is the limit for binoculars due to collomation constraints! The *first* bino I ever made was a 5 incher. The collimation adjustment built in posed no problem whatsoever at 130X, and could have proved eminently practicable at twice that power, if the optics allowed.

The all too common misconception that magnification somehow invalidates good engineering drives me more than a little barmy.


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faackanders2
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Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5661525 - 02/04/13 11:01 AM

Quote:

Quote:

Having lugged 5" binoculars out to the back yard for donkey's years, I'm firmly of the opinion that a pair of 6", ideally built with light weight in mind, is the limiting aperture UNLESS you plan to leave the thing outside. If you want one-man portability AND more light grasp then it has to be commercial or home-built JMI-style reflectors, or a 'scope + binoviewer (a Dob if you must have low powers or an SCT if you like high mag). You couldn't GIVE me that 12", unless it came already installed in a decent observatory, in a property with great skies. Anything less would be a waste.





I agree, if you don't live under a dark sky a 6" instrument is an excellent choice. I built such an instrument

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3720212/page...

with 160 mm f/6.5 oilpaced apo lenses, total weight 11.8 kg. Such an instrument can easily be transported to a dark side and hooked up to a mount. The big advantage compared to a bigger refractor with binoviewer, the large field, with 17 mm Ethos I get 1.6 degree TFOV at 65x maginification.

Thomas




Thomas how much did your 6" bino telescopes cost to make?

Ken


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Rich V.
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Re: 12" Binocular Telescope on Refractors new [Re: GlennLeDrew]
      #5661539 - 02/04/13 11:08 AM

I agree; with a properly designed and built bino, retaining collimation even at relatively high magnification shouldn't be a problem.

I've been transporting my Miyauchis on dirt roads in the back of a truck for years now and collimation has stayed unchanged even at 150x which is the shortest eyepiece set I have to view with. The robust mechanical design of the main prism and turret assys seems pretty bulletproof to me.

Good mechanical design and execution is necessary, though. Many commercially produced binos made to a price point may not make the cut!

Rich


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KennyJ
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Re: 12" Binocular Telescope on Refractors new [Re: Rich V.]
      #5661663 - 02/04/13 12:27 PM

Glen and Rich,

I never said collimation was IMPOSSIBLE with binoculars at magnifications above 50x, I just stated that it CAN be TRICKY.

There's certainly nothing "dangerous" about that statement whatsoever.

I'm surprised at you two not paying more attention to detail ! :-)

Kenny


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Rich V.
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Re: 12" Binocular Telescope on Refractors new [Re: KennyJ]
      #5661738 - 02/04/13 01:03 PM

Quote:

I'm surprised at you two not paying more attention to detail ! :-)




Guilty as charged, Kenny! I think term "tricky" can certainly be an appropriate term, particularly in some designs. Having easy to access external adjustments or robust internal ones is essential. If collimation demands wiggling eyepieces or shimming prism turret covers to overcome design or build deficiencies, it's too tricky for me!

Rich


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ThomasM
sage


Reged: 04/19/09

Re: 12" Binocular Telescope on Refractors new [Re: faackanders2]
      #5662067 - 02/04/13 04:17 PM

Quote:

Quote:




I agree, if you don't live under a dark sky a 6" instrument is an excellent choice. I built such an instrument

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3720212/page...

with 160 mm f/6.5 oilpaced apo lenses, total weight 11.8 kg. Such an instrument can easily be transported to a dark side and hooked up to a mount. The big advantage compared to a bigger refractor with binoviewer, the large field, with 17 mm Ethos I get 1.6 degree TFOV at 65x maginification.

Thomas




Thomas how much did your 6" bino telescopes cost to make?

Ken




Ken,

I can not give an exact number, it took me almost three years to construct the instrument and I did not count all expenses. All in all, I guess the total costs were about twice as much as that of a high quality comercial 150-160 mm apo refractor.

Thomas


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ThomasM
sage


Reged: 04/19/09

Re: 12" Binocular Telescope on Refractors new [Re: KennyJ]
      #5662076 - 02/04/13 04:27 PM

Quote:

Glen and Rich,

I never said collimation was IMPOSSIBLE with binoculars at magnifications above 50x, I just stated that it CAN be TRICKY.

There's certainly nothing "dangerous" about that statement whatsoever.

I'm surprised at you two not paying more attention to detail ! :-)

Kenny




just to add one point, the impressive 12" instrument, but also my 160 mm binocular telescope have two knobs (for left/right, up/down each) which allow perfectly overlaying the two images . This mandatory for high magnifiction and very comfortable to use.

Thomas


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joe nastasi
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Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5662102 - 02/04/13 04:45 PM

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.

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ThomasM
sage


Reged: 04/19/09

Re: 12" Binocular Telescope on Refractors new [Re: joe nastasi]
      #5667529 - 02/07/13 05:25 PM

Quote:

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.



Assuming that this is correct, why does somebody who can affort it waists so much money?



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GamesForOne
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Reged: 09/29/09

Loc: Knoxville, TN
Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5667566 - 02/07/13 05:54 PM

Quote:

Quote:

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.



Assuming that this is correct, why does somebody who can affort it waists so much money?






That is quite an assumption. Such a question risks opening the can of worms as to which telescope design puts up a better image. Frankly, my 105mm TMB-designed APO lens with AP diagonal shows an absolutely textbook star image. Observing double stars with it is a joy with good seeing, with or without a binoviewer.

I've yet to observe through a newt that shows such a sharp and perfectly collimated image with such ease and consistency, especially with increasing magnification, and I've used and owned Zambuto mirrors.

Not to mention the fact that you have no central obstruction from a secondary or diffraction spikes...

If I had the money I sure would enjoy that view!

---
Michael Mc


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Mr. Bill
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Loc: Northeastern Cal
Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5667592 - 02/07/13 06:10 PM

Quote:

Quote:

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.



Assuming that this is correct, why does somebody who can affort it waists so much money?






Because they can...


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Mark9473
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Reged: 07/21/05

Loc: 51°N 4°E
Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5668795 - 02/08/13 11:36 AM

Quote:

Quote:

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.



Assuming that this is correct, why does somebody who can affort it waists so much money?




Without going into the specifics of both instruments or their cost, you need to realize that for a given size exit pupil, the image with a binoviewer is only going to be half as bright as in a binoscope.

So at least on that parameter, take "outperform" with a grain of salt. However there are obviously very many other parameters that come into play in what somebody would call "performance".


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edwincjones
Close Enough
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Reged: 04/10/04

Re: 12" Binocular Telescope on Refractors new [Re: ThomasM]
      #5670313 - 02/09/13 08:54 AM

Quote:

Quote:

Nice project but a near perfect 16"-18" equatorial Newtonian with a high quality binoviewer will outperform it for $490K less.



Assuming that this is correct, why does somebody who can affort it waists so much money?






take any binocular (or optics) ever mentioned on CNs,
someone would think that it was a waste of money,
either too expensive or too cheap for their tastes

we are a diverse group
edj


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ErixAdministrator
Toad Lily
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Reged: 12/25/04

Loc: Texas, USA
Re: 12" Binocular Telescope on Refractors new [Re: edwincjones]
      #5671227 - 02/09/13 07:06 PM

Quote:



take any binocular (or optics) ever mentioned on CNs,
someone would think that it was a waste of money,
either too expensive or too cheap for their tastes

we are a diverse group
edj




Isn't that the truth, and thankfully so. What works best for one person doesn't necessarily fit the bill for the next. Thanks for that reminder!


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