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Intro to Binocular Viewing


Eric Weiner
 

I’m examining the pros, cons, details, and pitfalls for entering into the world of binocular viewing for use with my Tak 130mm f7.7 (I’m not one of the fortunate ones to own an AP130) and possible a M-300CRS. I thought this would be an appropriate place to ask for information since many of you undoubtedly are well versed in the use of binos, and Roland has done what looks to be quite a bit of design work for accessories. 


I believe you get what you pay for so the the Baader MkV are what I’m considering. Any information would be welcome since I’m a complete newbie at this type of viewing method.


Besides the obvious con of cost for the binos and eps, what are some other cons? Do those with experience consider the pros to outweigh the cons? What not-so-obvious info should I consider before buying a set? How does one select the appropriate accessories such as Barlows and compensators?

Thanks in advance,
Eric 


Vahe
 

I am strictly visual, planets, the Moon and double stars are my primary interest these days. For these subjects binoviewers are the ideal tool.
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I bought my first binoviewer from Astro-Physics back in 1994, it was Zeiss viewer that I still own and is my favorite. A year later Zeiss stopped making astro toys for the amateur market and Baader took over offering these same viewers with Zeiss glass.
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Pros and Cons: First the Cons, these are expensive accessories when you consider the Baader MarkV and that is just the beginning, you will need two identical eyepieces which adds up quickly.

Pros; Here is the way that I see it, we are all born with two eyes, it is just more comfortable to use both eyes, you will get 3D effect when viewing Solar System objects with binoviewer, in my case I suffer from excessive floaters that makes monoviewing hopelessly frustrating, with binos these darn floaters do not inflict much damage to what I can see in the eyepiece.
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I still remember my first view of Moon in my new Zeiss viewer with a pair of 22-mm Panoptics and Roland's newly designed 2X Barlow at 158x, it was like floating in space over the badlands of the Moon.
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After that experience I never went back to monoviewing again, I always use my Zeiss viewer or my second Baader viewer. 
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The increased amount of detail that can be seen on planets using a binoviewer is another reason for having one.

And finally, if you want a binoviewer definitely go for a quality product, and if you can afford it stay away from less expensive imported units. 
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They will tell you that a binoviewer with a pair of cheap eyepieces will outperform the views obtained in mono mode using a single high end eyepiece, this I agree, but wait  until you see what happens when you use a pair of high end eyepieces in a quality viewer!!!!!!!  
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There are folks who seldom use binoviewers, you need to hear from them as well before making a decision, they will bring up some of the negatives in connection with viewer including inability to merge images, this has not been a problem for me even with high power eyepieces, but I hope some of these folks give you their opinions on the subject.
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Vahe 


Ross Elkins
 

Hi, a worthy upgrade!
there are some of us who think the binotron 27 from Denkmeier is the best thing on earth and there’s others that own other fine brands they will mention. Check them all, then buy a denkmeier binotron! With its many accessories for multiple magnifications, filters and the largest prisms at last count, with excellent controls and adjustments, its nicer than the other 5 brands i’ve owned!
One down side is $$! Two of each nice and costly EP! I have 5 pairs and am looking for my sixth, a pair of televue 3-6 zooms! This EP has gotten real pricy in the last 10 years. One bad thing is you get a real narrow fov! You need good goto’s but the folks on this site don’t generally suffer from that. Just Saying! Good comes from the light beam that splits in half to each ocular, so no filters to protect your eyes when observing bright planetary’s like the Moon!
The moon becomes a real show for me on my 155 and surprisingly entertaining on the new Stowaway... And isn’t that what we all want, to be entertained🤠
Have fun with whatever you buy and be entertained!
Rossmon


Holger
 

I have not used a binoviewer yet, but once learned that it should preferably be used in combination with a barlow lens to avoid aberrations caused by the prisms. Is this an issue? If so, the choice of eyepiece focal lengths has to be made accordingly.

Cheers,
Holger 


Vahe
 

Zeiss/Baader type binoviewers come with Glasspath corrector (1.25x) that takes care of prism induced aberrations, GPC's are available in 1.25x, 1.7x and 2.6x factors.
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Vahe


Holger
 

Thanks for that clarification!

Holger


Eric Weiner
 

Vahe,

How does one choose the correct glasspath corrector?

Thank you,
Eric


Vahe
 

It all depends on the type of scope you are using.
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If you are using a short and fast refractor, one primarily optimized for imaging, and would like to get a decent magnification on planets without resorting to very short and uncomfortable eyepieces then you should consider a GPC with either 1.7x or 2.6x factor. If you have a larger instrument then the 1.25x is what you will need.

GPC’s are inexpensive and it is a good idea to have at least two of them on hand.
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Vahe


George
 

Vahe,

 

Another good idea is to use our Barlow (BARADV), the optic section, screwed onto the front of the bino nosepiece for more magnification.    This will narrow and lengthen the light cone for better performance.    Most magnification should be done in front of the bino.

 

Regards,

 

George

 

George Whitney

Astro-Physics, Inc.

Phone:  815-222-6538 (direct line)

Phone:  815-282-1513 (office)

Email:  george@...

 

From: main@ap-ug.groups.io <main@ap-ug.groups.io> On Behalf Of Vahe
Sent: Tuesday, April 6, 2021 10:56 AM
To: main@ap-ug.groups.io
Subject: Re: [ap-ug] Intro to Binocular Viewing

 

It all depends on the type of scope you are using.
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If you are using a short and fast refractor, one primarily optimized for imaging, and would like to get a decent magnification on planets without resorting to very short and uncomfortable eyepieces then you should consider a GPC with either 1.7x or 2.6x factor. If you have a larger instrument then the 1.25x is what you will need.

GPC’s are inexpensive and it is a good idea to have at least two of them on hand.
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Vahe


Eric Weiner
 

Thanks Vahe.  It sounds like having a full complement is the best way to go. What I was hoping to find out was the math that goes into why which GCP is better for any particular scope. I have found a number of folks discussing which gpc is good for which type of scope, but I’m having a difficult time finding any literature online which discusses the theory. 


George, thanks. Yes, I understand why having the Barlow up front is important. 


Vahe
 

It is not very simple once you get into this, GPC’s in a way are a form of a Barlow, they magnify the image while correcting prism aberrations at the same time.
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When I bought my Zeiss viewer back in 1994 I also bought a 2x Barlow (2”) that Roland had deigned and produced specifically for this particular viewer, it fits in between the prism diagonal and the viewer.
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I would also suggest that you look into Cloudy Night Forums under “Equipment  Discussions” where you will find “Binoviewers” Forum. Tons of discussions related to binoviewrs. Of course like any discussion forums open to general public you need to be careful and be able to sort out facts from “over the top” opinions. 
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Vahe


Alan Friedman
 

Sometimes mechanical requirements come into play - such as being able to reach focus on a particular scope. I find using both eyes to be very helpful in solar observing through my Ha filter. With the blocking filter added to the optical path behind my f5 Stowaway, I need the highest magnification GPC to reach focus. With two Televue 32mm Plossl eyepieces, the full disk of the sun will fill the field of view and provide very nice contrast.

Clear skies,
Alan




On Apr 6, 2021, at 11:26 AM, Eric Weiner <weinere@...> wrote:

Vahe,

How does one choose the correct glasspath corrector?

Thank you,
Eric


Eric Weiner
 

Of course like any discussion forums open to general public you need to be careful and be able to sort out facts from “over the top” opinions. 
Very true. I didn't think to look on CN.  As you stated though, it can be a chore sorting through too many people's ideas.  I find it always easier to stick to the opinion of a few subject matter experts, or at least those who have years of practical experience.  

Eric


Gary C Fairview TX
 
Edited

Eric,

CN has a forum dedicated to binoviewing and you will find a plethora of information on the subject there. One fellow who comes to mind goes by the handle “Eddgie“ is very knowledgeable about the use of binoviewers with many different scope types and accessories for solar and night observing. Another contributor is a fellow from Croatia who tunes and builds a number of custom binoviewers from Zeiss microscope heads. His handle is denis00007dl.

https://www.cloudynights.com/forum/65-binoviewers/