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Biggest eyepiece ocular lens - is there bigger than swarovski SLC 8x56 ? (1 Viewer)

kimmik

Well-known member
United Kingdom
So looking for something a little different, I’m trying out the 8x56 SLC for two weeks.

The thing that struck me the most is the size and flatness of the ocular lens, like a big window vs small window feeling. This is in addition to the huge exit pupil.

Measurement of the ocular lens diameter:

SLC 8x56 - 29mm
NL - 25mm
EL - 24mm

Has anyone seen binoculars with larger ocular lens than this?

I know the Nikon WX is up there, but not sure what the lens measurement is.
 

Tringa45

Well-known member
Europe
I suspect that the 8x56 SLC would have to be the record holder amongst hand-held binoculars.
There is a relationship between eye lens diameter, eye relief and AFoV and I tried to explore this a few years ago as my alter ego, John Russell, The Relationship of Eye Relief to Eye Lens Diameter and FOV, though I now think some of that is rather flawed as it fails to take account of other factors such as vignetting.

The 23 mm eye relief of the 8x56 could almost be described as excessive. As a glasses wearer I have to extend the eyecups by 6 mm (2 mm beyond the first stop) for a comfortable view.

John
 

William Lewis

Wishing birdwatching paid the bills.
United Kingdom
You may struggle to give them back as long as you don't struggle to carry them.

I don't like commenting on best or worst but having said that I think the view through the 8x56's is the best view you can buy in a binocular without resorting to some serious exotica - once you've got them set up right! My mate had a go with mine at the weekend and really didn't want to give them back "better than real life" were his exact words...
 

PeterPS

MEMBER
So looking for something a little different, I’m trying out the 8x56 SLC for two weeks.

The thing that struck me the most is the size and flatness of the ocular lens, like a big window vs small window feeling. This is in addition to the huge exit pupil.

Measurement of the ocular lens diameter:

SLC 8x56 - 29mm
NL - 25mm
EL - 24mm

Has anyone seen binoculars with larger ocular lens than this?

I know the Nikon WX is up there, but not sure what the lens measurement is.
Huet Mirapan 8x30 (FoV=11.4*) are likely the binos with the biggest eye lenses I ever owned---see the attached photo.
One of the two examples that I owned was internally cleaned by Cory Suddarth and he told me that he's never seen a bino with bigger ocular lenses. Unfortunately I sold both examples so I cannot measure the diam of the lenses.
 

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kimmik

Well-known member
United Kingdom
Huet Mirapan 8x30 (FoV=11.4*) are likely the binos with the biggest eye lenses I ever owned---see the attached photo.
One of the two examples that I owned was internally cleaned by Cory Suddarth and he told me that he's never seen a bino with bigger ocular lenses. Unfortunately I sold both examples so I cannot measure the diam of the lenses.

Impressive 90deg afov!

I have an 8x30 with 10deg fov, lens definitely smaller than that. Sadly the image is a little dull compared to modern offerings, and the eye relief of course…
 

kimmik

Well-known member
United Kingdom
There are some cool examples of astronomical (pun intended) eyepieces - second page, one guy made an eyepiece with 92mm eye lens…

Thats bigger than many telescope objectives!

He says its not eye-relief anymore, but face-relief. 😱

 

William Lewis

Wishing birdwatching paid the bills.
United Kingdom
Just toying with this idea, Kimmik do you happen to have any doublers or tripplers kicking about?

Just wondered given the nature of the SLC 8x56 if you were planning on sticking one on to see how it works as a low mag scope other than just for resolution testing purposes? I know, loads more glass elements including a set of sp prisms but if it's going to work ok on any bin it's got to be the SLC right?
 

kimmik

Well-known member
United Kingdom
Just toying with this idea, Kimmik do you happen to have any doublers or tripplers kicking about?

Just wondered given the nature of the SLC 8x56 if you were planning on sticking one on to see how it works as a low mag scope other than just for resolution testing purposes? I know, loads more glass elements including a set of sp prisms but if it's going to work ok on any bin it's got to be the SLC right?

Very interesting idea William. I’ll try in a few days when i get back from a trip. At very least I could piggy back the EL 8x32, making 64x56 binoculars lol. Will be 80% transmission 0.8mm pupils hmmmm

Edit: oh the cl 7x21 might be even better suited to this, 1mm pupil!
 

tenex

reality-based
Kimmik, there's a nice 8x56 SLC currently in the classifieds here.

The 23 mm eye relief of the 8x56 could almost be described as excessive.
I doubt I'd be able to use it comfortably; I already have eyecups from the 8x on my 10x56! Is 23mm just an accidental result of the focal length needed, rather than an intended feature?

Swarovski makes / made a magnification doubler for the SLC x 56.
That's only for the pre-HD models, it doesn't fit onto the new ones. One could use a monocular instead like Zeiss 3x12.
 

kimmik

Well-known member
United Kingdom
Ah yes I am currently in the UK but otherwise would have considered the one in classified. Thank you for the tip tenex :)
 

Thotmosis

Well-known member
Netherlands
That's only for the pre-HD models, it doesn't fit onto the new ones. One could use a monocular instead like Zeiss 3x12.
Good to know Tenex. Does Meopta still has the setup with a doubler for x56 like Swarovski did? If so does this setup can be used as an “emergency” spotting scope? Would tilt me direction Meopta if the IPD would work for me.

EDIT: In this video Meopta x56 is used with a doubler. Might be useful as an emergency scope.

 
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kimmik

Well-known member
United Kingdom
The SARD USN Mk-43 6x42 with 11.8° FOV sports 27mm oculars. Looking through them is like going on a spacewalk. :)
Jack

Epic! That is begging to be remade… not sure if physically possible in roof format, NL 6x42 12degree, get rid of the field flatteners and call it special edition… could sell for even higher 🤤
 

Tringa45

Well-known member
Europe
I doubt I'd be able to use it comfortably; I already have eyecups from the 8x on my 10x56! Is 23mm just an accidental result of the focal length needed, rather than an intended feature?

The eyecups of the 8x56 SLC extend up to 16 mm, so the large ER should not pose a problem for users not wearing glasses. The next highest ER I am aware of is the7x42 Meostar with 22mm and its eyecups extend 14 mm.

Eyepiece design is complex and probably expensive. I speculated in another thread that the eyepieces for the 56 mm SLCs were scaled, which would at least enable Swarovski to use the same optical glasses for the individual elements. Hence it would have been logical to optimize the design for the 10x56 with an ideal ER of 19,5 mm at something around 20 mm focal length. Scaled up for the 8x56 resulted in somewhat excessive 23 mm ER, and scaled down in inadequate 16 mm for the 15x56, at least for glasses wearers.

John
 

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