Leica 8x56 BRF (1 Viewer)

[Omid]

I always wished Leica would bring out a cool 5x56 binocular along the same lines as the good old Zeiss 8x56 Night Owls. Well, now they have one out but its a BRF model with an integrated laser range finder! I am not totally dissapointd so I have started resaerching these.

Has anyone looked through or examined these binoculars in person? Specifically, I would like to know how the feild of view "feels". At 6.8 degrees (54 degrees apperent), they are not considered wide-angle but I expect that there should be no "tunnle-vision feel" when you look through them (?)

A side point: I notice that binoculars with larger exit pupoil generally provide a nice feild of view even when their actual feild of view is not very generous. I attribute this to the fact that you can use a wider inter-barrel distance while still keeping your eye pupils inside the binoculars' exit-pupil. Wuould you guys agree?

 

[hinnark]

. 1. At 6.8 degrees (54 degrees apperent), they are not considered wide-angle but I expect that there should be no "tunnle-vision feel" when you look through them (?)

2old2Care,

I have used them and I would say that FOV feels exactly how you have described it. No widefield feel but definitely no tunnle-vision. The 8x56 Geovid has very long eye relief (ap. 19 mm real) and the provided contrast is perhaps the strongest I´ve seen so far in any piece of optics. It is one of the most lightweight and compact 8x56 bins I know. I found also the rangefinder function quite useful.

I cannot confirm that a wider inter-barrel distance has an effect on AFOV.

Steve

 

[Omid]

Thank you very much for your comment Steve.

I haven't seen any sample of the 8x56 BRF in retail shops here in Florida yet. I am comming to Berlin for a buisness trip next week. I'll try to drop by Frakonia or other Leica dealers in the Berlin area hoping to get the chance to examine one in person.

Do you have any recommendations for a good binocular/optics store in the Berlin area?

Thanks
-Omid

 

[hinnark]

Omid,

This very nice shop has all the Leica stuff but no other brands:
http://www.leica-camera-berlin.com/index.php?id=37&L=1

This is a dealer for hunters with several brands:
www.triebel.de

There are some good books available about the birds of Berlin. Unfortunately "Important Bird Areas (IBA) in Brandenburg und Berlin" is out of stock now. Maybe this book is of some interest:

Milne : World Cities : "The essential guide to finding birds in the major cities of the world",
where Berlin is included.

I wish you a nice trip and a good time in Germany.

Steve

 

[Omid]

Dear Steve,

Thank you very much for the link to the Leica shop. I will definitly check it out.

I have to mention that I am not much of a bird watcher. My interest in binoculars is for nature observation and hunting. I also have a vested interest in optics in gerneral.

Oh, and I think it's time to update my profile. I no longer live in Toronto (I live in Palm Beach, Florida now) and I am not as old as my my login name says (see http://www.omidjahromi.com/)


-Omid

 

[elkcub]

... A side point: I notice that binoculars with larger exit pupoil generally provide a nice feild of view even when their actual feild of view is not very generous. I attribute this to the fact that you can use a wider inter-barrel distance while still keeping your eye pupils inside the binoculars' exit-pupil. Wuould you guys agree?

Omid,

This would be hard to agree with on its face. The angular FOV is fixed by design (usually the field stop in front of the eyepiece), and the apparent field is M times that, where M is magnification. If the eye looks through the nasal side of a large exit pupil, this doesn't increase the real angle. Forcing a wider inter-barel distance (i.e., distance between the centers of the two objectives) in this way would increase the disparity between the two retinal images and provide slightly more stereopsis or spatial depth. However, in this instance cross-axis viewing would require divergence rather than convergence of the eyeballs, which is distinctly not how they like to operate.

More than likely, your larger exit pupil binoculars also have large objectives with centers that actually are several mm farther apart than your inter-pupil distance (IPD). As stated above, and recently on another thread, this would give the illusion of more spatial depth, which may give you the impression of more FOV.

That's my impression. I'd be happy to discuss it further if you wish. Congratulations on your new book.

Blue skies,
Ed

 

[John Russell]

Ed,

Could there be a misunderstanding here? Perhaps Omid meant the adjusted ipd of the binoculars when referring to "inter-barrel distance."

With large exit pupils of 6mm or 7mm one is able to view the edges of the fov in good lighting by rotating one's eyes. However, with small exit pupils this will lead to blackouts unless the the oculars are shifted left/right or up/down with respect to one's face. Of course, peripheral vision allows one to perceive the edges of the fov but a detailed assessment requires some realignment. This realignment is a lot easier if the binoculars (or scope) are fixed, i.e. mounted on a tripod.

I think this explains the viewing comfort, even in good lighting, of bins with large exit pupils and the pointlesness of a large afov on compact bins with small exit pupils.

Regards,

John

 

[elkcub]

Ed,

Could there be a misunderstanding here? Perhaps Omid meant the adjusted ipd of the binoculars when referring to "inter-barrel distance."

With large exit pupils of 6mm or 7mm one is able to view the edges of the fov in good lighting by rotating one's eyes. However, with small exit pupils this will lead to blackouts unless the the oculars are shifted left/right or up/down with respect to one's face. Of course, peripheral vision allows one to perceive the edges of the fov but a detailed assessment requires some realignment. This realignment is a lot easier if the binoculars (or scope) are fixed, i.e. mounted on a tripod.

I think this explains the viewing comfort, even in good lighting, of bins with large exit pupils and the pointlesness of a large afov on compact bins with small exit pupils.

Regards,

John

John,

You could be right that Omid meant something other than what I interpreted. I tried to pick a question that could be answered fairly easily.

In truth, I avoid the edge viewing conundrum, which has been discussed on BF and CN to a fare-thee-well. I plead nolo contendere, admit to nothing, and trust to the mercy of the system.

Blue skies,
Ed

 

[Omid]

John,

You could be right that Omid meant something other than what I interpreted. I tried to pick a question that could be answered fairly easily.

Blue skies,
Ed

Yes, what I meant by increasing the ipd was simply adjusting the ipd by hand so that the barrels are as far away from each other as possible. This way the FOV is no longer a perfect circle, it will look like two overlapping circles (like they show in the movies when the actor is seeing something through binoculars). It seems to me that the amount that the ipd can be increased without causing viewing discomfort (about 90% overlap), is larger for binoculrs with larger exit pupil. But this, as Ed said, requires the eyes to align along diverging directions so maybe in the long term is not comfortable?

anyhow, I examined the Leica 8x56 BRF in the Berlin Leica store yesterday. Holy Sh@#!!! Fantastic view! Very rich in contrast and comfortable too. This is bad news... Very bad news for my depleted bank account indeed...

 

[elkcub]

Omid,

I think most folks would agree that forcing the FOV that way is not a good idea because of cross-axis aberrations and eye strain. Actually, though, you have a wider natural FOV using two eyes than one, since the two views only overlap in the center; the extremes being monocular viewing. In that case, however, there is no cross-axis issue.

My largest objectives are 44mm, which show up in the standard 8.5x44 804 HR/5 Audubons. These went out of production about 2000 but are worth having with their remarkable clarity, sharpness, and 70 deg. FOV. No forcing required here. The 804ED, in my opinion, can't be bested for center color resolution. And they only weigh 29.5 oz, (which some say is too heavy to carry).

Blue skies,
Ed

 

[Omid]

I am back in Florida after a nice trip to Berlin, Vienna and Bratislava! My day-night timing is still messed up due to jet-lag but I managed to do some updates to my profile. It now correctly shows that I am in Palm Beach rather than Toronto, Canada! I also asked the admins to change my user name to my real name "Omid".

So, don't get confused:

Omid = 2Old2Care ​

Cheers |8)|