New Posts New Posts RSS Feed - Binocular View turned Black
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Check GunBroker.com for SWFA's No Reserve and No Minimum bid firearm auctions.

Binocular View turned Black

 Post Reply Post Reply   Topic Search Topic Search  Topic Options Topic Options
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 13:16
mtmander View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: April/10/2013
Location: North Carolina
Status: Offline
Points: 20
I was looking thru a binocular and when I moved a little the view turned black.  I moved/adjusted the binoculars and I had a clear view again.

I would like to know what caused this ,  the way I held the binoculars or if there is some other reason (I do not wear glasses when I look thru binoculars) for this occurance.

thanks for any input    
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 13:37
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 14321
It's because you were moving your eye out of alignment with the exit pupil diameter. The exit pupil is the round column of light exiting the ocular lens through which all the light exiting the optical system travels to your eye. It is sometimes referred to as a "virtual aperture."

If you hold any optic at arms length, you will notice small circles of light at the center of the eyepiece lens(es). This is the exit pupil. If you divide the effective objective diameter (for example, 42mm) by the optic's magnification (for example 8X), you get the exit pupil diameter in mm. For example, the exit pupil diameter of an 8X42 bino would be 5.25mm. The larger the exit pupil diameter, the further your eyes can stray from the center line of the optic before you get the black-out you observed.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 13:44
Klamath View Drop Down
Optics Master
Optics Master
Avatar

Joined: May/20/2007
Location: United States
Status: Offline
Points: 1268
Sounds like what is called a kidney bean blackout.  Called Kidney bean because the blackout is usually around the edges.  It is caused by the eye relief of the binocular not matching your eyes.  To put a point on it there is a mechanical or optical eye relief which is defined by the design, that may be for example 18 mm.  There may be, for example 14 mm of effective or usable eye relief.  That may be that for glass wearers the eye cups don't fit close enough to the lens and glass wearers can't get close enough the the ocular lens to get the fov.  For non glass wearers it usually means that the eye cup will not screw out far enough.  In either case, your eyes are not centered in a natural manner and pretty soon you find yourself looking at a  blank, black view as soon as you eyes move off your sweet spot.  You may have different results by trying the eye cups at all settings, it can be from too much or too little adjustment.

It can also happen with a small diameter exit pupil where it is hard to keep perfect eye and lens alignment.

I would not buy that binocular if it were me.

I see Ted beat me to some of this Big Smile
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 14:04
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 14321
The blackout situation Steve describes is related to your eyes being outside the eye relief but still within relatively close alignment with the center axis of the optic.

The exit pupil blackout I described occurs when your eyes are far enough outside the center-line axis of the optic laterally to be outside the exit pupil, yet may still be within the optics eye relief distance.

One or the other or both is happening, depending on which direction you are holding the bino away from and/or out of alignment with your eyes and how far.

Neither is necessarily indicative of a design flaw or problem with the optic, depending on magnitude. Move the optic far enough away from and out of alignment with your eye, and you will get the blackout with any optic in existence. However, if the eye relief is exceedingly short and/or the exit pupil exceedingly small (excessive magnification relative to the size of the objective lens system), making eye position very critical, I wouldn't buy the optic.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 15:02
mtmander View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: April/10/2013
Location: North Carolina
Status: Offline
Points: 20
Thanks,    this happened with a 10x42 binocular,  I want a 8x42 binocular.   If I understand the above a 8x will have a bigger exit pupil diameter,  so will this change the effect of the blackout ?   I know I really need to try a 8x to be sure. 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 15:30
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 14321
The 8X42 is slightly more forgiving of eye position, by virtue of a 1mm larger exit pupil diameter, but that difference isn't huge. You can also have widely varying amounts of eye relief between different brands and models of binos. So, depending on whether your issue is related to short eye relief or your eyes not being centered in the eyepieces, going to 8X may or may not make a difference. Regardless of which binocular you buy, you'll need to adjust your binos for your proper interpupillary distance (the spacing between the centers of both your eyes). You do this by moving the bino's center hinge in or out to put both eyepieces in alignment with your eyes. Then, you need to adjust the bino's eye cups in or out to put your eyes the correct distance from the eyepiece lenses to be within the optic's eye relief. The eye cups are adjustable to accommodate different people with varying face shapes and eye socket depths, and for people who do and don't wear eye glasses. Once these 2 things are done, you shouldn't have the blackout issue with any 8X42 or 10X42 bino under normal use.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 17:35
Klamath View Drop Down
Optics Master
Optics Master
Avatar

Joined: May/20/2007
Location: United States
Status: Offline
Points: 1268
Originally posted by mtmander mtmander wrote:

Thanks,    this happened with a 10x42 binocular,  I want a 8x42 binocular.   If I understand the above a 8x will have a bigger exit pupil diameter,  so will this change the effect of the blackout ?   I know I really need to try a 8x to be sure. 

One thing I have learned is never try to guess how any given set of eyes will react to any given binocular.  Designs typically shoot for some target middle of the road spec to work for most.  If you are looking, keep looking until you find one that does not blackout.  The bigger exit pupil will make that potential problem less likely, but I tend to think eye relief mis-matches are common issue with either like or dislike of a particular binocular.

This does not rule out physical damage to some degree in the guilty binocular.  People can do really stupid stuff with display models in stores if that is where this was.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 18:45
mtmander View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: April/10/2013
Location: North Carolina
Status: Offline
Points: 20
When I adjust the binocular I move the center hinge until I see a single circle , move it
in and out to make sure I have the single circle and then stop. I don't use glasses so I move
the eye cups out as far as they go and then focus the left eye
first and then the right eye.
  
Is there a better way to adjust binoculars ?     I have had 2 binoculars in the last 50 years so
I have not had a lot of experience in looking for binoculars.   I use input from these forums to get
a list of what binoculars I want to see and they try to see if they 'fit' but it is difficult to see a lot
of different binoculars.  


 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 18:50
Klamath View Drop Down
Optics Master
Optics Master
Avatar

Joined: May/20/2007
Location: United States
Status: Offline
Points: 1268
That's how you do it.  Since that's not an issue (didn't think it likely was either) the trick is to get one that matches your face and eyes.  There are very likely more model that will than won't.  The face, hands, and eye fit is probably more important than optics in the long run.

Just out of curiosity, what binocular was this you were having the problem with?  Was it a friend's or a dealer display?  What do you have you need to upgrade?

I agree that finding a good selection to spend some time with is likely the toughest thing we encounter in a search for an upgrade.  




Edited by Klamath - February/28/2014 at 18:59
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/28/2014 at 19:39
mtmander View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: April/10/2013
Location: North Carolina
Status: Offline
Points: 20
I was trying a Zeiss Conquest HD 10x42 at a store display.  I currently have a Monarch ATB 10x42
and I can not look long in these without effecting my eyes.  
I tried the McKinleys but the eye cups were too big for me. I couldn't adjust without sliding the binoculars down so they did not pinch my nose (I know the new eyecup verision will be out soon).

I use them in Montana glassing open areas , max about 1 mile, and various semi wooded areas. I have use my binoculars more in the last few years than in the past (since I retired) and I want a binocular that I can glass with without getting eye strain.   I also want a 8x42 since I shake more these days and I glass until dark.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 11:44
GBNova View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: March/08/2014
Status: Offline
Points: 4
I just bought a pair of Monarch 3s for casual use and have no real binocular experience.  I have a question that is related.  While I notice the blackout as well if the binoculars are not adjusted properly, I am also seeing a glare or a white haze that shifts around just outside of the sweetspot of the lens as my eyes shift off center even just a little bit.  I have determined it is light that is reflecting off the inside of the barrel.   Should this effect be so difficult to avoid?  Is it a reflection of the relative cheapness of these binocs?  I really have to move the binocs around sometimes to reduce it's negative impact, not even being able to eliminate it from view under certain conditions.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 11:46
GBNova View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: March/08/2014
Status: Offline
Points: 4
As a follow-up, I looked though a old pair of 7/32s that my father has and the glare effect is not a problem with those.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 16:16
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 14321
GBNova, what you're describing is veiling flare, which is indeed caused by internal reflections. Some binos have more of a tendency to show flare than others. It all depends on the design elements the manufacturer incorporated into the optic to prevent flare. Yes, more expensive binos are usually superior in controlling flare, as no expense is spared in creating exceptional optical performance, and that comes at a price. However, I've seen flare in some surprisingly high-end binos, so price isn't always an indicator of whether or not you'll see it. Even an expensive optic with great flare control can still show some flare depending on the angle of light entering the bino and the intensity of the light; for example, when looking toward the sun.


Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 16:23
Klamath View Drop Down
Optics Master
Optics Master
Avatar

Joined: May/20/2007
Location: United States
Status: Offline
Points: 1268
Internal glare should not be a problem if the interior of the binocular is properly blackened.  Sounds like your Monarch has some interior issues.  But these can be exacerbated if the eye placement is not correct for you.

I think there are two options.  First call the Nikon service department and discuss this with them.  If you bought the binocular new, you may have some recourse with the warranty.  If not new, then they have a no fault fix what's wrong fee of $25 I think.  You will also be out shipping both ways.  You check out a return through the dealer.

Nikon may be able to fix the internal issues, but they eye relief is what it is.  You might see what happens if you block side light when viewing.

Welcome to OT by the way. 
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 17:08
GBNova View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: March/08/2014
Status: Offline
Points: 4
Thanks guys. I guess what I need to determine is whether the amount I am seeing is normal for the monarch 3. I wouldn't expect to see none, but I don't know how to determine if there is more then there should be. Naturally I don't want to shell out cash for something that might be normal and for a binocular that I just bought at full price that should perform as new.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/08/2014 at 19:50
Klamath View Drop Down
Optics Master
Optics Master
Avatar

Joined: May/20/2007
Location: United States
Status: Offline
Points: 1268
Look backwards through the binocular at a well lit source.  What do you see as far as bright rings, or angles, or surfaces.

Just because it's new, it does not necessarily follow that it should perform as new for everybody. You can never tell how a particular set of eyes will react to a particular binocular.

Don't get too hard headed and go to far with it should work because it's new.  Do a little more looking in the price range. Especially if you can return it Big Smile.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: March/10/2014 at 08:35
GBNova View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: March/08/2014
Status: Offline
Points: 4

Used it a bit more on the weekend and I’ve come to the conclusion it works within designed specs.   It’s really not that sensitive to flare and I can get a clear view most of the time.  I am a highly critical person, and I usually find something “wrong” with most of the stuff I buy.

 

I looked backward though the binocs and I don’t see anything unusual and the inside looks sufficiently evenly blackened.  There isn’t much else to choose from here in store in the price range that I want to spend.  The other models that are available in the price range I do not find are built as solidly as the Nikons.  For instance the Bushnell XLTs I looked at had some build issues.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: May/29/2014 at 19:32
WJC View Drop Down
Optics Apprentice
Optics Apprentice


Joined: May/28/2014
Location: Twin Falls, ID
Status: Offline
Points: 103
Klamath wrote:

"People can do really stupid stuff with display models in stores if that is where this was."

From Ch. 12 De-MYTH-tifying Binoculars:

" . . . If they’re so sure the instrument is really shockproof, they shouldn’t mind allowing you to drop it.

 

If given this opportunity, hold the binocular chest high, with the axle at a 45-degree angle to the floor—eyepiece down—and let go. Then, while the salesperson is telling his or her boss what happened, and how badly they need their job, you can slip out the front door and go on down the street to a company that operates on solid optical knowledge, instead of showmanship. Smile


Bill

 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Similar Threads: "Binocular View turned Black"
Subject Author Forum Replies Last Post
100mm (45 degree viewing) Binocular Telescope jawaid Binoculars 2
black edges in view...paralax? tjones96761 Rifle Scopes 13
Lathe turned bullets trigger29 Reloading & Ballistics 6
My Turn to ask for Help VYD Varmint Scopes 7
Neck turning questions 8shots Reloading & Ballistics 16
SS 10X warranty turn-around ex_soldier1911 Tactical Scopes 3 1/19/2007 1:33:45 AM
silly wet scope with clear turns marks pellet Rimfire / Airgun 6 4/22/2007 7:04:14 PM
Neck Turning? richardca99 Reloading & Ballistics 20
Turned over a new leaf today nitis Rifle Scopes 7
Question about handguns and turning 21 SnowDieselTrichs Shooting 30


This page was generated in 0.422 seconds.