Join for FREE
It only takes a minute!
Zeiss - Always on the lookout for something special ‚Äď Shop now

Welcome to BirdForum.
BirdForum is the net's largest birding community, dedicated to wild birds and birding, and is absolutely FREE! You are most welcome to register for an account, which allows you to take part in lively discussions in the forum, post your pictures in the gallery and more.

Easy Eye Alignment: beyond Exit Pupil size?

Reply
 
Thread Tools Rate Thread
Old Sunday 23rd June 2019, 21:49   #1
Tomly
Registered User

 
Join Date: Oct 2018
Location: Minnesota
Posts: 35
Easy Eye Alignment: beyond Exit Pupil size?

I previously owned and sold a pair of Nikon E 8x30 porros because (while the view was quite satisfying) I was often annoyed by kidney-beaning/blackouts.

With that in mind, I have been casually hunting around for a deal on a secondhand 7x42 to get that big exit pupil. Jumping up to a x42 obviously brings a weight penalty compared to 8x30 - so Iím just wondering if there are any other optical traits that impact kidney-beaning/ease of view beyond the exit pupil size?

My Nikons seemed particularly touchy to me, but Iím not sure if thatís really justified .
Tomly is offline  
Reply With Quote
Old Sunday 23rd June 2019, 23:03   #2
NDhunter
Registered User
 
NDhunter's Avatar

 
Join Date: Mar 2009
Location: ND
Posts: 4,047
I think this issue is usually about how the binocular fits your face. Some users have deeper eye sockets,
and some don't. This does get back to eye relief and how it relates to each person, and how they learn how
to get along with it.

I don't wear glasses, and have not found a binocular that I cannot use. Some that are sorely lacking in eye
relief do not pass my keep test however. "Life is too short to have a binocular that you cannot actually use
and enjoy."

Jerry

Add: The binoculars pictured were recommended by Dennis, so take his recommendations for
what they are worth....
Attached Thumbnails
Click image for larger version

Name:	Zoomies.png
Views:	24
Size:	87.2 KB
ID:	698389  

Last edited by NDhunter : Sunday 23rd June 2019 at 23:17. Reason: Add
NDhunter is offline  
Reply With Quote
Old Sunday 23rd June 2019, 23:23   #3
WJC
Registered User
 
WJC's Avatar

 
Join Date: Jul 2005
Location: Twin Falls, Idaho
Posts: 2,276
Quote:
Originally Posted by Tomly View Post
I previously owned and sold a pair of Nikon E 8x30 porros because (while the view was quite satisfying) I was often annoyed by kidney-beaning/blackouts.

With that in mind, I have been casually hunting around for a deal on a secondhand 7x42 to get that big exit pupil. Jumping up to a x42 obviously brings a weight penalty compared to 8x30 - so Iím just wondering if there are any other optical traits that impact kidney-beaning/ease of view beyond the exit pupil size?

My Nikons seemed particularly touchy to me, but Iím not sure if thatís really justified .
Eye POSITION is critical.

Bill
Attached Thumbnails
Click image for larger version

Name:	Screen Shot 2019-06-23 at 5.17.15 PM.jpg
Views:	47
Size:	293.4 KB
ID:	698391  
__________________
ďSocialism only works in two places ... Heaven, where they don't need it and Hell, where they already have it.Ē ó Ronald Reagan
WJC is offline  
Reply With Quote
Old Monday 24th June 2019, 00:07   #4
[email protected]
Registered User

 
Join Date: Jul 2005
Location: Colorado
Posts: 1,857
Kidney Beaning is caused by the eye relief of the binocular not matching your eyes. A lot of binocular's eye cups don't screw out far enough to match the eye relief and many are so small(like compacts and Habicht's) that they go too far into you eye socket and of course as Jerry says it depends on how deep your eye sockets are and how big in diameter they are also. A bigger exit pupil like a 7x42 gives you will help because it gives you a bigger cone of light to match your eyes. So it is easier to get the bigger cone centered over your eyes. A lot of people change their eye cups or add winged eye cups in an attempt to get the eye relief to match the eye cup length of their binoculars. I figure that no eye cup is going to match your facial contours perfect so I cup my hands around the eyepieces and adjust the eye relief by resting my hands on my forehead thereby adjusting the eye relief in that method. You might try that with your Nikon E 8x30 before you get rid of it. The only binoculars I have that really fit me well enough to rest the eye cups directly on my eye sockets are my Swarovski SV's.
denco@comcast.n is offline  
Reply With Quote
Old Monday 24th June 2019, 07:23   #5
Troubador
Moderator
 
Troubador's Avatar

 
Join Date: May 2012
Location: Sheffield
Posts: 9,084
As Jerry and Dennis have pointed out, black-outs and kidney beans and similar phenomena are caused by the interplay between eye relief, eyecup design and your facial structure plus the additional complications if you wear eyeglasses. As Bill points out, while larger exit pupils make life easier, correct eye position makes life easier still.

Lee
Troubador is offline  
Reply With Quote
Old Monday 24th June 2019, 16:19   #6
Tomly
Registered User

 
Join Date: Oct 2018
Location: Minnesota
Posts: 35
Thank you for the replies everyone! Is there an eye relief amount that many/most non-eyeglasses wearers find comfortable?
Tomly is offline  
Reply With Quote
Old Monday 24th June 2019, 16:48   #7
Troubador
Moderator
 
Troubador's Avatar

 
Join Date: May 2012
Location: Sheffield
Posts: 9,084
Tomly

Eye relief is the distance from the top lens of the eyepiece to the place where the full field of view can be seen in focus. This does not take any account of the design of the eyecups which can 'rob' you of some of this ER due to the distance of its rim from the top lens of the eyepiece. So although one could say that 17mm or 18mm of ER should be OK, some folks with some binos (or rather, with their eyecups) may find this doesn't work for them. And don't forget that the eyecup can deliver your eyes to a place beyond or in front of the ER position. I am an eye glass wearer and in theory should have all my eyecups screwed all the way down but with some binos I need the eyecups a notch upwards and if there is no convenient notch I place rubber o-rings under the lip of the eyecups to lift them up to the required position.

It isn't simply the case that bino makers get this wrong, its just that there is an infinite number of facial shapes. Some folks have sunken eyes, some have bulging eyes, some have broad and protruding noses and others have slim ones, and don't lets get into eyeglass lens and frame designs.....

Lee
Troubador is offline  
Reply With Quote
Old Monday 24th June 2019, 17:58   #8
Tomly
Registered User

 
Join Date: Oct 2018
Location: Minnesota
Posts: 35
Thanks, Lee. Very helpful!
Tomly is offline  
Reply With Quote
Old Monday 24th June 2019, 18:42   #9
[email protected]
Registered User

 
Join Date: Jul 2005
Location: Colorado
Posts: 1,857
"It isn't simply the case that bino makers get this wrong, its just that there is an infinite number of facial shapes. Some folks have sunken eyes, some have bulging eyes, some have broad and protruding noses and others have slim ones, and don't lets get into eyeglass lens and frame designs....."

That is exactly the problem with eye relief and eye cup design. Everybodies face is different in shape. What they need is some type of automatic eye cups that measure your facial contours with a laser and then electronically come out to conform to your face perfectly with perfect eye relief.

Last edited by [email protected] : Tuesday 25th June 2019 at 13:59.
denco@comcast.n is offline  
Reply With Quote
Old Tuesday 25th June 2019, 04:01   #10
Steve C
Registered User
 
Steve C's Avatar

 
Join Date: Jun 2007
Location: Klamath Falls, Oregon
Posts: 3,564
Once you start seriously looking for binoculars, you will go through more than one, more than likely. I have been saying for a long time now that the way a binocular fits your hands, face, and eyes is much more important in ultimate user satisfaction than anything else. Just because a 7x42 will have a big exit pupil. that does not guarantee easy eye placement. Just because a little 10x25 will have a small exit pupil, that does not necessarily mean it will have poor eye placement. As a general rule, probably, but it has been amply well noted that there is no hard rule here. The only thing that matters is what works for you. Herein lies the reason for the oft stated Try Before You Buy. Like Jerry, I don't yet need glasses, so I seldom if ever come across a binocular I cannot use.

As a minor point I disagree to a small extent with Lee's comment about binocular makers not getting the eye cups right due to faces differences. Too many eye cup assemblies are too much alike for it to be a coincidence. I think the engineer sent something different to the bean counters, who promptly saved a few bucks production costs with a less expensive more readily available eye cup.
__________________
Steve

"Do what you can, with what you have, where you are". Teddy Roosevelt.
Steve C is offline  
Reply With Quote

BF Supporter 2009 Support BirdForum With A Donation

Old Tuesday 25th June 2019, 13:07   #11
PeterPS
Registered User

 
Join Date: Jan 2014
Location: Stanford and Uppsala
Posts: 700
Quote:
Originally Posted by Troubador View Post
...and if there is no convenient notch I place rubber o-rings under the lip of the eyecups to lift them up to the required position.

It isn't simply the case that bino makers get this wrong, its just that there is an infinite number of facial shapes. Some folks have sunken eyes, some have bulging eyes, some have broad and protruding noses and others have slim ones, and don't lets get into eyeglass lens and frame designs.....

Lee
An aspect of the eyecups of Zeiss Victory FL models that's rarely mentioned is that they stay put in whatever position you set them. This continuous adjustment capability, which is rather unique (does anybody know of any other models with similar eyecups?) eliminates the need for using o-rings.

Last edited by PeterPS : Tuesday 25th June 2019 at 14:06.
PeterPS is offline  
Reply With Quote
Old Tuesday 25th June 2019, 21:56   #12
[email protected]
Registered User

 
Join Date: Jul 2005
Location: Colorado
Posts: 1,857
I think the Swarovski 8x30 CL B's eye cups are continuously adjustable like that if I remember correctly. They are one of my ex's. So I can't verify.
denco@comcast.n is offline  
Reply With Quote
Advertisement
Reply


Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Is it exit pupil size that affects ease of alignment with eyes? whitedragon101 Binoculars 10 Tuesday 3rd July 2018 07:29
exit pupil size rivergazer Digiscoping cameras 1 Wednesday 6th January 2010 20:31
Exit Pupil Size and Relative Brightness NoSpringChicken The Birdforum Digiscoping Forum 4 Thursday 16th August 2007 04:30
Eye astigmatism / exit pupil size / sharpness APSmith Binoculars 5 Friday 2nd March 2007 18:26
Importance of size of exit pupil gunvald Binoculars 40 Thursday 25th March 2004 15:49

{googleads}

Fatbirder's Top 1000 Birding Websites

Help support BirdForum

Page generated in 0.26456594 seconds with 25 queries
All times are GMT. The time now is 11:36.