Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

How much eye relief for glasses?

  • Please log in to reply
18 replies to this topic

#1 Stuart W Johnson

Stuart W Johnson

    Explorer 1

  • -----
  • topic starter
  • Posts: 56
  • Joined: 29 May 2020

Posted 05 December 2020 - 01:01 PM

I had the Canon 10x32 IS. It was very good. But, I sent it back. Even with the eyecups folded, I couldn’t get the full image. They are specd at 14.5mm.

What would you consider ideal and/or minimum for eye relief for glasses wearers?

Bonus question - For a conventional 8x, which models should I be looking at?

#2 DLuders

DLuders

    Soyuz

  • *****
  • Posts: 3,807
  • Joined: 10 Apr 2017
  • Loc: Spokane, WA

Posted 05 December 2020 - 01:15 PM

15mm is usually adequate Eye Relief when wearing glasses.  Eyecrazy.gif



#3 sg6

sg6

    Cosmos

  • *****
  • Posts: 9,679
  • Joined: 14 Feb 2010
  • Loc: Norfolk, UK.

Posted 05 December 2020 - 01:16 PM

My Paradigms are specified as 16mm or 17mm, depends on which review you read. So would suggest 16mm. Not sure what the other eyepieces are. Work with my glasses.

 

Be a little careful you can go and have too much eye relief, seems the TV 32mm plossl does this and the eyerelief of those will be around 22mm to 24mm.

 

The final problem is if you get an eyepiece or whatever specified as 16mm where is that measured from?

We tend to think the top surface of the outer eyepiece lens, optical designs tend to use the optical center which is likely to be around the physical center of the lens, either single of a doublet.



#4 Stuart W Johnson

Stuart W Johnson

    Explorer 1

  • -----
  • topic starter
  • Posts: 56
  • Joined: 29 May 2020

Posted 05 December 2020 - 01:20 PM

What happens with too much eye relief? Is 20mm too much?

#5 PatrickVt

PatrickVt

    Viking 1

  • *****
  • Posts: 640
  • Joined: 20 Apr 2018
  • Loc: Vermont, US

Posted 05 December 2020 - 01:33 PM

Part of how much eye relief is necessary depends on physiological characteristics of the person.  How deep the person's eye sockets are as well as how large the person is makes a difference when it comes to eye relief.  How far the eyeglasses are placed away from the eyes on the nose makes a difference.  Some eyeglasses can be tight up on the top of the nose while others are placed farther away from the nosepieces (of the eyeglasses).  A person who has a small stature would likely need less eye relief than someone who is larger than average.  Deep-set eyes are farther away from eyeglass lenses than someone with average eyes.  

 

For me, I have found that I need a minimum of 16mm and even that isn't ideal but I can get by with 16mm.  I don't find eye relief hits the comfortable range until the 18+mm range.  

 

Each person has different requirements.

 

Patrick


  • Jon Isaacs, rodelaet and oldmanrick like this

#6 SMark

SMark

    Aurora

  • *****
  • Posts: 4,562
  • Joined: 29 Aug 2011
  • Loc: Atlanta, GA USA

Posted 05 December 2020 - 01:35 PM

Most binoculars with very long eye relief will also have adjustable Eyecups. Typically, you rotate the eye cup to match the eye relief that you need. However, in the early days of Vortex binoculars, I had one that would not sit properly against my eyes to allow me the proper eye relief. My recollection is that the eye relief was 19 mm, but the rotatable eyecups would only sit correctly right between two of the notches. So I could never get the eye relief just right. It was very frustrating and I could never hold the binocular steady. So I sold binocular.


Edited by SMark, 05 December 2020 - 11:58 PM.

  • Jon Isaacs, hallelujah and earlyriser like this

#7 Knucklehead

Knucklehead

    Explorer 1

  • *****
  • Posts: 69
  • Joined: 01 Jul 2010

Posted 05 December 2020 - 01:36 PM

What happens with too much eye relief? Is 20mm too much?

I don't think you can have too much eye relief. Not everyone who wears glasses during binocular viewing needs 20mm, or 15mm, I have some bins that only have 12mm of relief, that would be my Nikon Aculon 8x42s. For myself that is the absolute minimum relief to be able to wear my glasses.

 

Faces have different shapes and some may not be able to push their glasses as close to their eyes as I can. I can get them close enough that my eyelashes are hitting the glasses. I have a nose shaped like Bob Hope's nose, which he described as shaped like a ski jump. If your nose profile is straight down from the brow or curved outward you may not be able to get your glasses as close as I can.

 

So, in answer to your question: it all depends.


  • hallelujah likes this

#8 garret

garret

    Surveyor 1

  • *****
  • Posts: 1,679
  • Joined: 26 Jul 2009
  • Loc: Netherlands

Posted 05 December 2020 - 01:37 PM

 

What would you consider ideal and/or minimum for eye relief for glasses wearers?

How far are your glasses from your eyes?

If your glasses are thin in the centre (negative) and are close to your eyes 16mm true eyerelief is adequate.

Others need over 20mm true eyerelief. 

 

edit: PatrickVt is just ahead of mesmile.gif


Edited by garret, 05 December 2020 - 01:40 PM.

  • Jon Isaacs likes this

#9 rodelaet

rodelaet

    Gemini

  • *****
  • Posts: 3,322
  • Joined: 28 Apr 2006
  • Loc: Belgium

Posted 05 December 2020 - 01:46 PM

Part of how much eye relief is necessary depends on physiological characteristics of the person.  How deep the person's eye sockets are as well as how large the person is makes a difference when it comes to eye relief.  How far the eyeglasses are placed away from the eyes on the nose makes a difference.  Some eyeglasses can be tight up on the top of the nose while others are placed farther away from the nosepieces (of the eyeglasses).  A person who has a small stature would likely need less eye relief than someone who is larger than average.  Deep-set eyes are farther away from eyeglass lenses than someone with average eyes.  

 

For me, I have found that I need a minimum of 16mm and even that isn't ideal but I can get by with 16mm.  I don't find eye relief hits the comfortable range until the 18+mm range.  

 

Each person has different requirements.

 

Patrick

I second that. 
 

For me, 18 to 20 mm is perfect with my current model of eyeglasses. But my older eyeglasses were compatible with an eye relief of 16mm. 



#10 Lee D

Lee D

    Apollo

  • *****
  • Posts: 1,258
  • Joined: 07 Oct 2009
  • Loc: Rochester NY

Posted 05 December 2020 - 01:49 PM

TeleVue settled on 20mm as sufficient eye relief to accommodate most eyeglass wearers for their last two lines of eyepieces, the Delos and Delite. Many people don't need 20mm, but for people with deep set eyes and high nose bridges (like me), 20mm about the minimum while wearing glasses.

 

The bottom line is each person has to try different offerings and figure out for themselves how much they need.



#11 vtornado

vtornado

    Gemini

  • *****
  • Posts: 3,417
  • Joined: 22 Jan 2016
  • Loc: Northern Illinois

Posted 05 December 2020 - 01:55 PM

Are you sure you want to wear your glasses?

 

I wear glasses, and remove them when viewing.  The reason is, I usually find they are dirty and need to be cleaned, and

a lot of stray light leaks in.   I do have to use the diopter adjustments on my binos because my eyes are no where near

the same prescription.   Some binos I have found do not have enough diopter adjustment.   I have a cheapie pair and

it does not, my Pentax PCF do.   One very annoying feature is that most binoculars do not include the diopter range

in the specification, so you really have to try before you buy.

 

The question about 8x binos rest on your eyes.   I have a pair of 7x50's and my eyes no longer dialate to 7mm.

So I find the 10x50's better now.  Depending upon your eyes I would say somewhere between 8x40  5mm ep,

and 8x56 (7mm exit pupil).  Sky conditions may make a difference too.   If you have lots of light pollution,

the smaller exit pupil may darken the background sky better too.

I do find the 10's a little hard to hand hold, so I have been toying with some 8x40's. 


Edited by vtornado, 05 December 2020 - 02:00 PM.


#12 russell23

russell23

    Voyager 1

  • *****
  • Posts: 11,504
  • Joined: 31 May 2009
  • Loc: Upstate NY

Posted 05 December 2020 - 05:40 PM

If you have astigmatism you will need glasses - especially with binoculars because astigmatism is more noticeable at larger exit pupils.  I find 16mm is the minimum I need. 



#13 KennyJ

KennyJ

    The British Flash

  • *****
  • Posts: 37,959
  • Joined: 27 Apr 2003
  • Loc: Lancashire UK

Posted 05 December 2020 - 06:31 PM

I would also estimate the absolute minimum truly effective eye - relief I require when wearing glasses to be around 16mm.

 

I seriously dislike wearing glasses when using binoculars, but due to astigmatism, night - sky viewing is particularly, punishingly, painfully unacceptable for me.

 

Without my glasses, even the moon appears about 50% larger and of a totally nonedescript shape, compared with how it appears with prescription glasses worn.

 

Ditto for all stars and planets.

 

If not wearing glasses, the aforementioned 32mm TeleVue Plossl is indeed an eyepiece I own which borders on having almost "too much" eye - relief, as are two binoculars I own -- the Nikon 10x42 SE and Captain's Helmsman 7x50.

 

However, "too much eye - relief" is a problem easily overcome by the simple method of inserting "spacer washers" pushed inside the eyecups to "mate against" the inner rims of the eyepieces.

 

When eye - relief is too short ( almost always the case with older 10x - 20x binoculars ) there is no simple practical cure, apart from wearing contact lenses, and even they are notoriously difficult to "get absolutely right" when correcting for astigmatism, where a very specific alignment needs to be maintained.

 

If I "tilt" my "distance" prescription glasses by the equivalent of just 2 minutes on a clock face, the resulting image is even blurrier than when not wearing any glasses at all.

 

Kenny


  • Jon Isaacs, mooreorless, hallelujah and 2 others like this

#14 sevenofnine

sevenofnine

    Ranger 4

  • -----
  • Posts: 300
  • Joined: 16 Apr 2016
  • Loc: Santa Rosa, California

Posted 05 December 2020 - 07:54 PM

My new Nikon AE 10x50's are 17.2 mm. They are adequate with the eye cups rolled back. My Oberwerk 8x56 LW are an amazing 24 mm. With the eye cups rolled back you can see the full view with the binoculars not touching the glasses...



#15 Albie

Albie

    Fly Me to the Moon

  • *****
  • Posts: 5,442
  • Joined: 22 Feb 2005
  • Loc: Alberta,Canada

Posted 05 December 2020 - 10:53 PM

I seriously dislike wearing glasses when using binoculars, but due to astigmatism, night - sky viewing is particularly, punishingly, painfully unacceptable for me.

 

Without my glasses, even the moon appears about 50% larger and of a totally nonedescript shape, compared with how it appears with prescription glasses worn.

 

Ditto for all stars and planets.


 

 

Kenny

I feel the same way about wearing glasses with binoculars. I suppose I'll get used to it if I want the good view  . My astigmatism makes the moon look twice as wide  , same for stars, bright planets or any bright light for that matter. Bright lights get bigger/wider with fuzzy spikes . It's more noticeable at night for sure but still noticeable enough during the day to benefit from correction .


  • hallelujah likes this

#16 hallelujah

hallelujah

    Cosmos

  • *****
  • Posts: 7,997
  • Joined: 14 Jul 2006
  • Loc: North Star over Colorado

Posted 06 December 2020 - 04:37 AM

I don''t know & I don't care.  lol.gif  fingertap.gif

 

Stan



#17 John A Roberts

John A Roberts

    Lift Off

  • -----
  • Posts: 21
  • Joined: 26 Mar 2020

Posted 06 December 2020 - 06:30 PM

For a measure of the functional eye relief with particular binoculars:

 

A) Pinac (aka Canip on various sites), has updated his reviews to include the usable eye relief at: https://binocular.ch...ion/#collection, and

 

B) Roger Vine also includes the useable eye relief in his reviews at: http://www.scopeviews.co.uk

 

 

John


Edited by John A Roberts, 07 December 2020 - 03:45 AM.

  • KennyJ likes this

#18 MartinPond

MartinPond

    Fly Me to the Moon

  • *****
  • Posts: 5,854
  • Joined: 16 Sep 2014

Posted 06 December 2020 - 06:52 PM

I can get by on 15mm, but I have to push the glasses in on the nose...it's tight.

It does depend on the glasses.  

 

Many insist on at least 20mm....that's the safe bet.

 

I like about 17mm, so the eyecups shade the sides well.


  • PatrickVt likes this

#19 tmichaelbanks

tmichaelbanks

    Ranger 4

  • *****
  • Posts: 323
  • Joined: 11 Aug 2017

Posted 06 December 2020 - 06:56 PM

+1 for Pinac's notations of usable eye relief, they are a valuable resource.

 

I have compared Pinac's figures with the binoculars I own and where he states a minimum of15-16mm of usable ER I can see the hard field stops.

 

I recently bought new eyeglasses that sit closer to my eyes and picked up about 1mm of ER, so the style and resting position of your glasses is relevant.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics