• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Veiling glare: a bird club's unanimous verdict on my 8x32 EL FP (1 Viewer)

the image through all binoculars is ‘ flattened’ or less 3D and therefore less natural compared to the naked eyes. I remember in the beginning noticing this with one of my Leupold bins. Our eyes adjust to viewing through binoculars.

The difference between the images in binos with field flatteners and binos with no field flatteners is very subtle and isn’t noticed by lots of people perhaps because eyes are adjusted to viewing through binoculars in general.
I agree 100% most people, novices or even people who’ve been observing for decades don’t notice the three dimensional Image quality in comparison to most roofs. But an interesting fact is once pointed out and shown what to look for , they immediately pick it up. And they could notice it every time I hand them a Porro. More interesting is they forget about it and even though they like it when pointed out , unless they’re more optics aficionados it wouldn’t make them run out and buy a porro. The birders and nature observers are much less interested of course than the optics guys/gals.
Allbinos and some people here in the forum claim the Monarch HG doesn’t seem to actually have field flatteners. They’re looking only at the blurry edges of the field and finding some curvature there too. But it does indeed contain a field flattener as advertised on the bino itself. There aren’t any obvious bending lines in the image.
I find the field flatteners in the MHG just not as effective than some of the others, EDG, SE, SV etc. etc. There’s not much bending but there is quite a bit of noticeable edge softness, if you look for it.
It’s striking to me now when I notice the flattened image; I’m never looking for it. Just last week I spotted a Song Sparrow singing on a pile of rocks near a construction site. Through the Nikon I noticed the pile of rocks looked very flat, 2 dimensional and just like a paper photo. It’s easier to notice the flat image looking at piles of mulch, maneuver, sand, rocks, etc.
 
I find the field flatteners in the MHG just not as effective than some of the others, EDG, SE, SV etc. etc. There’s not much bending but there is quite a bit of noticeable edge softness, if you look for it.
it’s definitely not sharp to the edges like Swarovison or some of the new Super alphas. This is not an issue for me since the fov is so wide and the area of sharpness is large enough that it provides an immersive view IMO.

I don’t notice any rolling ball in my MHG thankfully. I don’t think I’d still have it if it was evident.
 
Last edited:
Obvious to most here, perhaps, but I was surprised to see that veiling glare in binoculars is also a much discussed topic in astronomy. The Cloudy Nights site moderator provided an interesting way to make a lens shield to reduce glare when viewing the moon and night sky (first 2 posts below). The third post below provides a Zone of Glare illustration for selected porro vs. roof models, the latter including 2 NL models. Lastly (4th post below), one person briefly discussed a possible standardized way to test various binoculars models for glare (post 31, also see post 32 re: glare).

Glare and Objective Light Shields - Binoculars - Cloudy Nights
Lens hoods For binoculars - Binoculars - Photo Gallery - Cloudy Nights
Swarovski NL Pure 12x42, your experience? - Page 2 - Binoculars - Cloudy Nights
Swarovski NL Pure 12x42, your experience? - Page 2 - Binoculars - Cloudy Nights
 
Last edited:
Veiling glare is discussed by astronomers too, but mostly by the optics-obsessed among us. The full Moon is an excellent target for testing optical quality, I call it the "torture-test" for evaluating cleanliness of optics. All will be revealed! There is nowhere for stray light, glare, or ghost images to hide with the bright disk against black space.

But in practice, the vast majority of astronomy viewing with binos occurs on moonless nights, looking at faint objects. The lens-hood idea there is a good one, but I doubt any of us actually implemented it for viewing at night.
 
Hume🍺 would say that the connection between field curvature and 3D effect is a matter of fact, not a relation of ideas.
No, I'm not mistaking empirical for analytic knowledge, just trying to sort out which principle could explain some people's perception of "flatness". 🍻
There aren’t any obvious bending lines in the image.
Bending lines? The issue here is field curvature, not rectilinear distortion.
I agree 100% most people, novices or even people who’ve been observing for decades don’t notice the three dimensional Image quality in comparison to most roofs.
Roofs vs Porros? The issue here is field flatteners in roofs, not stereoscopy. See, there it goes again...

Back to observations:
Through the Nikon I noticed the pile of rocks looked very flat, 2 dimensional and just like a paper photo.
And this despite MHG's relatively moderate (as noted by many) field flattener. Interesting. How much of the FOV did the pile occupy?
Switching back to the NLs I could find the stalk, but it was much less obvious through the NLs.
I'm not quite following this. What is making it more or less obvious, and how?
 
Bending lines? The issue here is field curvature, not rectilinear distortion.
Everything I read in the past about field flatteners mention how they fix or lower 'distortion'.
What type of distortion is addressed with FF? I was under the impression field curvature is not considered a distortion.

from wikipedia: "Field flattener lenses in binoculars improve edge sharpness and lower the distortion"

 
The purpose of a field flattening lens is to reduce Petzval field curvature, which is an error of focus. Rectilinear distortion is an error of magnification. Now given that field curvature is intimately related to variations in the focal length the field area of the system and magnification is determined by the focal ratio of the system it stands to reason that field flatteners will also affect rectilinear distortion.
 
The purpose of a field flattening lens is to reduce Petzval field curvature, which is an error of focus. Rectilinear distortion is an error of magnification. Now given that field curvature is intimately related to variations in the focal length the field area of the system and magnification is determined by the focal ratio of the system it stands to reason that field flatteners will also affect rectilinear distortion.
thanks ... how does the FF affect rectilinear distortion ? introducing it/making it worse or reducing it ?
 
There's no consistent relationship between field flatteners and rectilinear distortion. Flat field binoculars and telescope eyepieces can and do have various distortion profiles ranging from high angular magnification distortion combined with low pincushion distortion (Fujinon), to low AMD combined with moderate pincushion (Canon), to pincushion so high that it causes a reversed AMD that stretches rather than compresses objects in the outer field (Televue Nagler.)

Also the correction of field curvature and off axis astigmatism in flat field designs varies. Some correct both well (Swarovski), some correct astigmatism much better than field curvature (Nikon SE) and some only partially correct both, each by about the same amount (Zeiss SFL.)
 
Last edited:
First, I've learned so much from reading this forum -- thank you all.

I've read various posts about veiling glare and disagreements over such among some members for the identical model of binocular, and attributed sometimes merely to "differences among individuals."

I've had horrible problems at dusk with veiling glare on my dearly loved 8x32 EL FP's while doing daily sunset/twillight counts of northern harriers coming to a distant tall grass prairie roost. Unfortunately, because of landowner issues, access is limited and the roost is viewable only when facing westward, though not directly into the setting sun. Frankly, until the roost counts, I never realized I had such a terrible VG problem.

Over the past 3 weeks, I've asked 9 experienced members of my bird club to view the roost through my EL's at roughly the same time of day. After they adjusted my EL's eyecups/diopter for their eyes, there was unanimous concurrence over the EL's disturbing VG. However, like them, I certainly saw VG through their binoculars too, though for some models (e.g., 8x42 Nocitivids), it was noticeably less pronounced.

My takeaway -- perhaps all too obvious to most of you-- is that while differences between individuals can account for a lot of things optically, seeing VG under the above-stated conditions is not one of them for a particular pair of binoculars. My wish is that VG could somehow be quantified under the conditions stated above for a wide array of alpha binoculars so that a consumer could better gauge their suitability. Thanks for listening.
Owl:
I spent some time reading all of the posts on this thread, and yours tries to tell everyone how poor the Swarovski EL is.
Off lighting can be a tricky thing, and your experience may be true. The thing is that most do not always use the binocular when
these things are present.
I suppose I should mention that the 8x32 EL is the sales leader of the premium models, and has been for over 20 years.
I wonder how you like the binocular otherwise ? :)
Jerry
 
Owl:
I spent some time reading all of the posts on this thread, and yours tries to tell everyone how poor the Swarovski EL is.
Off lighting can be a tricky thing, and your experience may be true. The thing is that most do not always use the binocular when
these things are present.
I suppose I should mention that the 8x32 EL is the sales leader of the premium models, and has been for over 20 years.
I wonder how you like the binocular otherwise ? :)
Jerry
Sorry for any misunderstanding. I dearly love both my early EL's and later SV 8x32's (see post 14 of this thread) except for the VG.

I continue -- perhaps naively and foolishly -- to hope that someone here comes up with an simple, ingenious (outside the box), cheap solution that addresses VG for existing binocular models in settings like the harrier roost.

Although not addressing a VG problem, I admired the ingenuity of a guy on the Nikon site who heavily 'customized' his binoculars to meet his personal needs.
Barrel extensions for the Nikon Monarch 7 10x30
Not pretty, but it solved his problem. Damn the appearance as long as it works.


Quote Reply
Report
 
Last edited:
There's no consistent relationship between field flatteners and rectilinear distortion. Flat field binoculars and telescope eyepieces can and do have various distortion profiles ranging from high angular magnification distortion combined with low pincushion distortion (Fujinon), to low AMD combined with moderate pincushion (Canon), to pincushion so high that it causes a reversed AMD that stretches rather than compresses objects in the outer field (Televue Nagler.)
Yes that is what I meant, I did not mean to imply a consistent relationship, merely that field flatteners modify the distortion profile of an optical design.
 
We've had entire threads devoted to the points just mentioned regarding field flatteners and distortion, and once again it somehow seems impossible to maintain focus on a single question like what makes a flat-field view look "flat" to some, so I'm content to drop it and let this thread get back to veiling glare.
 
it’s definitely not sharp to the edges like Swarovison or some of the new Super alphas. This is not an issue for me since the fov is so wide and the area of sharpness is large enough that it provides an immersive view IMO.

I don’t notice any rolling ball in my MHG thankfully. I don’t think I’d still have it if it was evident.
I agree!
Regarding the clarity on the edges of the Monarch HG 8x30 I can say that the edges are slightly softer than the center but with a gradual decrease (I would say similar to Leica Ultravid) not with such an obvious difference! It has a very pleasant visual field of view!
On the other hand, the difference between edges clarity and center clarity of the old Monarch 7 is very steep, I can even say annoying because you see it very obvious (I would say similar to the Nikon E2 8x30)
 
Last edited:
Owl:
I spent some time reading all of the posts on this thread, and yours tries to tell everyone how poor the Swarovski EL is.
Off lighting can be a tricky thing, and your experience may be true. The thing is that most do not always use the binocular when
these things are present.
I suppose I should mention that the 8x32 EL is the sales leader of the premium models, and has been for over 20 years.
I wonder how you like the binocular otherwise ? :)
Jerry
Exactly what I was thinking 🤔. I have two of these 8x32EL’s and both perform as good and or better than many others I have in off lighting conditions. I was thinking at first it was an individual thing with this specific binocular which would make sense, until he added his other nine observers over three weeks. That’s when I came to the idea he’s not an EL fan, or at this point he may have a less than stellar unit.

Paul
 
Right now I can see very well without any glare, just a very slight loss of contrast, Monte Masuccio in the center right. (NL 10x42)
 

Attachments

  • 20230309_163731.jpg
    20230309_163731.jpg
    1.6 MB · Views: 49
Last edited:
Paultricounty:

As I've stated ad nauseam (e.g., posts 14,52) , I love my 8x32s (I have both old EL's and newer SV's) -- except for the horrible VG under the conditions at the harrier roost site. As I noted (post #1), all of us at the roost had VG problems with their binoculars, with some brands/models clearly doing better than others.

I am very sorry that my seeing horrible VG through my 8x32's at the roost site offends you or anyone else. That was not, even for a moment. my intention. However, denialism is not in my DNA -- I hope you can appreciate that. Please read post #1 again. Thanks.
 
Last edited:
Right now I can see very well without any glare, just a very slight loss of contrast, Monte Masuccio in the center right. (NL 10x42)
Nice wide spectacular view.

Perhaps I'm wrong and someone knowledgable can correct me, but what you call a "slight loss of contrast,' I'd call obvious glare that occupies about 50% of the photo. When I get VG the sun is not even my field of view, as in the upper extreme of your photo, and yet VG essentially occupies the entire field under early evening conditions — about an hour before sunset — when looking westward with a distant dark tree line in the background
 
Last edited:
Nice wide spectacular view.

Perhaps I'm wrong and someone knowledgable can correct me, but what you call a "slight loss of contrast,' I'd call obvious glare that occupies about 50% of the photo. When I get VG the sun is not even my field of view, as in the upper extreme of your photo, and essentially occupies the entire field.
Im not sure, but, if I were there for that pic. I would take my binos down and ask myself if I was seeing these same light beams coming off the sun. If I did, thats mother nature's glare, not a product of my bino, to my mind. And I wonder if this is not the issue with the subject of glare. Do we all agree with what it is? I suspect not... Words on a computer screen arent enough.
 

Users who are viewing this thread

Back
Top