Comparing three 32 mm binoculars (1 Viewer)

[newfie ghost]

Here is a very typical example of how the FL suppresses the reds and make colors more or less dull. The Nikon's color saturation is great, and above all this is true for the reds.

Great example and similar to my impressions of the fl and a Nikon.

 

[typo]

Your post makes sense, David, but a handheld binocular with an objective lens of relative aperture f/4 isn't nearly diffraction-limited. You do acknowledge this, but I think it's easy to overestimate the importance of diffraction in small binoculars.

My contention is that the most relevant test would compare binoculars as they're actually used, i.e. with their full aperture stopped down only by the eye's pupil in various light intensities (i.e. not at all in low light), with imperfect centring of eye and exit pupil, etc. If a binocular's basic parameters give it greater brightness in low light but lower magnification, then surely that is what it is, and shouldn't be normalised away.

Dorian,

Yes, we all do that, but the information is only relevant to you.

We're often told that binoculars out resolve the eye, yet many here report differences in 'sharpness'. Is that resolution, contrast or something else? How do you attach significance to that? Binoculars might be an f/4 instrument but when we effectively use it at f/8 or less on a bright day the apparent resolution is closer to, or even exceeds an individuals acuity. Of course there is variability is binocular samples, but the biggest variable is the users acuity. Just using those guessed values between 60 and 100 arcseconds, someone with 20/20 (120arcsec/lp) vision would most likely find them equally sharp, but someone with 20/10 vision would readily tell them apart. It's just transferable information.

I've not found a reliable way to compare brightness. Given a few moments the eye and brain compensates for the change in light level and colour balance and tries to tell you everything's the same. Looking at a monochrome target and quickly switching pairs gives an impression, but until it's virtually dark I find it difficult to find a practical advantage of one pair over another. The exception is when the light is strongly colour biased like Lars found where colour balance rather than brightness tend to make the difference.

I usually prefer high transmission pairs, and try to find indications for it. Not because they are necessarily brighter, but often they have better contrast, which I seem to notice more.

David

 

[typo]

Your post makes sense, David, but a handheld binocular with an objective lens of relative aperture f/4 isn't nearly diffraction-limited. You do acknowledge this, but I think it's easy to overestimate the importance of diffraction in small binoculars.

My contention is that the most relevant test would compare binoculars as they're actually used, i.e. with their full aperture stopped down only by the eye's pupil in various light intensities (i.e. not at all in low light), with imperfect centring of eye and exit pupil, etc. If a binocular's basic parameters give it greater brightness in low light but lower magnification, then surely that is what it is, and shouldn't be normalised away.

Dorian,

Yes, we all do that, but the information is only relevant to you.

We're often told that binoculars out resolve the eye, yet many here report differences in 'sharpness'. Is that resolution, contrast or something else? How do you attach significance to that? Binoculars might be an f/4 instrument but when we effectively use it at f/8 or less on a bright day the apparent resolution is closer to, or even exceeds an individuals acuity. Of course there is variability is binocular samples, but the biggest variable is the users acuity. Just using those guessed values between 60 and 100 arcseconds, someone with 20/20 (120arcsec/lp) vision would most likely find them equally sharp, but someone with 20/10 vision would readily tell them apart. It's just transferable information.

I've not found a reliable way to compare brightness. Given a few moments the eye and brain compensates for the change in light level and colour balance and tries to tell you everything's the same. Looking at a monochrome target and quickly switching pairs gives an impression, but until it's virtually dark I find it difficult to find a practical advantage of one pair over another. The exception is when the light is strongly colour biased like Lars found where colour balance rather than brightness tend to make the difference.

I usually prefer high transmission pairs, and try to find indications for it. Not because they are necessarily brighter, but often they have better contrast, which I seem to notice more.

David

 

[looksharp65]

What I did with the "Nikon" images was to:
1) Darken the shadowed parts
2) Reduce the overall brightness a bit
3) Increase the contrast considerably
4) Make the color balance warmer
5) Push the hue towards purple
6) Increase the color saturation

The "Zeiss" images are less manipulated compared to the original, because my camera (a Sony DSC-H20) tends to deliver images that are a little overexposed and cold.

1) Brighten the overall image
2) Brighten the shadowed parts
3) Reduce contrast very little
4) Make the color balance just a little colder
5) Push the hue a little towards green
6) Maybe decrease the color saturation very little

I want to point out that the brighter image, in particular the shadowed areas give me an impression of significantly lower contrast. The bright and darker parts of the image are levelled where the Nikon rather emphasizes the brightness differences.

Even though I really like the beautiful image the Nikon HG delivers, I have to admit that it's tweaked towards a Technicolor style.
The FL has a more true color balance than the HG, but the Fury delivers the (by far) most natural image of these three. This is not only about color balance, but also the contrast level.

//L

 

[Dorian Gray]

We're often told that binoculars out resolve the eye, yet many here report differences in 'sharpness'. Is that resolution, contrast or something else? How do you attach significance to that?

I don't think there's a contradiction in that. Two binoculars may out-resolve the eye yet appear to have different sharpness, since sharpness depends on both contrast and resolution. The sharper binocular would have fewer residual aberrations and thus deliver a greater contrast at spatial frequencies near the eye's resolving limit.

It's even possible that one binocular would deliver greater extinction resolution when the image is greatly magnified, but lower sharpness when viewed with the unaided eye. For example, a 50 mm binocular with severe residual aberrations might deliver a mushy, low-contrast image to the eye, but when greatly boosted continue to muster some contrast at spatial resolutions beyond the diffraction-limited extinction resolution of a high-quality 32 mm binocular.

Which brings me back to my belief that boosting the image doesn't tell us a lot about a binocular's practical performance, except how it performs with a booster (which itself might be useful information). Boosting the image and examining it as the focus is adjusted does make it easier to tell which aberrations are causing image degradation (e.g. astigmatism or coma?) but that knowledge is of limited practical use.

I don't know much about the human eye, though. I suppose it's possible our eyes (and brains, as you note) differ considerably in behaviour, to the extent that different individuals would rank the sharpness of several binoculars differently.

 

[Dorian Gray]

It makes sense that lighter shadows are perceived as lower contrast, looksharp65. Non-image-forming light (flare) in the binocular spills into the shadows (and the bright areas, but there it's unnoticeable), thus brightening them and lowering contrast.

For example, a bright area might have 1000 parts of light compared to a dark area with 1 part of light, for a contrast of 1000:1. Flare might cause 5 parts of light from the bright area to spill into the dark area, lowering the contrast to 995:6, or about 166:1.

(This level of flare is about 0.5%, which applied to the dark area means 0.001 parts of light spill from the shadow into the bright area: obviously unnoticeable given the other numbers involved.)

Flare reduces saturation too, since the non-image-forming light has no particular colour, and it washes over the image indiscriminately, polluting all colours such as reds, greens, blues, etc.

Given the nature of optics, it's impossible for a binocular to actually increase monochromatic contrast or saturation compared to the original scene; it's only possible for it to degrade those characteristics less than another binocular. The only exception is when a binocular effectively filters out certain colours (say blues, in a binocular with a heavy red bias) that are more present in some areas (e.g. a blue sky) of the scene than others (e.g. a red bird), thus increasing the contrast between those areas.

I've only briefly looked through the Nikon HG L, but I think most of its high contrast and saturation comes from very low flare (and low optical aberrations) rather than red filtration, though I'm sure the latter would be visible in some situations.

 

[looksharp65]

Dorian, I agree with you for the most part. Would we dare to establish that the FLs indeed have a low contrast image? Guess there are quite a few members here that would get annoyed if we killed their darlings...

Whether the relative absence of reds in the FL's image contributes to the lower perceived contrast is hard to tell, but I believe it does have an impact. The Nikons have a very different color bias, but then there's also the saturation or color contrast that is more vivid.
The relative excess of "red light" energy transmitted will for some part outnumber the cooler light like blue and purple.
As a result, when the eye adapts to the total brightness, these colors will appear subdued.

In fact, even B/W film will show this effect. When using a yellow filter, white clouds will look more natural against a darker grey (i.e blue) sky. An orange filter will take this further, and a red filter can make the sky seem nearly black on the final copy.
http://www.ephotozine.com/article/using-coloured-filters-with-black---white-film-4828
http://www.photographymad.com/pages/view/using-coloured-filters-in-black-and-white-photography


The FL seems to modify brightness of the shaded parts of the image so the details will be rendered well above the threshold for perception. Therefore, one could argue that it handles contrast very well (apart from the straylight flaw).
As mentioned in the link, blue does reduce contrast

The Nikons rather show contrast, which means that some details in the shaded parts may get lost since they are below the threshold level for perception.
As soon as a detail is bright enough to pass the threshold, it pops out against a darker background.


//L

 

[looksharp65]

I have to confess that the Nikon's color bias is at its strongest when I use my spectacles. These are not tinted at all but there may be a hint of yellow. Used with the bins, they add a couple of percent to the warm color rendition. Tiny as the added effect must be, it seems to push the bias well above the threshold.
I was astonished to recognize this, since I almost always wear them and I reckoned that my color sense was adapted to them. Apparently not.
Without them, the binocular's color bias was still decidedly warm but not quite to the same level.

And when using visibility tinted contact lenses (blue handling tint) I must say that the Nikons were absolutely color neutral in the bright sunshine at noon today.
Once again, I was astonished to see this because it does not make sense.
When I compare the scene with my naked eyes (with contacts), the binoculars should still appear significantly more reddish, but they don't.
I guess that the weak blue tint of my contacts pushes the total color bias differences below the threshold of perception. The bias is there, but too insignificant to be perceived.

//L

 

[Dorian Gray]

I've read your comments with interest, looksharp65, but I'm hesitant to flatly say the Victory FL suffers from low contrast. I haven't had enough real-world experience with an alleged "high-contrast" binocular to reliably compare the two. I do sometimes notice distinct flare in the FL, which could surely be improved upon with a different design (of course that design might sacrifice things the FL is good at, like low size and weight with a wide field of view).

What's more, the term contrast can refer to at least a couple of things:

1. Global contrast, or macro-contrast, or the contrast of large structures (like squares on a chessboard that fills the field of view). This kind of contrast is determined by the number of air-glass surfaces, the shape and position of the lenses (in terms of whether their reflections end up in the exit pupil), the quality of the lens coatings, the design and number of stray-light baffles, etc. Global contrast is concerned with very large deviations of the light beams from their desired path, i.e. flare and ghosting.

2. Localised contrast, or micro-contrast, or the contrast of small structures (like feather detail on a distant bird, the texture of tree bark, etc.). This kind of contrast is first of all limited by global contrast, because global contrast affects everything in the view, but is further attenuated—and much more significantly so—by optical aberrations and diffraction. It's concerned with small deviations of the light beams from their desired path.

It's possible for a binocular to have high global contrast and low micro-contrast: for example, a very simple optical design with extremely good anti-reflective coatings might produce this balance of characteristics. Another binocular might have low global contrast and relatively high micro-contrast, if it had a sophisticated correction of aberrations but was poorly protected against contrast-robbing stray light.

Binoculars can have both high global and micro-contrast (e.g. alphas generally), but also often have low global and micro-contrast (e.g. supermarket binoculars).

Furthermore, there's no clear-cut boundary between the two types of contrast: as you move from very large structures to very small structures, aberrations and diffraction affect the contrast rendition more and more, while stray-light protection becomes less important. Eventually the contrast falls to zero (or a perceived zero), at which point the binocular is said to have reached its "resolution." This is the extinction resolution.

I think the extinction resolution—and certainly the extinction resolution with heavily boosted magnification—isn't as important to overall viewing satisfaction as the contrast rendition of fine details well within our eye's resolution limits.

 

[pompadour]

Ls65, your pics are a fine idea. Thanks for them, the care taken, also the comments. I wonder if the artist(e) can "be commissioned to do a Leica and Swaro” also! Each set will be worth 4,000 words |=)|. I for one will find them very useful to explain image quality and character of alphas and other models, to someone who asks. You might know that the possibility of “Zeiss brightness washout” is discussed in several recent or current Bf. threads.

 

[looksharp65]

Ls65, your pics are a fine idea. Thanks for them, the care taken, also the comments. I wonder if the artist(e) can "be commissioned to do a Leica and Swaro” also! Each set will be worth 4,000 words |=)|. I for one will find them very useful to explain image quality and character of alphas and other models, to someone who asks. You might know that the possibility of “Zeiss brightness washout” is discussed in several recent or current Bf. threads.

Thanks pompadour!
The pictures are my interpretation of what I see through the two (admittedly very different) 10x32s and as such, they are entirely subjective.
The differences are more or less exaggerated, depending on which of the sets we're talking about. But let's not forget that when looking through them, the brain will diminish the actual differences, so even then, the perceived image qualities are accompanied by a certain measure of subjectivity.

Knowing that the color sense will make an adaptation to the hue of the binocular, one has to put the question how great the differences in color representation were in the camera lenses from the seventies and eighties.
Those who used color slide film are well aware of the characteristics of the various products from Kodak, Agfa and Fuji, and how the results could be tweaked just a little by using weak filters.
Then again, I assume the projection lamp may have caused some color shifts.
Anyhow, I assume the camera lenses must have been far more consistent in their color representation than these more recent binoculars are.
And with today's digital imaging, the camera lenses don't necessary have to be extremely color neutral since some image processing almost always takes place.

//L

 

[looksharp65]

What's more, the term contrast can refer to at least a couple of things:

1. Global contrast, or macro-contrast
/----/
2. Localised contrast, or micro-contrast.

I think the extinction resolution—and certainly the extinction resolution with heavily boosted magnification—isn't as important to overall viewing satisfaction as the contrast rendition of fine details well within our eye's resolution limits.

Agreed. Using these words, the FL should have a low global contrast and a high micro-contrast. The HG might be the antipode since the apparent contrast is very high, but when boosted, its CA will cause some pretty severe light spill over the dark subjects against a bright, overcast sky.

//L

 

[pompadour]

Ls65, although what is seen - or "seen" - by an individual human is subjective, it seems there's agreement by most viewers that the image through, say, the four alphas has each a certain mix of how well it fares in the main optical parameters, and (hence or otherwise) a certain "character".

It seems to me the Zeiss and Nikon pics done by you convey this rather well, and so also perhaps will others - if and when you can - for Leica and Swaro.!

The only other similar set of pics I have seen in Bf. (so far, as a member for a few months who has done a bit of searching) are photos of an entrely white area actually taken through each of those four makes - done I think by Henry Link - to show overall colour rendition.

Re. camera lenses, I did get involved with cameras, lenses, etc. for some time long ago, but I'm afraid I cannot too easily work out the connection between the info. you give and the present matter! |:S|

 

[looksharp65]

Pompadour,
re the Leica/Swaro comparison I'm not in the position to make it. I still have the original images, so if someone else wants to use them for this purpose, I'll be happy to email them.

Anyhow, I suspect that the FL and the HG represent some kind of extremes. Perhaps a newer Swaro would be slightly more "natural" than the FL, and a Leica less "extreme" than the HG.

//L

 

[jinxin]

Try SW 10×32 swarovision,its better than all above,no questions.

 

[pompadour]

Ls65, thanks. It will of course be a bit tougher for someone else, or later, to form a set - deciding on relative settings in the image processor, etc. - than for you who recently did that for the other two. Hope someone is able actually to take photos (one view and time) through the four!

I have the same idea about the relative charater of the image through Swarovision (not having had a chance to look through one, going by what I've read), but about Leica Ultravid it seems to me that it might possibly even surpass Nikon HG/EDG at that "extreme" (having looked through both - all three actually - but not done a side-by-side comparison).

Just about to post this see I see the last, by Jinxin, and am reminded one should be on topic - the 32s. So, must add I've not looked through one in the newest ranges of L, N or S and my refs. above are not to 32s except Z.

 

[barshnik]

Try SW 10×32 swarovision,its better than all above,no questions.

Of the 32's in the start of the thread, the Vortex are the only I haven't seen. I am biased, however, since I own the Swaro 10x32 SV's, and I too think they may be the finest 32's available. No color bias under any lighting conditions that I can see, sharp from edge to edge, light gathering monsters, and ergonomically wonderful, close to perfect. Oh, and rediculously expensive for a 32.

John F

 

[looksharp65]

Ls65, thanks. It will of course be a bit tougher for someone else, or later, to form a set - deciding on relative settings in the image processor, etc. - than for you who recently did that for the other two.

Well, I simply used the "Edit" function in Windows Live Photo Gallery. I have Windows 7.

Hope someone is able actually to take photos (one view and time) through the four!

To do that, it's crucial to use manual camera settings. No Auto White Balancing and no automatic exposure control.

This general discussion about colours bias, contrast and light transmission has been continued in another thread I recently started.
http://www.birdforum.net/showthread.php?t=234596
I'm less pleased to see how few replies and views it has received so I'm bumping it from here.

 

[pompadour]

Ls65, thanks. Thought it might have been less difficult if the other two were done by you - had you been in a position to do so - as you'd remember the ajustments for the first two, for comparison, and also with the momentum.

As for the camera idea, although I suggested it, I now realise it may be very difficult to find one view and time to show the character of the bins - even each separately, leave aside the set of four - a bit like a photo of a bird vs a good field guide painting (your work analogous to the latter).

Maybe the title of this thread was too narrow to indiacte the wider scope. I've been following your other with interest - skimming over for now till there's more time to take in the info. and ideas!

 

[Sunrise64]

Here is a very typical example of how the FL suppresses the reds and make colors more or less dull. The Nikon's color saturation is great, and above all this is true for the reds.

2nd Image defiantly over saturated , in my opinion .