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What is more important transmission or exit pupil size as we age? (1 Viewer)

[email protected]

Well-known member
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When I had the FL 8x32 I noticed greens would pop a little bit. It wasn't a 'color cast' per se, but just an emphasis when looking at Pine trees and other greenery. I agree some people may notice this and others won't.

I've been thinking about colors a lot lately and this is due to the Nikon MHG having an obvious (to me) bias towards yellow. I noticed this initially when comparing it to the CL 8x30 which has a more color neutral image. As I began using the Nikon solely over the next several weeks the colors began to look more neutral since I wasn't comparing it anymore. However, this past weekend I finally noticed the color bias in the MHG on its own, in certain light conditions, while out birding; it just came to me without looking for it. I don't mind this at all and actually really like its distinct color tones and image quality.

While shopping for bowls and plates recently I became a bit obsessed with white dinnerware and the different shades of white. I noticed this when comparing bone china bowls and plates to regular porcelain. The bone china looked a pure white, while the white porcelain ranged from cold to warm compared to the 'true' white of the bone china dishes; some porcelain bowls looked a touch blue-gray (cold) in comparison while other pieces had a slight touch of yellow (warm) next to the bone china. The warmish toned ones looked like a creamy off-white with just a hint of subtle yellow. One of the warmer white dishes were described as 'crisp white' in the AD blurb, but they really aren't when compared to the bone china pieces.
If you did not compare these pieces with the clean/true white bone china, you would see them as just white dishes and you may not be able to see their inherent slight warm/cold tones. When looking through your binocular whites will just look white until you compare them with other bins; then you may be able to see the difference. The more neutral binos should show striking pure whites just as the Swaro CL does. I always really liked the colors in the CL, but I also find the warmish binos very relaxing and pleasing too; Ultravid, Monarch HG, Meostar all have a slight warmish image IMO. I noticed the Cabela's Euro HD had a slight hint of yellow when comparing it to my old Ultravid Plus several years ago.

I agree with Holger who mentioned in one of his reviews that a slight yellow or warm bias is just fine in binoculars since they can provide a relaxing image which can help to reduce eye strain. I'd probably have difficulty finding the review where he mentioned this and I'm not quoting him accurately, but the general thought was that a slight yellowish/warm bias can be beneficial for extended viewing.
"I'd probably have difficulty finding the review where he mentioned this and I'm not quoting him accurately, but the general thought was that a slight yellowish/warm bias can be beneficial for extended viewing."

Especially when your extended viewing is done in a cold climate!🥶
 

tenex

reality-based
Does anybody notice a color bias in the transmission of any of the binoculars?
Just to add another response, both top squares look greenish to me, the one on the right more so. The bottom squares at first struck me as very slightly reddish but I think that was just due to proximity to the others; when I mask those off, they look about as neutral as the background.

Some have suggested that (certain) Zeiss binos merely "emphasize" green objects rather than having a color cast, but looking at this chart reminds me that I'm not sure I understand a basis for such a distinction.
 

[email protected]

Well-known member
Supporter
Just to add another response, both top squares look greenish to me, the one on the right more so. The bottom squares at first struck me as very slightly reddish but I think that was just due to proximity to the others; when I mask those off, they look about as neutral as the background.

Some have suggested that (certain) Zeiss binos merely "emphasize" green objects rather than having a color cast, but looking at this chart reminds me that I'm not sure I understand a basis for such a distinction.
That sounds reasonable. That would probably help in low light perception.
 

Jessie-66

Germany
Some have suggested that (certain) Zeiss binos merely "emphasize" green objects rather than having a color cast, but looking at this chart reminds me that I'm not sure I understand a basis for such a distinction.
German Wikipedia (translation):
"Red-green vision loss or blindness affects about 9% of all men and about 0.8% of women, making it significantly more common than yellow-blue vision loss or blindness (tritanopia) or total color blindness, both of which have only a 1 in 100,000 chance of occurring."

How large are "dark numbers", slight and thus undetected color weaknesses, possibly different for different colors? Resulting hypersensitivities at the "other end" of the spectrum, a (multiple) color deficiency acts like an additional or several color filters in the overall system "ambient light with changend wave lengths (sun, twilight, dust, night) -> different light reflected from the observation object -> binoculars with "non flat" (non-ideal) transmission curve (= color filter) -> eye/retina with INDIVIDUAL visual deficiency/hypersensitivies -> brain with individual different compensations of sight". The models sided in the thread can mean little to people who do not have completely normal vision. Gijs also wrote about frequent "yellowing" (= color filter) of the eye lenses of older people. Gijs and Omid also has a hard time predicting how transmission curves will affect people with unknown color vision deficiencies and hypersensitivities.

My theory is that manufacturers should aim for a transmission curve that is as flat as possible, because the brains of many people with slight color deficiencies and resulting hypersensitivities do not even notice them in everyday life, the brain compensates for them. Binoculars with a non-ideal (non-flat) transmission curve changes the experience-based, compensating function of the brain, at least during short observations "color casts" occur. (The change of the color temperature of TVs is not noticed after a longer time. Color cast in long-time observation with bins???) In the case of hypersensitivity (perceived colour cast), binoculars with different transmission curves should be tested in different observation situations / ambient light. For instance Zeiss/Swaro (cool) versus Leica/Meopta (warm). But this is only a theory of mine, I have no test bins and subjects available, I have no known color weakness.

When members of the forum generalize an individually perceived "color cast" of binoculars for other humans (or generalize models developed with and for normal sighted people), I need lots of popcorn. ;-)
 
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Gijs van Ginkel

Well-known member
Jessie-66, post 124,
You expressed it very nice, actually I am probably unable to predict with great precision how transmission curves will affect people with color deficiencies and hypersensitivities. By the way did you decide to buy the Leica-Kern binocular?
Gijs van Ginkel
 

Jessie-66

Germany
Hello Gijs, here are far too many beautiful binoculars - but far too little money. I have gratefully taken note of your detailed explanations in the other thread regarding Leica-Kern's porro bins. In order not to prolong threads unnecessarily, I sometimes express this only by 1 "Like". But I just don't think you and I have the same taste in handbags. :) :) :)
Vriendelijke groeten. Jessie
 

Gijs van Ginkel

Well-known member
Jessie-66, post 126,
Even my wife does not like the beautifully crafted Kern "handbag"and actually I was really surprised that women liked them at all as handbags.
Gijs van Ginkel
 

Jessie-66

Germany
Giijs, post 127,
In the past, Germany even had handbags (without binoculars) that were modeled after the quivers/feeder eels of binoculars. I have seen only pictures.
There is another interesting question: What happens to the perception of lateral CA by people with colour deficiency/hypersensitivity in connection within daily life experienced and so compensating brain?
Jessie
 
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Gijs van Ginkel

Well-known member
Jessie-66, post 128,
The most probable reaction by that person I can think of is: why for heavens sake do I want to buy that binocular, my life is already colorful enough and I do not want a 24 hour head-ache.
Gijs van Ginkel
 

Jessie-66

Germany
Gijs, I specifically meant whether and with which specific color weakness these people perceive CA stronger or weaker. In the forum, CA of one and the same binoculars members judge differently, some probably almost do not notice CA. Therefore, the serious question, consideration. I see lateral CA as green and violet/purple edges of dark objects with lihgt backligt (overcast sky). Correlations to color weakness seem possible to me. Jessie
 
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Gijs van Ginkel

Well-known member
Jessie-66, post 130,
I find your question difficult to answer, since the total color impression of a binocular image is, in the ideal case not very different from the one without looking through binoculars. In your example with color aberrations it will be different for everybody depending on the kind of color weakness/deviation of your eyes and you show your point fairly convincingly by your description of lateral CA as green and my eyes do not (often more bluish in my case) and I have no color deviation in my eyesight according to my eyedoctor. So, I think you are right that there can be an effect of color weakness on binocular observations.
Gijs van Ginkel
 

Jessie-66

Germany
Gijs, first of all, thank you for your answer. To be precise: In normal nature observation I see CA violet. On the half moon, lime-green on the round side. I test the CA of binoculars among other things on an almost black satellite antenna (SAT mirror). There I see CA lime-green on one half and violet/purple on the other. Purple on the half that lies at the edge of the binoculars when panned horizontally. Backlight of SAT antenne during tests mostly light gray overcast sky. This probably explains my observation only of lime-green CA on the moon: Violet against an almost black background (night skies) is hardly visible. On sunny days with blue skies I perceive CA little and mostly lime-green. Purple against a blue sky is difficult to see.
I understand very well your interest and work on transmission curves and human colour perception: A fascinating and probably infinite topic, if one include colour weaknesses and hyper-sensitivities of humans. Jessie

Edit: Text added.
 
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Jessie-66

Germany
An idea for readers of my articles who perceive colour casts or/and CA on binoculars more intensely:
Imho, it may be also the case that the brain "switches" to more sensitivity for other colours (wavelengths) for better individual detail recognition in the case of diagnosted and unknown, little and therefore undiagnosted colour vision deficiencies/weakness/hypersensitivities, and a colour cast should be accepted for this. I read that some blind people develop particularly good other senses for compensation.

Or the opposite is the case, the colours of the individual colour deficiency should better be emphasised by the binoculars. However, optical binoculars are passive systems, nothing can be amplified, only other parts of the spectrum are filtered, attenuated. See transmission curves. If the colours (better wavelength's range) of the perceived colour cast is attenuated/filtered, the colour cast will certainly become less. But what happens to the perception of details?

One could now try out the individual detail recognition with different binoculars with qualitatively different transmission curves under different ambient light (sun, twilight, overcast skies, mist) on test pictures, print them out for this purpose and look at details from some distance with different binoculars. Experiments with different coloured natural detailed observation objekts are also possible. Perhaps there will be interesting, very individual findings.

Some test images for detection of color weakness known in Germany. Similar websites with test images certainly exist in other languages with understandable explanations for such pictures.
Press right button with blue text under the pictures.

Maybe this idea will help some readers? I would appreciate feedback, also by PM.
Jessie

Edit: Text added.
 
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Gijs van Ginkel

Well-known member
Jessie-66, post 133,
Your suggestion with the examples given seems to me a very good method to check the eye's response to the overall color definition of a binocular image, much better than trying to explain it with words, since it shows directly the eye-binocular response on colored objects. It takes into account the particular properties of the eye of the observer which differ from person to person. Very practical and useful.
Gijs van Ginkel
 

Jessie-66

Germany
Thank you Gijs. The confirmation of my idea went down like oil. Maybe people with hypersensitivities ("color cast") and multiple binoculars will write their individual results and findings sometime? Jessie
 

John A Roberts

Well-known member
Australia
In relation to the link in Jessie’s post #133, the corresponding English language Wikipedia article on Colour Blindness can be found at:
https://en.wikipedia.org/wiki/Color_blindness

It includes an interesting table that shows the various types/ degrees of colour deficiency in humans
The table may in a small way help put into context, the differing impressions between some individuals,
as to the colour characteristics of particular binoculars


John
 

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[email protected]

Well-known member
Supporter
In relation to the link in Jessie’s post #133, the corresponding English language Wikipedia article on Colour Blindness can be found at:
https://en.wikipedia.org/wiki/Color_blindness

It includes an interesting table that shows the various types/ degrees of colour deficiency in humans
The table may in a small way help put into context, the differing impressions between some individuals,
as to the colour characteristics of particular binoculars


John
Interesting! So all these members that have been saying the Zeiss have a green color cast could be color-blind. It sounds reasonable really!
 

[email protected]

Well-known member
Supporter
Here is a color-blind test to take. I especially want all those members that see a green cast in Zeiss binoculars to take it and report your results. I have perfect color vision. It only takes 2 minutes. I see no green cast in Zeiss binoculars.

 
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Jessie-66

Germany
Dennis, that's a good idea. I would like to point out that imho slight color weaknesses are hardly detected by such tests. Happy new year to all readers. Best wishes. Jessie
 

Troubador

Moderator
Staff member
Supporter
Did the test Dennis. I don't see a green cast in Zeiss binos and the test said I have normal colour vision.

Lee
 

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