I do not like green cast and ham - 10x alpha redux (2 Viewers)

[Steve C]

1. Color perception of mixed frequencies is not in 1:1 relationship with pure spectral values (see below).
2. Each human has a different spectral sensitivity, which were averaged when 'standard' sensitivity functions were first derived.
3. Source lighting is not standardized or controlled except in a laboratory.
4. Photographic results vary with the algorithms used in different cameras.
5. (etc.)

Gijs' and Allbinos' spectra show isolated (i.e., pure) frequency responses (in 5 nm bins), and they also differ.
Photos show pictures of many frequencies integrated by camera algorithms.
Screen displays render colors differently (mine happens to be an Apple Cinema).
Binoculars couple to observer's eyes, all of which are different, and result in different perceptions.

I don't happen to see green in any of the photos shown above. That doesn't mean that I wouldn't see a green bias if I were to look through different Zeiss/Swaro binoculars — or it might be a blue bias, or reddish. That also doesn't mean that you would see the same color bias as I do when looking through identical binoculars, and all bets are off if we're looking through different binoculars.

Then, of course, we haven't even considered 'powers of suggestion,' and 'perceptual adaptation' (i.e., color constancy).

My conclusion is that it's a good thing there's more than one brand to choose from. :smoke:

Ed

I'm on board with Ed here. I do not see green. There is a slight...ever so slight... dimness to the outside members of the three photo picture, but it is ...to me...very slightly yellowish. I'm not too sure whether it is real or imaginary.

As for a dumb question, what is the actual color of the background? That color is what I see in the photos.

 

[Gijs van Ginkel]

Henri, post 29,
You have done a lot of work, but all your pictures do not show any green to my eyes it is all blue or grey blue and again I do not see any greens in the SF or HT or FL how hard I tried.
Gijs

 

[David in NC]

Every photo Henry did has a greenish tint. It is easily seen. Maybe it comes from the fluorite glass Zeiss uses to control CA. Fluorite is green.

So is Kryptonite:

 

[birdrousta]

On my monitor at the office, which is a decent one, I did not see the difference in the thumbnails until the very emphasized one was posted this morning. That monitor is turned up rather bright and I use it under fluorescent lighting. I am able to see it in the full sized crops, but not in the "native" image (both pair of binos photographed looking through.)

On my tablet at the house, a Samsung with an IPS (not amoled) display, the color shift was immediately evident. Slightly in the thumbnails but very clearly in all of the full sized images.

 

[[email protected]]

Henri, post 29,
You have done a lot of work, but all your pictures do not show any green to my eyes it is all blue or grey blue and again I do not see any greens in the SF or HT or FL how hard I tried.
Gijs

You might be color blind for the green spectrum.

 

[David in NC]

I see a slight difference, but couldnt swear to it being green

Perterra and I are in the same boat on this...my perception also.

 

[[email protected]]

So is Kryptonite:

That is cool. I wonder if you can buy a piece any where on Earth or would you have to go to Krypton to get a piece?3

 

[cyclist]

I see what subzero sees: greenish blue, blue, greenish blue. This is true on three different monitors and on my retina display apple air. To my perceptual system the difference is not that subtle.

 

[Julian61]

I'll add my pennyworth to this thread - slightly greenish on left, slightly more greenish on right (but both predominantly blue), blue with purple in centre. Can we only understand what others see in a relative dense? Scientific description can give something objective but as soon as description becomes personal, subjective random factors multiply. For me a lens's colouration is relative to my normal sight which could be anything against others' vision. This has a metaphysical edge to it ... or am I just BS-ing?

 

[Troubador]

Every photo Henry did has a greenish tint. It is easily seen. Maybe it comes from the fluorite glass Zeiss uses to control CA. Fluorite is green. I have had many Zeiss FL's in the past and I have always observed a very slight green tinge and in Leica's and Nikon's I have always seen a slight reddish tinge color cast and really just thought that was a characteristic of that brand. The Leica's have a warm reddish color saturated image. That is one reason why I have preferred Swarovski's like Cyclist over the years because to me they had better clarity and color rendition than the others. The Swarovski's color rendition is neutral in general and they don't add any off colors. I guess when I look at a bird I want to see his "True Colors' unhindered by some greenish or reddish tint. I wonder if the members that don't see the greenish tint in their Zeiss SF's have ever compared them side by side with a neutral binocular like the Swarovski. Like Cyclist said if he hadn't compared them with the Swarovski's he would have been satisfied with the Zeiss SF's. You could become very used to a binoculars color rendition and never even realize you are not really seeing a true white but instead a greenish tinge without side by siding the binoculars. Kind of like when you think your old TV has a great picture until you get a new UHD one. Henry's pictures don't lie and the SF definitely has a slight greenish tinge.

Dennis

Henry's pictures are not of an SF.

Lee

 

[Vespobuteo]

Gijs,

Sorry I miss-typed. 440-450nm should read 540-550nm. I'll go back and correct it in my original post.

Here are some crops of the photo below which make the color bias of the binoculars more obvious. 8x54 HT is on the left, 8x56 FL on the right, the unaltered background color in the middle. As I said, not all observers will notice.

Henry

Looking at the actual RGB values in the file,
all three pics actually have the highest values in the blue channel.
So to me ALL photos have a blue cast,
and none is neutral.

Nothing green to be seen here.
Move on folks.

 

[[email protected]]

Dennis

Henry's pictures are not of an SF.

Lee

Henry was just using other examples to display the greenish tint in Zeiss binoculars but Cyclist observed it in the SF. There are other documented examples of the greenish tint in the SF's. Tobias's excellent review displays the green color bias of the Zeiss SF and even explains why you may not notice the greenish tint when looking at something white like your "bleached calcium" beach you described. Here he quotes:

"The point is: Looking at white you will hardly see any color cast, for a couple of reasons - the logarithmic nature of our vision which makes us unsensitive to brightness and colour differences in highlights, but emphasizes shadows and midtones. Plus, the fact that highlights are normally white or should be white and the brain will strongly correct for this.
So yes, your white egret will look white even with the Zeiss SF.
When a hard-boiled binocular fan complained to me about grey harriers looking grey-green observed with the SF I realized that this fit with my experience -"it´s the midtones, stupid" - I really resent to watch the brown-grey bark of my apple trees with the Zeiss SF, they look weird, and my red bird house just looks subdued in colour, as red is weakened by the complementary colour cast of the SF.
Our vision is optimized for shadows and midtones, here we can discern much smaller differences in brightness and colour casts. So I zoomed into the center of the images to find a uniform patch and get rid of vignetting, and then lowered the brightness, just that white would be mapped to a middle grey. I did not touch colour, just reduced brightness , this makes colour casts more visible."

Here some pictures from his review showing the green casts of the Zeiss SF compared to other binoculars he tested. Also, here is the link to the review.

http://www.greatestbinoculars.com/allpages/reviews/shootouts/shootoutpremier8x42s/8x42shootout.html

 

[Gijs van Ginkel]

Cycleguy, post 20,
I promised to come back to your question with regard to the color definition of the SLC and the Companion as compared with the EL. When I make an overlay of the transmission spectra of these binoculars, the color definition of all three looks pretty much the same.
Gijs van Ginkel

 

[elkcub]

Well, looking at the photos (including Henry's most recent) on different screens:

• I don't see the green cast on two different uncalibrated laptop monitors (on one of them I see a decidedly red-ish cast on both sides)
• I do see the green cast with a colour-calibrated Ezio monitor
• I also see a green cast, though less so, on an iPhone 4S screen.

I'd be interested to know if Ed's screen is colour-calibrated.

...Mike

Henry/Mike,

I don't see green on either side of Henry's last pic, using either the cinema computer display or iPhone 4S (which both look the same to me). The center square has a blue cast, but if I cover the left and right sides to eliminate edge comparison, the blue then becomes gray.

Unfortunately, the eye responds in an integrative/holistic way to all the frequencies thrown at it, not just to a dominant frequency in the transmission spectrum.

Ed

 

[Binastro]

Lee,
Don't complicate things with factual statements.

Any volunteers for the Krypton journey?

Plate window glass was green, so were bottles usually.
Old and some new magnifying glasses are green.
This is best seen looking edge on.

Broadhurst Clarkson used green glass often in WW2. The optician went out collecting broken glass from plate glass windows littering the streets and used these for eyepieces etc.

I am good at star colours, but not at bird colours. It is what you are used to.
I was also very good at fabric shades.
But not good at very faint planetary contrast.
Partly inherent, partly training.

Incidentally, Horace Dall had a very large piece of glass that was his optical flat. Very flat.
I immediately suspected thorium glass from its colour. It was high content thorium glass. It sat for years on his workbench, but he didn't move it, when I pointed it out. At his age it didn't matter.

 

[Gijs van Ginkel]

Dennis, post 52,
You quote Tobias here and I disagree with you and with what Tobias writes here. You can very well see color differences a binocular produces by looking with one eye to a white surface and with the other eye through the binocular to that white surface (provided that both your eyes have the same color response, but that can easily be checked).
Gijs van Ginkel

 

[Vespobuteo]

Henry was just using other examples to display the greenish tint in Zeiss binoculars but Cyclist observed it in the SF.

Henry photos are all high in blue, and the middle "reference" is a blue-monster.
Just look at the RGB values in the file.
It's about 2000 Kelvin off in correct white balance.

To many errors on the way, light temperature, cameras, bad LCD screens, eyes, psychology.

People are fumbling in blindness when it comes to colors.

 

[elkcub]

Well, looking at the photos (including Henry's most recent) on different screens:

• I don't see the green cast on two different uncalibrated laptop monitors (on one of them I see a decidedly red-ish cast on both sides)
• I do see the green cast with a colour-calibrated Ezio monitor
• I also see a green cast, though less so, on an iPhone 4S screen.

I'd be interested to know if Ed's screen is colour-calibrated.

...Mike

Henry/Mike,

I don't see green on either side of Henry's last pic, using the cinema computer display or iPhone 4S (which both look the same to me). The center square has a blue cast, but if I cover the left and right sides to eliminate comparison, the blue then becomes an indistinct gray.

The eye responds in an integrative/holistic way to all the frequencies thrown at it, not just to a dominant frequency in the transmission spectrum.

The only binocular I ever owned that maintained a distinct (and disagreeable) color property was an 8x32 LXL. Other than that, if there were color-cast differences they weren't strong enough for me to notice.

Ed

 

[[email protected]]

Dennis, post 52,
You quote Tobias here and I disagree with you and with what Tobias writes here. You can very well see color differences a binocular produces by looking with one eye to a white surface and with the other eye through the binocular to that white surface (provided that both your eyes have the same color response, but that can easily be checked).
Gijs van Ginkel

Yes, but your eyes and brain don't work that way. Your eyes each send a color signal to the brain and the brain processes the color based on both signals it receives just as both eyes are necessary for depth perception. You would not use one eye when you use your binoculars would you? Many peoples eyes also vary in how good they process color. In fact in this thread a few people have said they are less proficient at detecting colors in one eye. Using your eyes as a test for whiteness is introducing another error into the formula. As Chosun says:

"All I have to do now is figure out how all of that relates to my two different colour cast seeing eyes (one golden orangish, the other bluey-greenish), my transition lens eyeglasses and Mr Magoo-like myopia!"

And here is a thread on how people see different colors with each eye:
https://www.physicsforums.com/threads/color-difference-between-left-and-right-eyes.493556/

 

[henry link]

OK, I just made more photos using the same northern skylight with an effort to improve the neutrality of the background. I don't remember what I did about white balance in the old ones, but this time I just set the camera white balance to auto. The background is white, underexposed to reduce it to a medium gray to increase color saturation. Unfortunately I don't have an SF or HT for comparison this time, so the 8x56 FL will have to stand alone. The crops show unaltered background color on the left, change in color from transiting the 8x56 FL on the right.