• 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.

Color bias and eyesight (1 Viewer)

jremmons

Wildlife Biologist
All,

Today while setting the dioptre adjustment for my bins I noticed an odd thing, that the view through the right bino tube was much warmer in color. I assumed there was a difference between the two tubes, but then when I turned the binos around and looked through the objectives, I noticed that the color bias I'd seen was reversed. I then switched back to the occular end of the binoculars and looked through both tubes with each eye. I noticed the same thing every time: my right eye consistently shows a warmer image whereas the image from my left eye was fairly color neutral. I tried other binoculars in this same manner and the result was consistent; my right eye for some reason produces a warm color cast.

I found this really odd, and though I'm not sure how it affects the actual view through binoculars, I wondered if anyone else had noticed something similar?
 
Justin ..... I have not noticed that myself, but I do recall it being discussed a couple of times. I believe CJ had some specifics to say about. In other words, you are not the only one to experience that.. I seem to recall some saying it comes and goes.

If I can find some of those old threads, I will post the links.

On Edit:

Here is a thread to start with. It contains links to more threads.

http://www.birdforum.net/showthread.php?t=268806&highlight=Color
 
Last edited:
I have noticed that the my eyes see colors differently as well. For me my left eye has slightly more vivid colors than my right. Very small difference but the difference is there for sure.

I noticed this when comparing spotting scopes and eyepieces. The view with my left eye is just a little more pleasing as far as color goes but I'm right eye dominate and cant get comfortable using my left eye for spotting so I just live with it.

Never would have noticed this unless I got so obsessed with optics.
 
jremmons, Justin, post 1,
We discovered that students who used monocular microscopes for longer periods of time, using the same eye for microscope observations, sometimes developed differences in color vision between both eyes. We have not investigated what causes it, but it might be that the eye that was used for microscope observations had been exposed for longer periods of time to higher light intensities, which might have changed the difference in color perception. It is a guess, but I have not a better one yet.
Gijs van Ginkel
 
I've noticed this phenomena in my own eyes on some occasions. I would attribute some of the phenomena to subtle differences in the intensity of light hitting each eye, causing a slightly different pupil diameter, which will affect value and color perception. Its something I've observed when relaxed, and staring at pale gray surfaces, like the ceiling of a room, or a pillowcase. The differences are subtle, but can be detected if one is looking for it. I'm sure there are a variety of factors that could contribute to this. Even the act of comparing by closing one eye is probably contributing to the effect. There's really no reason why the eyes should see EXACTLY the same color, even if that is the PLAN...
 
Thanks pals, this is something I've never noticed before, but while I was using the dioptre adjustment I was staring at a very white object.

Gijs, your suggested hypothesis may have merit, as I was doing this in the house and my one eye was nearer the window than the other. I shall investigate another day and see if this phenomena persists.
 
I've noticed this phenomena in my own eyes on some occasions.
There's really no reason why the eyes should see EXACTLY the same color, even if that is the PLAN...

Spot on, different acuity between left and right eye is quite common. That reflect a fairly coarse structural difference. Color perception is much more of a sensor phenomenon, so variation might be much wider still.
I wonder whether some people are color blind on one eye only. It does not seem implausible that it might be mostly unnoticed.
 
Jremmons, in this thread I refer to the present subject, and the matter being brought up a few years before that in this forum. From what follows in the thread, and what I remember now, it may have been Chosun Juan who first did so. I am afraid I have not been able to locate that original thread. Nor can I point out where in the linked thread, at what previous post, the matter comes up, if it does come up before I mention it, as it is a bit tedious to search back for it.
 
The brain's ability to perceive colours correctly (almost) regardless of the incident light is the result of an intricate auto-whitebalancing working with comparisons and adjustments.
If you watch a green circle for a while and then turn your eyes towards a white wall, you'll see a purple circle.
The brain is constantly fine-tuning the perceived colours by comparing how objects look with how they should look, and subsequently adjusting them.

Since the eyes (or rather the brain, which the eyes are a part of) can adapt so quickly and easily, I highly doubt that the difference in perceived colour bias between the right and the left eye is an error.
Until proved wrong, my strong belief is that this difference is a vital part of the reference firmware used for the auto-whitebalancing system.

I read somewhere that some owls have their ears at a slightly different height, so that they can estimate how deep down under the snow the prey is.
What initially seems to be a structural imperfection is the opposite, a mean to achieve functional perfection.

//L
 
I must admit when this topic was first raised on the forum I was a bit sceptical. As others have pointed out It's so easy to induce yourself into thinking there are differences that are not really there. I'd noticed one or two differences between my left and right eyes but not colour. However the physiology of the eye does vary between individuals and with age so I supposed the reports might be due to something like uneven pigmentation which would be increasingly likely with age. I did try a couple of online colour discrimination tests and sometimes one eye did better than the other but wasn't really convinced I could find a difference.

I have had a hunt around online and have found that differences in colour sensitivity between eyes have been reported in the scientific literature. One study on Finish students found a statistical difference between dominant and non-dominant eyes. I should point out that the standard deviations were large and therefore it wasn't common to everyone and mostly applied to red/green discrimination if I understood the paper correctly.

I didn't find an explaination why but it seems that there are other measurable differences between our dominant and non-dominant eyes. We are inclined to see things as larger, clearer and for longer with the dominant eye. I even found a claim that there is a detectable difference in sensitivity to polarised light. We are curious animals. ;)

David
 
Last edited:
Thanks Normjackson, for identifying the older threads, and pointing out the prior ref. above. Sorry Bruce, I somehow missed that! It is Sancho, then, who has first brought the matter up in this forum, as far as I know now.
 
Let me, once again, stress that while the eyes receive light, it's the brain we effectively see with.
If for sudden a major change occurs, like a bursting blood vessel in the anterior chamber, you will notice.
Slow changes like the development of cataract will pass unnoticed thanks to the brain's exquisite ability to adapt and adjust.
A single-sided cataract surgery will reveal the vast colour shift you learned to accept.

In the light (sic!) of this I'm certain it's not feasible to believe the brain wouldn't adjust the colour perception to be equal in both eyes if neded, and that the ostensible difference between the eyes is a construction happening in the brain.
As a side note, I discovered this phenomenon with my very own eyes aged seven.

//L
 
Last edited:
...A single-sided cataract surgery will reveal the vast colour shift you learned to accept...L

Amen! For two weeks after right eye surgery, I went around with 20\13 perfectly clear bright colorful vision with a 20\700 left eye that showed yellowed whites and dull, washed out colors! Never noticed the slow and steady transformation that the cataracts were doing to my vision over the previous 5-6 years. Once the left eye surgery matched the right, whites are brilliant and colors POP like they never did before, now in full Binocular Technicolor Vision! ;)

Ted
 
Whilst I've noticed readily apparent differences in colour temperature between one eye and the other in the past, as seen by alternately closing one eye only, then the other, I can't see it now.
I'd suspect asymmetric lighting, such as spending time sitting side on to a window.
 
Thanks for pointing this out! I checked this the day before yesterday and yes - my right eye perceives colours a little more vividly (reds seem to stand out more) than my left. I have no idea whether this was always so and it mightn't be a bad idea to note things like this down for the future. My right eye is the dominant eye.
 
Warning! This thread is more than 7 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Users who are viewing this thread

Back
Top