Tint Perception depends on what it is being compared to

LED Flashlights – General Info
1

tint perception is relative to other light sources

in the case of me using a single light, it changes tint when I shine it on a wall during daylight (5600k w duv 0.0033), and again when I shine it on a wall when I have incandescent lights on in the evening (3000k w duv 0.0000)

tint is absolute in as much as a duv number can be named
but what I see, depends on what else Im referencing

some photo examples
watch how a light with pink tint when compared to one with a higher duv, changes to green tint, when compared to a light with lower duv

the light on the right stays the same in the next two images:
first the LH351d looks pink:

then it looks greenish yellow:

another example
the light on the right stays the same again, in the next two images:
first the E21a 4500k looks pink:

then it looks Not pink:

for these reasons, I am not a fan of single beamshots
I prefer to see an LED I own, being compared to an LED Im curious about

that kind of comparison informs me whether the LED I have not tried is of a higher or lower duv, than the light I own.

the important distinction is the relative difference in duv. even if both LEDs have tint below the BBL the one further away will look pink and the one closer to the BBL will look relatively green.

It has taken me 5 years to reach this understanding. If you agree, disagree, or simply do not understand… give it some time to sink in… and try some of your own comparisons :slight_smile:

2

I totally agree with the point being made (tint is relative to a large degree). This can easily be demonstrated while playing with multiple lights of varying tints.
However, I am not sure those pics are the best to illustrate it, as it appears as though the white balance (and exposure) is not fixed for all. :beer:

3

This happens because cameras usually have auto white balance on by default.
If you turn that off then no the tint will not change.

4

thanks,

the concept I think is solid, and the images clearly illustrate a vast shift in tint
the equipment is very basic… iPhone 8 w auto white balance

totally agree the images could be improved
I invite anyone with the technical capabilities to improve on the examples

5

Exactly.

6

my eyes see a tint change similar to the photos I posted, when comparing two beams side by side, with auto white balance

I have learned you are correct that if I set white balance to a fixed value, the tint wont change, and that is not useful when shooting two beams in the same photo, because it is not what my eyes see.

I do agree that a fixed white balanced would be required if shooting one beam per photo… I dont shoot single beam photos. I always include more than one beam in the same image, precisely to show the relative tint between multiple beams.

7

I have set mine to off before and I still get pics with slightly different shades.
Maybe its just my phone camera and the results would be much better with a professional camera.

8

I think you’re right jon-slider.

I like a nice warm colour but specific tints and colour renditions are beyond what I care to take interest in

9

Depending on you having good… Eyesight.
Age comes into it too. as well as distances.

Long distance. Ie actually seing a thing. Static or moving.
6500/7500 is better for perception and movement.

Close up. “I”prefer 219b or c to give my OLD eyes a definition between items.
ALl my torches apart from one. 600lum, and less.
I run Nichia in them.
1000lum and above. I prefer and mainly use Cree and Philips.
6000 up

My eyes have also changed perseption. Betweem 75yrs and now (78)
And both are a lot less perceptive than when 60 yrs.
Main difference being strength of definition in lenses in glasses. Chuckle.
IE. Older = Blinder. ——- Tip. DON’T get old. Only oldER……

But you do change as you get into older yrs. 35up.

10

I believe there are a couple (free) camera apps you can download/use that allow for manual WB adjustment.
Might be worth checking out, if so inclined.

:+1:

Side note: If you ever want to sell/trade one of those V10R-Ti’s, let me know! :sunglasses:

11

Here is an example of two lights with very different tints (one very green, one very pink) compared to the same light (SC64w HI). The camera’s white balance has been locked at 4500K and tint is locked at zero. The SC64w HI’s tint appears identical in both images. Exposure is slightly different due to trying to match the two lights, but tint remains the same.

You are correct, your brain will adjust for ambient light. That’s why 2700K incandescent light bulbs appear white at night but very yellow during the day.


12

agree, thanks for the education

some requests, if possible

  1. shoot against white printer paper, so I can see the paper is the same in both pics
  2. set white balance to 5500k (D55 daylight white)
  3. set duv to 0.0033 (daylight D55 tint)

to my brain, when I do what you just did, the light on the right does not stay the same color, it changes, as in my photos…

so it appears that my photos more closely resemble what my brain sees, than what your camera shows…

do you agree that your zebra changes color, to your eyes, when compared to each of the two lights on the left? and therefore your pic does not represent what your eyes see?

thanks for your pics and effort to help w the white balanced images… I think that is unproductive, but appreciate your time
…

Here is my guess as to why your images dont change the tint of the zebra
your photos are comparing to a 3rd source, your white balance adjustment

whereas my photos are comparing the 2 lights in each photo, to each other… thereby capturing Relative tint, that more closely resembles what my brain does

13

It’s difficult to explain how white balance works. There isn’t really any such thing as absolutely white light, it always depends on white balance. Your brain adjusts for this on its own which is why you perceive light in the environment you happen to be in at any given time as white.

In my photos, the color isn’t really being “compared” to the white balance setting, the white balance setting determines what is white. When you manually set white balance, you are telling your camera what is white. So, in your photos with auto white balance turned on, you might be getting a similar effect to what you see with your eyes but the comparison is inaccurate because the white balance has shifted.

The reason auto white balance isn’t a good idea for comparing lights is because it can make even a pinkish light appear very green if you put it next to an even pinker light. It will always be relative. Locking white balance and tint will give you an absolute reference point. If you know the reference point, you can make a good comparison.

If I let my brain adjust and compare two lights side by side, yes, the tint will appear different. This is true for anyone. It happens all the time but you don’t notice it because your brain is very good at tricking you. It’s all about perception.

14

I believe that is correct, and for my purposes most useful

your images with preset white balance does not match what my brain sees when comparing two lights

for single beam photos, it probably would make sense to use a preset white balance
but
not when Im comparing two beams side by side

the auto white photos I posted, do a better job of showing what my eyes see, than the white balanced photos you posted. Thanks for taking the time to show me I dont need to buy a camera app, as long as Im not shooting single beams…

15

Whilst I agree with you for the most part Jon I think it is important to note the purposes of correcting white balance is for the benefit of those us who are viewing a given picture on a pc/mobile. In your situation you have given a variety of side by side comparisons which can help the viewer understand the colour. If a single pic is posted or multiple pics in the same lighting then that can deceive the viewer (e.g. as noted above one pink tint against an even pinker one). So a white balanced picture gives the viewer a standard point with which to gauge the colour. Of course, in real life the brain will make adjustments to the colour according to ambient or other lights…. but nobody will have the same ambient light and perception so it’s going to be different anyway. The only way to try and standardise the colour for everyone’s benefit is by using white balance.

16

I agree that a fixed, consistent white balance is important when shooting single beams.

otoh, I am learning that a fixed consistent white balance does not represent what my eyes see, when looking at two beams side by side.

If I set daylight white balance when shooting two beams in a single image, you would not get to see the relative tint that my photos show, and that my eyes see.

Try this at home…

grab a couple of lights, and shine them on a piece of printer paper, like I did
I think you will quickly find that our eyes do not use daylight white balance when comparing two beams side by side in the same image.

It does not even matter what the ambient light CCT is… our brain compares two beams side by side, and the relative tint changes based on which two lights are being compared, as in my photos.

Our brain does not use daylight white balance, when comparing two beams side by side, simultaneously. That is why I never post single beam shots… they frustrate me no end, cause the look nothing like what my eyes see when comparing two beams side by side…

17

So from what i’m understanding you are saying side by side tint shots are a poor way of capturing the tint of a given light

18

no and yes :slight_smile:
I think there are two separate goals and strategies that are being confounded…

I often compare lights to each other, and observe that the tints look different, depending what lights Im comparing. As in my photos. That is the reason I titled the thread
Tint Perception depends on what it is being compared to

no because

  1. my eyes interpret the tint relationship to each other of two beams side by side, similarly to what my auto white balance photos demonstrate

yes because
2. how a camera represents the tint of two beams, to a specific (preferably D55 daylight) white balance, is NOT going to show relative tint between the two beams. It shows relative tint to the selected white balance instead.

with scenario 1, the photo shows what my eyes see when looking at two beams side by side

with scenario 2, the photo only shows the beams relationship to the selected white balance. This is useful when photographing only one beam per photo.

both strategies have their pros and cons… one attempts to represent what the brain sees when comparing two beams to each other… the other attempts to represent what the camera sees, when comparing beams to a standard white balance reference.

…

now to extrapolate

when I shine a single beam on a white piece of paper at night (incandescent brain white balance), the tint looks very different, than when I shine the same light on a white piece of paper during the day (daylight brain balance)

I think this goes to help explain why I know my sw45k has pink tint (when I compare it to daylight), while I can honestly say it looks very white, even too blue at times, and I dont see the pink (when I compare to incandescent)

and from there
people that say sw45 is Too Pink, are probably white balanced to daylight, while I mostly use my lights, when Im white balanced to incandescent… (so I dont mind the pink during the day, cause I like the tint at night…)

similarly people who dont see the green tint that is so obvious to me in a 219c, are probably using the light when their brain is daylight white balanced (daylight has greener tint than incandescent).

19

Aah, perception of different tints side by side. So the method of comparison makes all the difference.

Side by side = auto white is better

Separate beam shots = fixed white balance is better

I think that’s what you’re trying to get at :slight_smile:

20

yes, and

when i look at a single beam during the day, it “looks” a different color than at night (two different white balances)

thanks for helping me make sense