Very useful CCT/tint shots!

clemence · 2018-05-20T13:49:52.000Z

I found a very good color wheel.

Printed the color wheel on a A4/4 plain paper. Nothing fancy, just office HP Deskjet printer. Stuck it on the wall and made the shots. WB set to 5600K. Then some editing to minimize brightness/contrast difference between shots without altering any color.

The result was surprisingly good. By simply doing this, I can see so many things within minutes. I’m not a color expert just like most of us here and this somewhat artsy tint shot compilation helps a lot when I need to decide which LED to use.

- Clemence

EDIT: I disabled my printer color profile. I used Adobe sRGB instead

Parametrek · 2018-05-20T14:45:53.000Z

You can also buy color wheels for like $5. These are usually preferred to DIY printed ones because they usually use pigments for each color instead of blending cyan/yellow/magenta.

Technically speaking 3 plain squares of cyan/yellow/magenta contain as much information about the light’s tint as a printed color wheel.

clemence · 2018-05-20T14:54:25.000Z

Parametrek:

You can also buy color wheels for like $5. These are usually preferred to DIY printed ones because they usually use pigments for each color instead of blending cyan/yellow/magenta.

Technically speaking 3 plain squares of cyan/yellow/magenta contain as much information about the light’s tint as a printed color wheel.

Correct, but those pictures cost me less than $0,02. Will buy a professional color wheel later.

- Clemence

Pavlo · 2018-05-20T15:02:50.000Z

Nice comparison Clemence. E21a in 5000k looks beautiful!

adam7027 · 2018-05-20T16:41:56.000Z

Nice comparison. It shows, that we still lack cold/extra cold white good CRI emitters (6500K to 12000K), because that is a difficult story.

I already think about ordering a quad of E21A 6500K, because Maukka measured it around 7100K, and that is the only one really cold white emitter with high CRI.

Two more headlamps for emitter swapping are already on their way to me.

The E21A 2000K looks so deep :sunglasses:

mattlward · 2018-05-20T17:17:57.000Z

I think this would be interesting if shot with white balance matching the emitter tint. I think it would bring out the visible advantage of the CRI of each. Our eyes tend to adjust white balance when looking at things and we do not see the solid orange of the warmer tint emitters.

jon_slider · 2018-05-20T19:26:45.000Z

clemence:

WB set to 5600K.

great pics!
I would like to see same with WB @ 4000k, 3000k, and 2000k

mattlward:

I think this would be interesting if shot with white balance matching the emitter tint.

agree
looking at a 2-3-4000k emitter, with White Balance set to 5600k is not my real world application of night time flashlight use. Also, when camping with no ambient light, I find 3000k very pleasant, while 5000k+ is overly blue. Same waking up in the dark, my brain finds 5000k+ too Cool.

All depends on the WB of my brain at the time. Example, my house lighting is 3000k incandescent. After 30 minutes in that environment, my brain sees 5600k as WAY too blue.

otoh, during the day, when my brain is adapted to Cool White Sunlight, even 4000k looks too orange.

So, my choice of CCT changes based on what White Balance my brain is adapted to.

whether a light looks Cool or Warm, depends on the White Balance of the operators brain at the time.

IF the operators brain is adapted to sunlight, then a CW light will seem white, and a NW light will seem warmer (yellowish).

otoh, IF the operators brain is adapted to darkness (takes 30 minutes in the dark), then the CW will seem blueish and the NW will not seem yellowish.

the following photos are from iPhone 8 with Automatic white balance. Notice how their color changes based on what they are being compared to. Remember the camera is changing its white balance in every shot. IF the photos were taken with a camera with a Manual white balance setting, then all the colors would stay the same. (and what those colors would be, would change based on which white balance Color Temperature was being used)

A light will look blueish if it is cooler than the white balance of the brain at that time. And a light will look yellowish if it is at a lower CCT than the brain is adapted to at that time.

clemence · 2018-05-21T06:03:59.000Z

EDITED: I now use different WB to change the RAW files. My software can’t correctly change the WB after the files converted to JPEG.

As requested (click for full size):

1. WB varied before RAW - JPEG conversion. Limited 6500K - 3000K because DxO can only change the WB down to 2700K.

2. WB varied after RAW - JPEG conversion (false results)
I used the circular center whites as the reference point

- Clemence

jon_slider · 2018-05-21T07:22:31.000Z

Thanks Clemence

At 3000k WB the 2000k is not too bad
at 5000k WB, or even at 4000k WB, the 2000k is not too good

seems it is a better match when the flashlight and the White Balance are within 1000K of each other

AlexGT · 2018-05-20T23:50:12.000Z

Thank you for the information, What specific settings do you use on your camera to capture the tints correctly?

Thanks
AlexGT

clemence · 2018-05-21T01:02:54.000Z

AlexGT:

Thank you for the information, What specific settings do you use on your camera to capture the tints correctly?

Thanks
AlexGT

I just trust my camera, that’s all. It’s slightly over saturated than the real life but that’s to be expected.

Camera: Olympus O-MD EM5
Lens: M. Zuiko 12-50mm, f 3,5 - 6,3

50mm f6,3
All Manual
ISO 200
Average metering
IS 1
RAW input (This also means any color related settings in the camera don’t affect the output)

RAW - JPEG conversion software: DxO Optics Pro 10

Standard geometry correction module
No color alterations

Editing software: ACDSee Ultimate 8

Contact sheet
Contrast/brightness adjustment
Vignetting
Captioning

- Clemence

AlexGT · 2018-05-21T01:32:20.000Z

Thanks

clemence · 2018-05-21T06:04:26.000Z

Multi WB post edited: Very useful CCT/tint shots! - #8 by clemence

jon_slider · 2018-05-21T07:30:49.000Z

clemence:

Multi WB post edited: Very useful CCT/tint shots! - #8 by clemence

thanks, updated post 9 with your new WB images

If Im acclimated to 3000k Incandescent, then ± 1000k is pleasing, ie, 4000k or 2000k
If otoh, Im acclimated to 5000k White Balance, then ± 1000k is still pleasing, ie, 6000k or 4000k
note that in WB of both 3000 and 5000k, that the 4000k is within +–1000k

nsl18 · 2018-05-21T13:39:16.000Z

This is an kruithof curve function. I have noticed that 4000k lights was bluish at far zone border

eas · 2018-05-21T23:54:41.000Z

clemence:

Correct, but those pictures cost me less than $0,02.

You sure about that? Large patches of color ink and/or color toner aren’t cheap. Less than $5/page though

clemence · 2018-05-22T01:15:05.000Z

eas:

clemence:

Correct, but those pictures cost me less than $0,02.

You sure about that? Large patches of color ink and/or color toner aren’t cheap. Less than $5/page though

I refilled my ink cartridge. The cost for large black ink is ~USD7/refill and the color (-RGB-RYB) ~USD10. And I printed on used 80gr/m^2 A4/4 paper (105mm x 150mm). There is a famous ink refill center here called VENETA System. It sells refurbished/recycle ink cartridge and also ink refilling using bio-degradable inks.

- Clemence

DavidEF · 2018-05-22T00:55:17.000Z

This is an interesting experiment. I’d like to see if the “real” color wheel works better for this kind of ‘discovery’ experiment, as has been mentioned. Especially interested in that because refill inks, in my experience, are usually lower quality than OEM. So, the difference might be even bigger than if Clemence had used OEM inks, which are already not ideal for this.

clemence · 2018-05-22T01:19:15.000Z

DavidEF:

This is an interesting experiment. I’d like to see if the “real” color wheel works better for this kind of ‘discovery’ experiment, as has been mentioned. Especially interested in that because refill inks, in my experience, are usually lower quality than OEM. So, the difference might be even bigger than if Clemence had used OEM inks, which are already not ideal for this.

budget living has been infiltrated my life.
FYI, the refill ink quality is almost as good as the OEM at 1/3 the price. I don’t expect significant differences by trying OEM ink cartridges. Better start browsing for real color wheel.

- Clemence

DavidEF · 2018-05-22T01:28:02.000Z

clemence:

DavidEF:

This is an interesting experiment. I’d like to see if the “real” color wheel works better for this kind of ‘discovery’ experiment, as has been mentioned. Especially interested in that because refill inks, in my experience, are usually lower quality than OEM. So, the difference might be even bigger than if Clemence had used OEM inks, which are already not ideal for this.

budget living has been infiltrated my life.
FYI, the refill ink quality is almost as good as the OEM at 1/3 the price. I don’t expect significant differences by trying OEM ink cartridges. Better start browsing for real color wheel.

- Clemence

Yeah, I wasn’t trying to suggest you should switch back. For most non-color-critical printing, it is definitely worth refilling for the price difference. I was just saying for something like this, I’d expect a “real” color wheel to be a huge upgrade.