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Where to Find the Colors Your Screen Can't Show You

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Re: Where to Find the Colors Your Screen Can't Show You

#91

Post by zahlman »

mceachen wrote: post #86
whiw wrote: post #79

If we had a display with n (n>3) pixel colours, say (red, green, cyan, blue) for example, we could display more of the colour space. Shopping list: 4 colour channel display, 4 channel GPU, 4 channel software. Why isn't this a thing already?

More than 3 channel displays have been attempted by several companies, but I suspect they fail due to: 1) trying to convince content makers to use new custom high-gamut hardware to capture the new spot colors 2) you'd need a full video content production pipeline that can render to that color space 3) finding enough people to care enough to pay the (substantial) premium for niche production numbers. 4) Most content j…

5) You'd need image formats that record those channels, and that in turn would cause problems for raw bitmaps with alpha (they either get twice as big or the pixels are no longer aligned).

Re: Where to Find the Colors Your Screen Can't Show You

#92

Post by jakzurr »

TheAceOfHearts wrote: post #8

I took up acrylics painting a few years back and I've been surprised by how much is lost in photos and videos. The two colors with which I've noticed this the most are ultramarine blue and prussian blue. I don't think it's just the color though, part of it comes down to how light is reflected off the painting and where you're standing, as well as the texture and the brush strokes. I have a few paintings hanging in my…

Thanks mentioning acrylics. Now I'm wondering if new technology will eventually improve our printing to allow better colors in news media, and even in prints in art exhibits?

Does anyone have any comments on the future of printed media?

Re: Where to Find the Colors Your Screen Can't Show You

#93

Post by jfengel »

adrian_b wrote: post #21

While it is true that some saturated blue-green colors will never be reproducible with only 3 primary colors, the CIE 1931 chromaticity diagram used in TFA overemphasizes their importance, because human vision cannot distinguish many colors in that area of the diagram. In reality, the greatest defect of the sRGB color space, which is still too frequently the default color space, is that it is not able to reproduce ma…

As I understand it, JPEG cuts out a lot of detail in the blue range, because we don't see it as well. Is that due to the same thing as you're saying here?

Re: Where to Find the Colors Your Screen Can't Show You

#94

Post by thadk »

Somewhat related, but TIL the macOS Screenshot.app utility (and the system wide keyboard shortcuts) in Sonoma got HDR capability to help re-convey just a bit more fidelity. Even in PNG, it keeps the display profile, just not HDR.

Open Utilities->Screenshot.app Options->Capture/Capture Format->HEIC. Note, it changes the system screenshot default away from PNG too.

Re: Where to Find the Colors Your Screen Can't Show You

#95

Post by Dwedit »

jfengel wrote: post #93
adrian_b wrote: post #21

While it is true that some saturated blue-green colors will never be reproducible with only 3 primary colors, the CIE 1931 chromaticity diagram used in TFA overemphasizes their importance, because human vision cannot distinguish many colors in that area of the diagram. In reality, the greatest defect of the sRGB color space, which is still too frequently the default color space, is that it is not able to reproduce ma…

As I understand it, JPEG cuts out a lot of detail in the blue range, because we don't see it as well. Is that due to the same thing as you're saying here?

That has more to do with RGB -> YCbCr conversion, and how much blue contributes to Y (brightness). If you quantize YCbCr down to 8-bit range (0-255 range), you'll get RGB colors that can't survive a round trip back between RGB and YCbCr, but I don't think blue is particularly worse there.

JPEG is a different thing, first it does RGB -> YCbCr conversion, then it splits the image into blocks. Wikipedia article shows a good diagram of the 64 possible DCT blocks. Each image block becomes a linear combination of the DCT blocks. You did that for the Luma channel, then you do the same thing for the Chroma channels. It's even common to reduce the resolution of the chroma channels (chroma subsampling).

Then JPEG means that you are deleting information that is less popular after you've made your blocks. Often throwing out more information in the chroma channels than the luma channel. You're left with ringing (high frequency noise to fill the block), and blocking (differences between edges of adjacent blocks). Better compression codecs have ways of mitigating blocking and ringing.

Re: Where to Find the Colors Your Screen Can't Show You

#96

Post by mrgaro »

Great article! After reading I started to think there must be some purchable items which would demonstrate colours outside P3 colorspace. It would be cool to hold one on your hand and experience how a photo of it just cannot do justice.

Anybody know any links to webshops for such items?

Re: Where to Find the Colors Your Screen Can't Show You

#97

Post by TeMPOraL »

tomaskafka wrote: post #4
lefra wrote: post #3

Really nice article, I'll look closer to green lights next time I see one. The most striking experience I had was working with a blue laser (430nm). The best way I found to describe its color is that it was screaming "blue" at me. Since then, I'm always disappointed when looking at a screen displaying #0000FF.

Sounds like we need the next VR glasses to shine colorful lasers into our eyes instead of screens.

If we could get that to work, then we'd be much closer to VR without a headset - a device able to paint arbitrary images directly onto users' retinas could be stationary and handle multiple users - giving us a holodeck, just without the tactile parts.

Re: Where to Find the Colors Your Screen Can't Show You

#99

Post by m3047 »

jakzurr wrote: post #92
TheAceOfHearts wrote: post #8

I took up acrylics painting a few years back and I've been surprised by how much is lost in photos and videos. The two colors with which I've noticed this the most are ultramarine blue and prussian blue. I don't think it's just the color though, part of it comes down to how light is reflected off the painting and where you're standing, as well as the texture and the brush strokes. I have a few paintings hanging in my…

Thanks mentioning acrylics. Now I'm wondering if new technology will eventually improve our printing to allow better colors in news media, and even in prints in art exhibits? Does anyone have any comments on the future of printed media?

The way this is done (has been done) is printing with custom colors. Standard printing is done with CMYK (three colors and black). Purportedly high-end printers (I don't care if the printer is gold plated and diamond studded, if the driver / host-based preprocessor was written in 1999 using Visual BASIC then the printer is sh*t) have had an extra blue, or an extra red, for years.

In the back of my mind, I find it oddly surprising that we have 3D printers but I haven't seen a printer where you can mix your own pigments and print with them.

Many years ago I knew someone in Seattle who made microprints with burnished copper plates, some of them with a dozen different colors. He designed a couple of commemorative postage stamp-like objects, and that somehow got him hired by an eastern european country as an anti-counterfeiting advisor and then he disappeared.

Re: Where to Find the Colors Your Screen Can't Show You

#100

Post by m3047 »

hyttioaoa wrote: post #98

My two most favorite and most seldomly seen colors are near uv. One of them is a blue sky at an altitude of over 3000m. The other was a powerful deep blue laser in a microscopy lab, just on the end of the visible spectrum

One of the things which is unaccounted for in both printing and lighting is florescence.
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