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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

#51

Post by klabb3 »

fmajid wrote: post #44
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…

Not to mention the Color Rendering Index (CRI) metric Ra does not weigh the R9 (deep red) so many forms of lighting don't try to render it correctly to save costs.

This is truly an (accidental?) setback of color reproduction as it has progressed over time. For LED lights R9 is also crucial for skin tones which makes it so bad to just leave that out. Now, the mass produced LEDs are even optimized for CRI at all are virtually all excluding R9, which may be one of the main quality issues that many people perceive with LEDs vs eg incandescent. There’s of course more to it but R9 probably has a disproportionate effect for being a ”minor detail”.

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

#52

Post by dkeners »

This reminds me of a video [1] going over the use of structural color photography, where theoretically what you see in real life is what you get in your final image. It cover some of the same topics, but goes more in depth about the process of structural color and some animal examples, like the butterfly mentioned in the article. If you have an interest in chemistry or film photography it is a great watch! This process was also, to my knowledge, the stepping stone for holograms, which we can now see structural colors everyday on IDs and licenses.

[1] (18 minutes) https://youtu.be/-DyrBDsKA5s

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

#53

Post by carlosjobim »

psd1 wrote: post #24
frotaur wrote: post #17

Its unclear to me why the color space is 2-dimensional. Why wouldn't it be a 3-dimensional space, indexed by how much each of the 3-cones is activated ? Not clear to me from the article!

It is, inasmuch as we have 3 types of cone, which is an inherent orthogonality. It is also not, inasmuch as each cone is a wavelength in the same spectrum. Either way, you can project a volume onto a plane, which is great for communicating visual data on paper or screen. The interesting question is "why that arc in particular"; my ignorance will shine through if I speculate. I assume that the projection encodes somet…

It is 3 dimensional, because in our perception we see the third dimension of magentas and purples, which do not exist in physical reality on the spectrum.

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

#54

Post by klabb3 »

adrian_b wrote: post #49
red75prime wrote: post #37

Earlier quoted context omitted.

> the relation between those areas would be opposite in a uniform color space. If I understand correctly fig. 3 in [1] should be perceptually uniform. The bluegreens missing from sRGB, but present in BT.2020 comprise a sizeable chunk comparable to redyellows. [1] https://www.researchgate.net/publication/345252499_Evaluatin...

Indeed, "Figure 3" from that article should be a realistic depiction of the differences between sRGB, Display P3 and BT.2020. It is true that both the red and green primary colors of sRGB are bad (because they correspond with obsolete CRT phosphors that have not been used for decades), but in practice the defects of the green primary color are much less important, because the objects with saturated green colors are m…

> Only very rarely I have seen examples with obvious differences between monitors when showing green objects, e.g. some documentaries with certain vividly colored animals, like some insects, birds, frogs or lizards.

According to the article you get purified greens from transmittance through foliage, ie backlight in eg a maple forest. This makes me suspect that it may be more important than just exotic animals, and maybe we are more sensitive to ”greens” than we think? For instance, a lot of my photography of trees/forests tend to feel much more ”green brown mess” and loses structure when going from reality to screen. (Another explanation is that my photos are bad, but I like that one less)

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

#55

Post by carlosjobim »

thinkingemote wrote: post #5

Can these colours be replicated or captured using ink, paint or traditional film photography?

Many colours outside of the electric screen spectrum can be made with ink or paint. You probably have a bunch of objects in your own house with colours that can't be shown as full on your screen.

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

#56

Post by adrian_b »

klabb3 wrote: post #54
adrian_b wrote: post #49

Earlier quoted context omitted.

Indeed, "Figure 3" from that article should be a realistic depiction of the differences between sRGB, Display P3 and BT.2020. It is true that both the red and green primary colors of sRGB are bad (because they correspond with obsolete CRT phosphors that have not been used for decades), but in practice the defects of the green primary color are much less important, because the objects with saturated green colors are m…

> Only very rarely I have seen examples with obvious differences between monitors when showing green objects, e.g. some documentaries with certain vividly colored animals, like some insects, birds, frogs or lizards. According to the article you get purified greens from transmittance through foliage, ie backlight in eg a maple forest. This makes me suspect that it may be more important than just exotic animals, and ma…

> According to the article you get purified greens from transmittance through foliage, ie backlight in eg a maple forest.

This sounds plausible. I think that in general for content that you record yourself, where you would record whatever is interesting, e.g. the more unusual things, especially outdoors, it is more likely for all the parts of the color space to be important.

My point was that for the content most frequently watched on a monitor, like commercial movies, it is much more likely that the main effect of using the obsolete sRGB color space is to see a lot of objects whose color is in the orange/red/purple area and which appear to have washed-out colors.

In almost any commercial movie, if I switch at almost any point between a Rec. 709 copy on an sRGB monitor and a Rec. 2020 copy on a Display P3 monitor I immediately notice some reddish objects that have become more vivid, looking like in real life, while on sRGB they look abnormally dull.

Until a dozen of years ago, I had used for many years sRGB monitors and I was content with them, but immediately after I used for the first time a Display P3 monitor I could no longer enjoy sRGB photographs or movies, because now their limitations had become obvious.

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

#58

Post by lukewarm707 »

interesting, nicely written article. if you want to replicate the colors, you can use wider gamut end to end:

- use raw format on the camera

- edit raw eg pro photo rgb

- send this to a wide gamut printer with a large set of inks to view the image

the printer would replicate the color outside the srgb space

there are such inks as cyan, light cyan, orange

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

#60

Post by functionmouse »

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.

it'll be awesome, once
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