What color value is skin tone?

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Level 1

1 points

What color value is skin tone?

If I want to push skin tone in the Colour Board (Apple's rectangular version of the "colour wheel") in a colour adjustment, should I be pushing at 30 degrees?

The FCPX user manual says in "Vectorscope display options",

"Show/Hide Skin Tone Indicator: Shows or hides the diagonal line that represents the human skin tone chroma phase, which is between the yellow and red color bar targets."

It doesn't say if the skin tone indicator is exactly between yellow and red, i.e. pure orange, which would be 30 degrees, or just somewhere between red and yellow.

I found this in a Larry Jordan article,

"Regardless which race or ethnic group our actors are a part of, all of us have the same red blood under our skins. This line (skin tone indicator) represents the color of red blood under skin. In general, when you want to make skin tones look normal and believable, you want them within a couple of degrees of this line. Above the line leans ruddy, below the line leans sallow."

So, is the red blood under our skin pure orange, i.e. 30 degrees in the Colour Board, i.e. exactly mid way between red (zero degrees) and yellow (60 degrees), or is it some other value?

Final Cut Pro X

Posted on Jun 4, 2013 11:39 AM

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Answer 1

Tom Wolsky

Level 10

152,015 points

Jun 4, 2013 11:44 AM in response to wyljon

This is the flesh line in the vectorscope

Actually doesn't have anything to do with red blood. That's not what adds color to flesh.

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Answer 2

wyljon Author

Level 1

1 points

Jun 5, 2013 3:27 AM in response to Tom Wolsky

Does anyone out there know the answer? I've had a good look online, but cannot find the answer. The question again:

To push skin tone in the Colour Board, do I need to push at 30 degrees, i.e. pure orange, or is it some other value?

If you know the value, please let me know.

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Answer 3

Tom Wolsky

Level 10

152,015 points

Jun 5, 2013 3:39 AM in response to wyljon

I'm sorry, was I not clear you push the color value all the flesh line in the vectorscope. How much you need to adjust your color on the color board is determined by the original values. What you're trying to do is to place normally lot flesh on that line.

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Answer 4

wyljon Author

Level 1

1 points

Jun 5, 2013 4:22 AM in response to Tom Wolsky

Thank you Tom. I understand how to read and work the vectorscope in relation to the skin tone indicator. I referred to the vectorscope and skin tone indicator however only because their existance indicates that there is a definite value (measured in hue, which is measured in degrees) where human skin tone is found. My question is what is that value in degrees. I cannot find the answer either online or in the FCPX user manual. Is it 30 degrees, pure orange, or another value?

As an aside, hue in skin does appear to have something to do with red blood, specifically the haemoglobin in blood.

"Skin tones are based on hemoglobin and melanin. Hemoglobin controls hew, while melanin controls mostly brightness and saturation."

This quote is from http://www.curvemeister.com/forum/index.php?topic=57.0

Other places I've read that the hemaglobin is red and the melanin is yellow and that the hue value results from a mix of the two.

I'm not very interested in the sciene of it. I really am just looking for the hue value of skin in degrees, specifically that point where Apple have put their skin tone indicator, at a specific point between red (zero degrees) and yellow (60 degrees). What is that point? What is its value in degrees?

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Answer 5

Tom Wolsky

Level 10

152,015 points

Jun 5, 2013 4:58 AM in response to wyljon

The quote is a grotesque oversimplification. But whatever.

My protractor shows the flesh line at 30 degrees from vertical. Pure orange, not sure if that's a technical term, would be half half way between yellow and red, which on my protractor is about 45 degrees from vertical. Not sure what value these number have for you.

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Answer 6

wyljon Author

Level 1

1 points

Jun 5, 2013 8:57 AM in response to Tom Wolsky

Thanks for that. The reason I wanted to know this is because I want to experiment with the complementary colour grading technique of pushing skins tones in the highlights and pulling shadows in the opposite direction (into blue), as per many recent Hollywood blockbusters films.

Looking at the vectorscope wheel/circle, 'pure' red seems to start somewhat to the left of centre/vertical. The Colour Board in FCPX's Colour Correction section has pure red at 0 degrees. Therefore, taking your figure that the flesh line is at 30 degrees from vertical, I will subtract say 15 degrees to account for pure red not being at vertical in the vectorscope wheel/circle. That suggests that the skin tone indicator line if it appeared in the Colour Board would be at about 15 degrees, which is between red (zero degrees) and yellow (60 degrees), but much closer to red than to yellow. This finding supports some tests I've just done where I pushed orange on a white image and found that the flesh line was met when I pushed at 15 degrees in the Colour Board.

So, to answer my own question, skin tone (the skin tone or flesh indicator) lies at 15 degrees on the Colour Board.

When I did another test, not on white paper but on a sample skin image, the skin tone indicator in the vectorscope was met when I pushed the highlights at 20 degrees (I pushed them considerably).

When I then did the same test just mentioned but also pulled back the shadows and midtones, I had to adjust everything at 29 degrees before the flesh line was met.

Hope this is of help to someone. Feel free to comment. No doubt I may have missed something.

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Answer 7

Tom Wolsky

Level 10

152,015 points

Jun 5, 2013 9:50 AM in response to wyljon

To be honest I have no idea what degrees on a flat two-dimensional board means. Pushing highlights into white I get 16 "degrees."

When I did another test, not on white paper but on a sample skin image

That can be very dependent on the original image.

One problem is that FCP works in RGB so luminance values will change color values. If you push shadows and highlights both on pure white they will not be at the same "degree" value. The higher you push them the greater the divergence as much as five "degrees."

When I then did the same test just mentioned but also pulled back the shadows and midtones, I had to adjust everything at 29 degrees before the flesh line was met.

If this is the skin sample test, then you'll get different results based on the original image.

On white, an image with all colors in equal proportion, pushing and pulling highlights and shadows puts them almost on the same point 18 and 19 degrees or you can get the same result by pulling shadows to 184 (negavtive cyan-blue, which would be the opposite direction). Pushing shadows to flesh and pulling highlights, requires moving highlights to 196. Pushing mids will bend the gamma and will produce different results from pulling. Pushing mids will go to 22 degrees to add flesh, but pulling mids has to go to 201 (negative blue-cyan) to add flesh. It's not precise because the luma values will shift it around.

Basically the skin values won't be consistent for all flesh because of their luma values, and you'll have to move around based on the vectorscope and your eye rather than just numbers. Color grading is really more art than science.

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Answer 8

wyljon Author

Level 1

1 points

Jun 6, 2013 4:16 AM in response to Tom Wolsky

Many thanks for all your help. I suppose I am trying to arrive at really nice cinematic looking skin tones, but with my Canon 550d and very limited knowledge of setting up shots and film making, pushing skin tone and playing with the colour board alone will not get me those appealing skin tones. Attached are some interesting ones, but how to achieve them? I need to keep learning, and perhaps have a good lot of cash for gear ..

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Answer 9

Tom Wolsky

Level 10

152,015 points

Jun 6, 2013 7:15 AM in response to wyljon

First one isn't very good in my view. Poorly lit, different color temptures left to right, or maybe it was an artistic choice, either on the set or in post to make her warmer and him colder. Probably in post because the background is even. Hard to really tell with these small images, but I don't care for it. Probably masks on each character to treat them differently.

Second one has warmed mids, pushed to give that golden hour look. I like it.

Third one's the same, warm blacks and whites, sorry shadows and highlights. Don't like it so much. Bit too much push to it, making the overall look too warm and unnatural.

Fourth is classic Michael Bay, orange and teal, too orange flesh tones, orange center, blue backlight and background. You'll see it in almost every shot in his movies.

The fifth is quite neutral. A little warm in the highlights, colder in the midtones.

The last one is reduced saturation, slightly cold highlights, similar to the guy on the right in the first image, though not as extreme, pretty neutral like the image above, slightly more blue in the highlights, while the image above has more warmth in the highlights.

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Answer 10

Jun 6, 2013 8:07 AM in response to wyljon

wyljon wrote:

… I need to keep learning, …

you heared of this friendly fellow?

http://www.colorgradingcentral.com/final-cut-pro-x-color-grading-table-of-conten ts

he's offering tons of free tutorials to teach you the basics of grading.

plus, he needs a living, sells a FCPX package for 50$ which covers many of the looks you're mentioning.

keep a few things in mind:

• professionals have studied these techniques for years, no click-button-done-thingie 😉

• a worse recording doesn't get better by grading

• digging deeper, you will hear of 'flat profiles' etc - that reflects mostly for cinema-cams, not consumer toys like ours … even the best recording from your DSLR will not look like a Michael Bay film - ok, manage to hire Megan, and nobody is interested in your color profiles 😉

• talking of learning: we all heard of 'that movie was shot with an iPhone' - spend 2h on this Emmy-awarded docu

http://www.zacuto.com/the-great-camera-shootout-2011

don't miss pt II, The Revenge

http://www.zacuto.com/shootout-revenge-2012

.... in short: it's not the camera, nor the computer, it's the skills of the photographer USING LIGHT to 'paint'

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