Question about color shift in shadow area
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    Question about color shift in shadow area

    I have some questions regarding the colors in shadow areas in cases where I'm not sure if I have understood it in the right way.

    Therefore I consider three lighting conditions and I imagine a sphere in skin color:

    1) outside, afternoon situation: so I would model 1 white direct sunlight, 1 blue diffuse skylight and bounce light depending on the environement:
    so I would paint a skin color with a shift in color hue towards blue on the colorwheel (so r,g component is going down faster than blue) till the shadwo terminator. In shadow area I would paint skin color with even more blue shift and add bounce light colors of the environments (same for cast shadows)
    So far correct?

    2) artificial lighting: one white light from behind, one red light from behind:
    so I would paint normal skin color: now question: does the color shift towards blue or towards red in formshadow till terminator?? I would say the basic skin color should now shift towards red, with a total shift towards red in the 'shadow area' regarding the white light source?

    3) room with white or grey walls, no window, one white light source: question: is there a color shift or does the value in shadow areas just drop down and the hue stays exactly the same??

    4) does the material affect color shifts or only the various lightsources? I think of light scattering in skin (ears back light for example), so I assume there is a shift towards red (beacause the blood and muscular structure??) regarding a white light source. What about different colored light sources and material interaction?

    It would be totally cool if someone could en'light'en me ?

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    To me the purpose of colour theory is to help answer all of the questions that come into your mind when working from life ... not to save you the trouble of looking!

    I suggest that you begin by investigating these questions yourself, one by one, and from actual setups, and then ask again if you see something that you don't understand.

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    Yeah, that makes sense. I try to do this everyday though...

    Maybe I should question in another concrete way (because I couldn't figure this one out yet): so i noticed in countless photographs and paintings there is a slight color shift regarding skin color towards blue in form shadows.
    What would be the explanation: is it because there was always a diffuse blue light setting in these scenes? Would there be no color shift if there where no diffuse blue light just white light source and no bounce light?

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    Briggsy is absolutely right on this; go outside and look and observe and take notes. Observe under different conditions; sunlight, clouded days etc. and see if your theory holds true. Look at the source, not others interpretations in photos and paintings. You can never know if those images were processed to create some effect or if there is some limitation with the camera or user.

    Last edited by dpaint; March 30th, 2012 at 01:14 PM.
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    In his defense the more you know the more you can see. Then of course the more you see the more you end up learning and the more you know again. But that doesn't mean you shouldn't try to learn and know more outside of drawing.


    But..... I haven't even done many color studies overall and I learned more from drawing a bowl on my desk in sunlight than I did reading about it

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    Quote Originally Posted by dpaint View Post
    Briggsy is absolutely right on this; go outside and look and observe and take notes. Observe under different conditions; sunlight, clouded days etc. and see if your theory holds true. Look at the source, not others interpretations in photos and paintings. You can never know if those images were processed to create some effect or if there is some limitation with the camera or user.
    You're both right. I have done countless observation and I will continue on this. Nevertheless, I don't think its wrong to also take a look at paintings or photographs to examine the real rgb colors and watch the changes in value on the color wheel...

    But for me, the thing is: I learn from observation how it is, but not 100% why it is espacially this way...
    there might be more than one possible explanation for a noob.

    So I think my question in the last post is more an yes or no question and it would be kind if someone might come up with an answer to give me some certancy about my thoughts.

    Last edited by LaLaLaLa2; March 30th, 2012 at 02:05 PM.
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    Quote Originally Posted by LaLaLaLa2 View Post
    But for me, the thing is: I learn from observation how it is, but not 100% why it is espacially this way...
    there might be more than one possible explanation for a noob.

    So I think my question in the last post is more an yes or no question and it would be kind if someone might come up with an answer to give me some certancy about my thoughts.
    Everyone beat me to it ('cause I get up late).

    Then the answer to your yes or no question is....no. You're looking for one formula to explain an infinite set of circumstances. So basically your question is in error.

    You're also trying to understand something to a level that just frankly doesn't matter...and doing so from photos, or photos of paintings is misleading in the extreme.
    [Edit: I should clarify why it doesn't matter...as an artist you observe, simplify, interpret and make the statement you want to make. Artists take tremendous liberties with interpretation to make the statement they want to make...they are trying to create a cohesive image not replicate some scientifically accurate theory. Hope that clarifies what I meant by it doesn't matter.]

    It also sounds like you're doing it digitally by sampling rgb percentages from paintings. When you say you look at paintings to try to understand how an artists has handled value and chroma in shadows I assume you mean by going to galleries and museums to study these things. If you're not then it is meaningless.

    Learn to observe, directly from life...then interpret as you see fit.

    Last edited by JeffX99; March 30th, 2012 at 03:11 PM.
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    Slow down, be patient, put in the actual work. You're getting ahead of yourself, again.


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    Quote Originally Posted by Elwell View Post
    Slow down, be patient, put in the actual work. You're getting ahead of yourself, again.
    Yeah sorry for that, I was new to this forum and new to painting in general. I've learnt a lot since then, so I excuse for this question...

    But back to topic:
    I took a photograph as too see in the attached image: there was one white light source (monitor) and I guess some orange/brown reflected light from the table. So you can see a decent change in hue in the photograph and I can see it with my own eyes, too. But reading a lot of light tutorial regarding the value sphere the hue is mostly kept constant (e.g. http://www.huevaluechroma.com/pics/10-1.png). So I painted a part of my 'Burt's bees' by myself using hue change and no hue change (I've injured my hand so it's turned out a litte akward). But obviously, there is a difference. And I search a logical explanation for myself and try
    to understand. That's all. I don't want to annoy you guys.

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    Here is your answer
    Everything that has light falling on it becomes a source of light itself. So, anything you can see that has light falling on it in a scene has the potential to affect other things in the scene, including their shadows, depending on their spacial placement and orientation to each other.

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    Arrrggghhhh...."and then there was the gnashing of teeth". It's good to try to understand these things...but you're trying to understand it scientifically and as if one set of rules applies to every situation. Carefully read what has been written...the answer has been very clearly communicated.

    Don't put theory before observation.

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    Seems like everyone has run out of patience for answering Painting 101 questions.

    As other people said, you should do more studies until things become natural to you. Start with black and white studies to simplify things until you have a good handle on value (brightness), and move on to color studies after that. You'll probably also have an easier time if you set up your still life studies in a controlled way. You should also try the techniques in this thread.

    You may find this useful as well: http://itchstudios.com/psg/art_tut.htm

    I do some tips that may help your understanding of things:
    - Visible light can be split into three primary hues (red, green, blue)
    - When the primaries are mixed together evenly, they produce a neutral (gray/white)
    - All objects absorb and reflect light to some extent
    - Objects that absorb all or almost all light appear black
    - Objects that reflect all or almost all light (diffusely) appear white.
    - A red object absorbs all visible wavelengths except for red, which is reflected.
    - When light hits an object, the light that is reflected lands on and brightens other objects, essentially making the object a light source. (eg. the moon at night provides light by reflecting sunlight)
    - Objects can only reflect wavelengths of light that hit their surface - a pure red object in a room lit with a pure green light will appear black because there no red contained in pure green light.
    - Skylight and bounced light affect both shadow AND lit areas, not just shadow areas
    - While sunlight is yellowish and skylight is bluish (under "normal" conditions), either one can appear white depending on what kind of "color correction" you have in mind while painting. You can choose to paint things as you see them, as a camera would see them, or how Michael Bay sees them (orange and teal).

    (someone please smack me if I got anything wrong here)

    Last edited by SmallPoly; March 30th, 2012 at 08:16 PM.
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    Quote Originally Posted by SmallPoly View Post
    Seems like everyone has run out of patience for answering Painting 101 questions.
    It's more of a lack of patience when the question is answered in a variety of ways...but the person doesn't want to hear that answer...or give it the time and effort required for understanding.

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    Quote Originally Posted by SmallPoly View Post
    ....
    Thank you so much for your post. I've already visit and read the links you posted, they were a great help. So unfortunately, you told me nothing new.

    @JeffX99 I understand your point, but spent countless hours reading books/tutorials on realistic light. But somehow, for me it is hard to apply all my knowledge about colour to painting digitally with rgb/hsv/lab what ever... and the thing that bugs most me is the shift in hue, so I asked. There could have been a total simple answer i just couldnt came up with... but as it seems there isnt...

    So with regard to the above example: my explanation would be that the brownish/orange affects the object im holding in my hand creating a change in hue. Which brings to my next question (which I originally meant by 3) in my first post): If there where no bounce light from other objects, just one object, one light source and black walls: I would say in this case there should not be a change in hue. Does this sound right?

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    Quote Originally Posted by LaLaLaLa2 View Post
    Thank you so much for your post. I've already visit and read the links you posted, they were a great help. So unfortunately, you told me nothing new.

    @JeffX99 I understand your point, but spent countless hours reading books/tutorials on realistic light. But somehow, for me it is hard to apply all my knowledge about colour to painting digitally with rgb/hsv/lab what ever... and the thing that bugs most me is the shift in hue, so I asked. There could have been a total simple answer i just couldnt came up with... but as it seems there isnt...

    So with regard to the above example: my explanation would be that the brownish/orange affects the object im holding in my hand creating a change in hue. Which brings to my next question (which I originally meant by 3) in my first post): If there where no bounce light from other objects, just one object, one light source and black walls: I would say in this case there should not be a change in hue. Does this sound right?
    Uhm...sure, I guess? I've never been in a black room with only one object. Are you going to be illustrating a bunch of that kind of thing? And again...

    So yeah...to your point about spending countless hours reading and wrapping your head around tutorials. Those hours would be far better spent looking at things and trying to paint them.

    Asking questions is great...we've all been there and we all continue to ask questions...but, it is important to listen to the answers and try to understand how they apply.

    So, long story short...it seems to me like you're going about your questioning and study in an entirely non-productive way...that's the first thing you should address.

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    Quote Originally Posted by JeffX99 View Post
    Don't put theory before observation.
    That's beautiful right there.

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    Quote Originally Posted by JeffX99 View Post
    So, long story short...it seems to me like you're going about your questioning and study in an entirely non-productive way...that's the first thing you should address.
    Well, this is because I've injured my hand, and cannot/should not paint or write. So I put theory first... not productive, but better than nothing.

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    I almost feel like this is a hoax thread. In case it's not, or if it is and others would benefit:

    It's because the cap is semi-matte and the light from the monitor is bluish.

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    Quote Originally Posted by LaLaLaLa2 View Post
    And I search a logical explanation for myself and try to understand. That's all. I don't want to annoy you guys.
    Nothing at all wrong with that, and no great harm in annoying some of the guys here, either.

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    Quote Originally Posted by JeffX99 View Post
    you're trying to understand it scientifically and as if one set of rules applies to every situation.
    I don't think there is anything wrong with trying to understand things scientifically. Basically, there is one set of rules that applies, but these depend on light, colour, materials, textures. The theory of ray tracing is your friend.

    However, one must also be prepared to discover and hone these rules, through observation, and I wonder whether knowledge of these rules is going to help your painting skills.

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    Theory and practice go hand in hand. One informs and reenforces the other in a feedback loop.


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    Because for anyone with a trace of an enquiring mind, working from life inspires dozens of questions about theory, which in turn informs their work from life. It's no coincidence that most of the "just draw from life" brigade who I've encountered don't actually draw from life very well at all.

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    Absolutely. Theory evolves from observation and I think it is very helpful in three main ways:
    1) as a way to better understand effects of light, color, edges, etc. when we encounter them the next time we paint
    2) as a means of communication and discussion on what we've observed
    3) as a set of guidelines, reminders or principles that help us to see a little more deeply the truths that may lie within the subject at hand...and allows us a framework to convey that truth in our work

    On a practical note I find it really helpful to read up on theory in certain areas that I might have struggled with that very day (most of the time it relates to values for me). So you really struggled in the field...piece looks like absolute shit...wondering why...read a bit on theory and see where you might be falling down. Next time you go out, don't do that same thing. Carlson's Guide to Landscape Painting, Richard Schmid, Leffel, even Kevin Macpherson's book have all been a major help with one problem or another over the years. Schmid has an outstanding chapter in Alla Prima on self critique and evaluation that can help us figure out where we may have gone wrong.

    You can actually do a great deal of observation and theory analysis when you're not even drawing or painting. Keep asking questions but let observation and problem solving within the experience lead you to the questions.

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    I can only say that after studying color theory more in depth I've been able to understand a lot more about what I'm painting from life. Then painting from life becomes a way to understand exactly how the laws you've learned about apply to real life.

    I also think learning the wrong concepts can be quite confusing for somebody starting out. Stuff like "colors are warmer in the light and cooler in the shadow" will just present an unnecessary hurdle for people to overcome in order to really understand why this might happen.

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