Friday, September 16, 2011

Part 3, Gamut Masking Method

Let’s see how the gamut masking (or "mapping") method actually works, using the example of that bright colored Las Vegas scene.


This video walks you through it, step by step.

(Video Link) By comparing the three paintings below, you can see how the two smaller paintings were shifted to the warm and cool.


Note that underneath each of the two shifted paintings is a set of nine swatches. Those are the subjective primaries carried through three values each. Each of the paintings was done with those carefully limited subjective primaries, leaving aside the tube colors. Note also that two of those primaries are the same: the green-cyan, and the red-magenta.

The wild card is the yellow in the top one and the blue in the bottom one.

Now look at those three swatches connected by arrows. The color note that appears as the blue sky in the warm scene is almost exactly the same color as the color that appears yellow in the cool painting. Both are basically a neutral gray. It’s a subjective secondary belonging to each of the two gamuts.

I’ve out lifted those swatches out of the smaller paintings so that you can see how they look out of context. I’ve also lifted a swatch of the “yellow” from the cool painting and put it over the yellow shoe in the original painting.

It’s hard to believe that a neutral gray could appear either blue or yellow.


These are weird mixtures, and you wouldn’t think of using them unless you forced yourself with the gamut masking system.


This is reminiscent of the colored cube illusion we’ve seen before, where the red and cyan squares look different, but they’re both really the same gray.

This little demo will be part of an article that I wrote, which will be appearing in the upcoming fall print issue of American Artist’s Plein Air Painting magazine.

Previously on GJ:
Gamut Masking, Part 1
Gamut Masking, Part 2
 Colored Cube Illusion (aka "Color Constancy")
2008 post on color masking

A free online gamut masking tool for digitally minded artists by Richard Robinson

You can order the book "Color and Light" by mail from my online store and get it signed, or order from Amazon below.

36 comments:

Zeitwolf said...

extremely helpful, thank you very much!!

Drew said...

Oh man, this helped clear up a lot of confusion on it. I read through the blogposts and book chapter several times and I still felt like I wasn't quite getting all of it. Thanks Jim for the video.

When it comes to premixing the values for the chosen colors, do you typically stick to three, or does it vary depending on the needs of the painting? (I think I know the answer to this...)

And I can safely say that if you were to ever put out a dvd of a painting video much like Donato's, I would buy it in a heartbeat.

Steve Somers said...

Okay, so it’s basically the same as pre-mixing the color strings like you did for the 30 minute portrait studies, except these colors are based off a pre-chosen gamut, as opposed to being selected from local colors in nature. The challenge is to mentally make that translation from local color to the new gamut. Think I’m ready to give this a shot. Thanks for the post!

Adam Hreha said...

Thank you, James! The color gamut is by far my favorite topic from "Color and Light". Your approach seems so much more simpler compared to other books on mixing palette colors. Seeing the process in motion is very enlightening. Well done.

zoe said...

Mr. Gurney,
Am I right in thinking that you don't mix your primaries with black to get lower values for the initial color strings? Instead, we should seek out the lowest value in full saturation (i.e., a dark brown instead of a yellow mixed with black)? It would also imply that you get to neutrals only by mixing complements, and never by mixing a primary with gray...

Daroo said...

Thanks so much for this! Great Video. Love the dollies.

The YURMBY wheel is so helpful because it shows you that the most neutral gray will work as a yellow (in the cool version) because it is the least blue and the least red. Being able to see a color's relative position in the color space is a tremendous tool for understanding relationships.

The tough part for me is evaluating the darkest value tube colors and placing them on the wheel properly. Turning it around, how do you guard against having too intense (out of gamut) colors in the deepest values?

Alonso said...

awesome, great to see it in action makes it more clear, thank you! I swear I had read your entire blog archive but those older posts must have gone over my head the first time.
So do you determine what value range you want to work in before you mask your wheel, so you start with a wheel biased bright or dark?
So you choose colors based on relationship? A red violet in your cool gamut, comes out as red gray in your warm gamut? A little mind bending going inwards instead of down.
Thanks for the post!

Jeff said...

Thanks for showing this with a video. I've read about gamut masking on your blog before and in your book but I never really understood it. The video makes it completely clear.

arturoquimico said...

I am a chemist and for us brown and gray do not exist as colors; yet I am always amazed at how portraitists are able to start on one side of the head say in shadow or blue, or the other side in sunlight and end up at the same "color" in the half tones. Not one artist in the years I have studied portraiture could explain it... "Color and Light" and this video finally do! Thanks..

अर्जुन said...

It may be but a pellet cast upon this rabbit trail, nonetheless ~

pree not pry, follow:

Luis Prima

prima donna

alla prima

imprimatura - first layer, an early stage of development, sorta like 'premature'

Cheers!

Petr M. said...

This is a great, no-nonsense method. I'm currently working on applying it to pastels (where there are no tube colors as we know). The challenge here is how to keep within a gamut by choosing the right premixed colors. Has anyone tried that already? Any lessons or tips to be shared? Thanks!

Chris Vosters said...

Thank you for this insightful post. It's always surprising to see how imposed limitations can change an artist's result for the better.
There are far too few blogs that venture into these technicalities, and i'm glad yours does it so well.

Arnaud said...

Enlightening! You were right, James, nothing replaces a video (or real life) demonstration.

Orlando "Holtzmann" Medeiros said...

Another very interesting video, James! Sound mixing was a bit off early on, everything was shifted to the left channel, for some reason; but it ended soon enough that it didn't detract from the content of the video.

My teacher actually tried to each us this method when I was taking art classes in elementary school. I don't think any of the whippersnappers in the crowd -- me included -- actually understood what she was talking about. The two examples in this video make it much clearer!

James Gurney said...

Thanks, everybody. This is one of those topics that’s easier to show in a video than to explain in a book, so I’m glad it makes more sense now.

Here’s a run at your questions:

Drew: Thanks. I usually stick to three or two. It’s easier to conceptualize the gamut as a triangle. Two is good as well, but then the gamut not so much a two dimensional shape as a line or bar across the color wheel, basically a continuum between to contrasting colors.

Steve: you said it exactly. Premixing gives you the colors in all the values you need, and that color range becomes your subjective universe for that painting.
Zoe: Nothing wrong with black, but I generally use other colors to gray or darken colors. With yellow, black can shift the hue to green, so you need to use other colors to “steer the tone in the right direction anyway.

Daroo: the dolly shots were done with the camera strapped to a bicycle. I just try to eyeball the chroma on dark mixtures, and as you could see in the video, my color mixing is fast and improvisational, not as methodical as some people. It’s OK to have some slop in the mixtures, too, and sometimes I reach a little outside the gamut if I need to.

James Gurney said...

Alonzo, it is mindbending, and one color in one gamut can be something entirely different in another. I often find it helpful to just assign each corner in my mind as “red” “yellow” and “blue.” You raise another important point. The premixing doesn’t have to be the full value range. If you’re doing a high key painting, you would be working within a value gamut, too, and your premixtures could anticipate that.

Thank you, Arturo. Brown is a funny color, because we don’t have a name for yellow in its dark value ranges. “Brown” comes the closest, even though we think of it as a more neutral color.

अर्जुन: Primo!

Petr: Yes, this system doesn’t work quite the same for pastels or transparent watercolors. There I suppose you’d have to limit the gamut with the “tube” colors or the pastels themselves. But in watercolor you could mix up little bottles or dishes of your ingredient colors, adjusting them to fit the gamut.

Thanks, Arnaud and Chris.
Orlando, Yeah, sorry about the sound. I plugged my mike into the wrong slot for the second half of the VO, so it defaulted over to the camera’s mike, which was not so good.

Don Ketchek said...

Gamut masking definitely offers some interesting ideas on creating color harmony.

It seems like the creation of a gamut mask is somewhat arbitrary, but I wonder if there is any way to interpret an actual photo and determine its color gamut range. Do any of the photo imaging programs (such as photoshop) have the capability of analyzing a photo (or any image) and creating a gamut mask of the colors used? I would think such a gamut masking tool would be very helpful in analyzing photos and creating a less arbitrary color palette for the artist.

James Gurney said...

Don, if you try couleur.org, by P. Colantoni, there's a digital interface (Windows only, I think) that lets you upload a jpeg and play with various ways of visualizing the gamut, including in three dimensions.

I've done a few posts about it, and on my YouTube channel, there's a video of some of the 3D gamut animations revolving in space. It's definitely mindbending.

Mathias said...

Extraordinary clear explanation! It helped me understanding things that I would do (but very awkwardly) without truly understanding.
I think this video will help me through my next experimentations in colour.

Thanks a lot.

Sean Hayden said...

Great to read/watch this post.
interesting and helpful as always

Cheers for posting such an inspiring blog!

Euna Kwon said...

This is gonna help a lot for my underwater scene I was struggling a lot. Thank you very much.

Sam Easton said...

This theory will same me a lot of $$$ in the future. I used to eyeball my colors, which can sometimes results to a lot of 'useless' paint. Danke a bunch!

Michael Pieczonka said...

Awesome video James.. thanks for posting this and it is great to see some of your technique in action!!

Mark Heng said...

So great to see your working method and to have these concepts explained so well...Do I see a DVD release in the future?

Diane Dawson Hearn said...

Recently I've been studying limited color palettes and have really enjoyed this ides of the Gamut masking method here and in your excellent book, Color and Light, but I have a question. I see how you pick three colors to be your "primaries" and then make a triangle mask, but I noticed that within that gamut triangle there are sometimes colors that could not be mixed with the three chosen colors that formed the triangle mask. For instance, in your video you chose the dull red and dull green and blue, but within the mask I saw a magenta that could not have been made with the colors you chose. Can you use any color that appears within the mask even if it isn't one that could be mixed with the chosen colors that made the mask, or is it better to stick to the chosen "primaries"?

James Gurney said...

Diane, you're quite right, and that's a very insightful question.

Theoretically you can choose any two color notes from the infinite variety on the color wheel. The intermediate mixtures from those two color notes should in theory be located on a straight line between those "primary" color notes. In practice, though, that line is often not straight, because of the behavior of paint pigments.

So I'd say, yes, you can do whatever you need to do to mix the colors that you actually find within the triangular gamut. Even with an outside assist, the resulting gamut should give your painting the harmony you want.

Schnider said...

Sir, do you also use gamut when painting from life? Or is it only applicable to paintings that are done from imagination?

James Gurney said...

Not usually when I paint from life. I sometimes work with a pigment-limited palette at a model session. The time I use gamut masking the most is when I need to control the gamut for color scripting a long illustrated book or film. After you do it a bit, you can do it mostly in your head, mixing the strings without necessarily actually arranging the gamut masks over the color wheel.

Jack said...

Hello Mr. Gurney,
What is the BLAST acronym you have attached to the upper left of your palette? I couldn't make out some of the parts on it, but I'm pretty intrigued from what I could. They look like solid things to keep in mind while painting, and an excellent insight into your process!

James Gurney said...

Jack--
(B.L.A.S.T.) stands for:
Big brushes.
Large to small.
Accents last.
Soften edges.
Take your time.

Or, to explain a little more:
1. Use the biggest brush possible for a given passage.
2. Paint large shapes first, followed by small shapes.
3. Save your tonal and chromatic accents until the last.
4. Try to soften any edge that doesn’t need to be sharp.
5. Take time to get the center of interest right.

More at: http://gurneyjourney.blogspot.com/2009/01/blast-rule.html

Groupdmt said...

I really appreciate the idea behind this great post.You are doing a fine job.Keep it up.
Cartoon coloring

Michael Tshikaya said...

Hi James, this helped me clear up the way in which you actually use the gamut on a painting, i.e the way in which you substitute your colours, so that the hues are basically the same, but the chroma changes, I think in your book colour and light, it wasnt clear, at least to a beginner, how to take the masked colours and for example turn one painting into a painting using those colours; what i mean is, it wasnt clear how you knew which colours to put where in your new painting, but now i can see that its pretty obvious, that if your first painting had reds, you would use the closest to reds on your gamut in the new painting, maybe it was just me that missed this? The cube illusion is unbelievable, i had to test it in photoshop, and its mindboggling, and shows the difficulty of mixing accurate colours from observations, but knowing this is alreayd useful for watching out for the same effect when actually mixing colours

Janet Oliver said...

I'm giving myself an intense tutorial on Gamut Masking and Mapping using your methods. Today I took a black and white photograph and traced two separate drawings of it. Then I mapped a warm gamut and mixed my colors. I wanted so badly to introduce a tube color after mixing, but I trusted your advice and curbed that desire. I'm so glad I did! There's nothing like doing something for oneself to see the value in it! Tomorrow I make the same painting using a cool gamut. Thank you a million times!

Janet Oliver said...

I forgot to add that I am following BLAST to the letter!

James Gurney said...

Janet, that sounds like a great exercise. I'm so glad it's working for you. Good color really does take discipline, like walking through a candy shop and just buying one peanut cluster.

Rali Van Minks said...

This actually a part I got a bit stuck while reading the book, but the video and the way to go about gamut mixing solved all my questions. Really enjoying Color and Light and can't wait to apply everything I've learned so far, both traditionally and digitally. Thank you for the wonderful books you've released, the great content of this blog and for all the wonderful insight you share with us James!