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View Full Version : Chroma vs Value: The Value of Colour


SweetBabyJ
11-12-2004, 12:46 AM
There seems to be some confusion between a colour's chroma, and its value. These are two different characteristics of colour. Many of us have fooled around with watercolour which depends a great deal on a colour's chroma- it's intensity, its "pureness", and we figure that should translate to pastels- it doesn't. The reason it works in watercolour is because the colours are transparent, and you're generally working on white paper. In pastels, however, the colours are opaque- and you can work on any colour paper, because the pastel is going to cover that paper colour right up. (Note: *Usually*- there are techniques which employ allowing the paper's colour to show through- but most folks here are using a technique which results in complete paper coverage within the main figure).

Value is how dark or how light a colour appears in grayscale. Sounds funny, doesn't it- what does grayscale have to do with colour? Answer: A LOT.

Get yourself a piece of red cellophane- it should be around in stores now for the holidays coming up (I know- too early, but that's capitalism at its finest). Grab a piece of white paper- any kind- this is just an exercise- and a bright yellow, a medium bright blue and a medium bright red pastel. Ready?

Make three lines on the paper, one under the other, yellow, red, blue. Make them about 1/4" thick, and make sure all the paper is covered where the line is. Look at 'em. You should not be able to say which is "brighter", more "pure"- they should be equally "pure" as primary colours- right?? This is chroma. You can lay more yellow on, and it doesn't change intensity, it doesn't make it darker; you can lay more red on and it doesn't change intensity, it doesn't make it darker; and you can lay more blue on and it doesn't change intensity, it doesn't make it darker. Now look at them through the red cellophane. What's happened?

The yellow should be nearly non-existant, with the red and blue close to each other in showing up- the blue probably a bit darker (maybe not- depends on how pure your red is). This is value. Red and blue are darker than yellow. Yellow has a light value.

When anyone here says "push your darks" we don't mean add more of the same colour- we mean make the colour darker. How do you do that?

Analogous colours help- those colours next to the primary colours on the colour wheel. To make yellow darker, add orange or green (depends upon what you want, eh?) To make red darker, add purple- but not orange- why? Because orange contains yellow and yellow is a light value. To make blue darker, add a purple- but not green- why? Remember- whatever analogous colour you add to darken a colour, it has to already BE darker than what you're adding to. Make sense?? Add lavender to red, and you won't darken it. Add leaf green to blue and you won't darken it. To darken, whatever colour you add must BE darker already.

If you do not have a dark enough value of whatever colour you want, try this (except with yellow): lay in a light sweep of black- operative word is LIGHT- and then a sweep of whatever colour you want. The black should help darken it, but it has to be done carefully or the black shows as what it is- black. For yellow, try a brown, instead.

Analogous colours work to lighten values, too- just in the opposite way. To brighten a colour, use the lighter analogous colour: Red + orange = brighter, lighter red. Easy. It works with blue just as easily- just make sure you choose which way you want it to go- warmer would be a lavender, cooler would be a green. Then you can lay the proper highlight in in a light-light blue, or a light-light-light green.

Think of colour as a circle- one colour simply changing bit by bit to the next, and it will show you what to use.

khourianya
11-12-2004, 01:10 AM
Thank you so much, Julie. REALLY thank you - you couldn't have chosen a better time to post this!!

SweetBabyJ
11-12-2004, 01:30 AM
Welcome, Cori- there's a lot more to it, but that's a good start. Maybe later, we can get into decreasing chroma, and the relative uses of warms and cools and how to subtly use them.

khourianya
11-12-2004, 02:52 AM
I'll pull up a chair and get the popcorn popping! :D

I've been finding it quite challenging, gettng back into fine art colour theory. My brain keeps trying to think in terms of digital graphics (which is significantly different - you should see my web-safe colour wheel!) So I am absorbing as mch as I can. this is definitely one of those threads that will get added to my subscriptions!

jackiesimmonds
11-12-2004, 06:58 AM
Can I add a coupla thoughts?

When the term "push your darks" comes up, it generally means make your darks more obvious = there isn't enough contrast going on in your picture, the darks aren't rich enough.

You can do as Julie suggests, and use another, darker colour together with the colour you are trying to change.

Or, because you are using pastels, (which are opaque, as Julie rightly points out) and pastels are produced in RANGES OF TONE, if you have used a mid-tone, or even fairly dark tone blue, for instance, see if your kit contains an even darker tone/shade of blue. If it doens't, it may be that you actually need more darks in your kit!!!

Or, you can make more of CONTRAST

If your darks aren't singing out, it may be because they are surrounded by middling-dark-tones - so there is no contrast there. For darks to really read as darks, they often need to be seen alongside a contrasting light area. This will help to reinforce the darkness of the dark area. sometimes, in a picture painted with predominantly light tones, even medium-dark tones will read as "darks" because of the contrast between them, and the very lightest areas. "Dark" can be a relative term.


J

Khadres
11-12-2004, 08:33 AM
When I took a few college painting classes way back when, one of the assignments we had was to sort and arrange color swatches of a red by chroma AND value at the same time (there were over a hundred swatches that came in the kit...not nearly as easy as one would think, but a great learning experience!) This kit came with our only required text, a paperback on the Munsell color system. Not sure if the kit still comes with the book or not, but it's a fun project to play with.

Diane Cutter
11-12-2004, 09:11 AM
When I took a few college painting classes way back when, one of the assignments we had was to sort and arrange color swatches of a red by chroma AND value at the same time (there were over a hundred swatches that came in the kit...not nearly as easy as one would think, but a great learning experience!) This kit came with our only required text, a paperback on the Munsell color system. Not sure if the kit still comes with the book or not, but it's a fun project to play with.
Had to do that too. It nearly drove me bonkers... Too many choices!

Thanks so much, Julie (and J)... That is a great help for me, especially since I have a printmaking and watercolor background. It clears up a lot of the 'why' and 'why not' of colors working...

Diane

*Deirdre*
11-12-2004, 10:20 AM
Thank you so much, Julie. REALLY thank you - you couldn't have chosen a better time to post this!!
Absolutely agree! I'm struggling...but yoiu knew this! :wink2:
Thank you Julie! :wave:

Stoy Jones
11-12-2004, 10:51 AM
Excellent thread SBJ, worth rating! It gets tricky when a yellow in a middle value can often share the same value as a red or blue that is pure...a little shocking discovery a while back that completely threw me for quite some time until I hung around in this forum and learned more about values. Thanks again for this thread!

Stoy

SweetBabyJ
11-12-2004, 11:58 AM
Go Jackie! :clap:

Pastels, see, are made in tints and tones- a "tint" usually meaning white has been added (to lighten the value) and a "tone" meaning black has been added (to darken it). There are some brands which are more "pure" than that, made with the "real" colour without toning (although tints almost always contain white), but they're rare- and pricey. So any "darker tone" of a colour already has black in it; I was assuming you didn't have a darker tone, and would need to "make one".

I fight it tooth and nail because I'm a colourist and I like to see colour sing out for what it is, but IF THE VALUE IS RIGHT, ANY COLOUR WILL WORK. So if you don't have a purple in a medium-dark tone for that eggplant, a blue in a medium-dark tone will work. Honest. Green- *shrug* maybe; you're asking the viewer to suspend some belief, but what the hey, Hollywood does that alla time.

If too often your work is looking not as rich and vibrant as you'd like, start taking the reference pic and your work into grayscale in a photo editing program and you'll probably find it's because you're not going dark enough in your dark areas. "If white isn't light enough, you need more darks"~ Kitty Wallis. It's EASY to lay in the lights- the lights- especially on a dark-toned paper- don't scare us. But think of your painting as a teeter-totter: As light as you go, you've got to go that dark *somewhere*.

Jackie has a good exercise with a strip of a magazine ad in grayscale, which you have to match in colour then convert to grayscale to see if you got it. Kitty has a good one involving assigning different colours to different values in a piece and painting it so that what you end up with looks like pop-art, and dead-on right value-wise. Study some of the work you see here that you like- save the pic, take it into a photo-editing program and enlarge it to see what colours and values are used where- and WHY. Try to avoid black, the colour gray, (as opposed to "grayed colours"- which are something else) and white- use other colours in the correct values and see if the work doesn't start to *pop* right off the paper at you.

prestonsega
11-14-2004, 05:19 AM
Our color theories are based on the light spectrum. Combination of all colors creates white; total absence of color is black... This doesn't translate accurately when dealing with pigments but it provides a framework in which we can plan and predict with some accuracy what will happen when we introduce one color pigment to another. For so long I resisted learning the famous color wheel.....thinking that it wasnt necessary...but once learned, it becomes a valuable tool....thinking in terms of color becomes second nature. But you know....I still find myself in denial that if I mix pretty yellow and beautiful purple that I am going to get ugly mud........ happens everytime but I am sure I will try it again! :D

Julie..thanks for bringing this topic to the forum. None of us ever get too good to review the basics of color as it pertains to painting!

Cochisa
11-14-2004, 05:55 AM
Thank you.
I will copy and paste this post into a text file.
Good info.

Cochisa

Nitsa
11-14-2004, 07:57 AM
You have such a wonderful way of explaining things simply without making the reader feel simple!
I'm not sure I can wait the amount of time it will take you to write your book SBJ......Hurry!

....and TY!

ExpressiveAngie
11-14-2004, 09:27 AM
You have such a wonderful way of explaining things simply without making the reader feel simple!



YUP...Thank you Julie for helping me to see....I totally go by instinct right now but its time to put knowledge to use, thanks again!

AndyfromVienna
11-14-2004, 09:33 AM
:clap: :clap: :clap:

thanks you so much for sharing your experience and knowledge with us ....... i just love reading your threads ...... thank you ...... i love to learn from you .....

*hugs*

Andy

:)

SweetBabyJ
11-14-2004, 01:18 PM
Wow! I'm glad Y'all find information you need in this- to me, it is almost second nature, so much so I no longer think about it- but then when someone needs help with a piece, I realize there's a lot that some folks are fumbling around trying to figure out on their own.

And figuring out things on your own is best- hands down- but it surely is frustrating. Deborah and I have done some putting heads together, and we think maybe an ESP on colour itself and how it relates to pastels might work for December. So fair warning: It may SEEM like December's ESP is far too basic for you to bother with, but I about garuntee everyone will pick up a little somethng they didn't realize they were missing- or that they knew but didn't understand the "why" behind it.

meowmeow
11-14-2004, 01:50 PM
Sitting here nodding...super thread! Thanks Julie, and Jackie too!


sANDY

*Deirdre*
11-14-2004, 02:13 PM
Wow! I'm glad Y'all find information you need in this- to me, it is almost second nature, so much so I no longer think about it- but then when someone needs help with a piece, I realize there's a lot that some folks are fumbling around trying to figure out on their own.

And figuring out things on your own is best- hands down- but it surely is frustrating. Deborah and I have done some putting heads together, and we think maybe an ESP on colour itself and how it relates to pastels might work for December. So fair warning: It may SEEM like December's ESP is far too basic for you to bother with, but I about garuntee everyone will pick up a little somethng they didn't realize they were missing- or that they knew but didn't understand the "why" behind it.
Please do!! I so need that level of knowledge! :wink2: :D

watergirl
11-14-2004, 11:01 PM
Thanks to all! I am diligently working on remedial value and chroma studies...

ann.bun
11-18-2004, 04:24 PM
This is great. I never understood these principles before. Now the question is can i put it into practice?? Thanks very much Julie and Jackie.