Further disclaimer: I'm LEARNING, not a teacher. This post is the result of a conversation that just needed pictures. :-)
This is a prime example of why you look at the colored pencil POINT rather than the color painted on the barrel of the pencil to see what color it is. You shouldn't completely trust those sly colored pencil manufacturers!
(This is Prismacolor Scarlet Lake - 923)
All of the following examples are done with prismacolors.
What I did -- took my jumble of colored pencils and semi-randomly made some nice colored squares on a small piece of Stonehenge paper.
I scanned them in color, then switched the scanner to grey scale and rescanned to see the actual color values.
The top two rows -- Pink (929), Orange ( ), and Rosy Beige (1019)
then Pale Vermillion (921), Canary yellow (916), and Apple Green (912)
It's easy to look at the colors and see how the Pink and Pale Vermillion and Orange are near values, but when you look at the grey scale you can also see how the Orange and the Apple Green are nearly the same value even though they are very different colors. So we can figure out that if an entire drawing is done in colors of all similar value, it is going to feel kind of washed out, even though the colors themselves are really nice.
These are the bottom two rows. I was a bit surprised at how light the blue in the upper middle showed up; I would have thought it was a darker value than it appears here on the grey scale.
The colors are: An Olive Green That I Just Dropped Which Then Rolled Under The Desk So It Is Now Irretrievable, Electric Blue (1040), and Scarlet Lake (923)
The bottom row: Violet (932), Imperial Violet (1007), and Dahlia Purple (1009)
This really shows how, even though the red is BRIGHT, it is a dark-ish value. It can brighten up a dark passage without changing the value a whole lot, but if you're going for RED IMPACT, it might get lost in near values. And, comparing the temperature of the colors on the bottom row, you can see how there can be a neutral purple, cool purple, and warm purple.
Sigh. At least that's how I figure it is. Books, books, books, study, study, study, and practice, practice, practice. That's the trick.
And for those of you who always want to know what music I'm listening to, I've got Jeff Buckley's "Grace" album playing now -- I'd forgotten all about how wonderful he was until I caught that cute kid with dreadlocks on American Idol singing the Buckley version of Leonard Cohen's "Hallelujah". Yep, I decided to watch a little American Idol this season to finally see what all the fuss is about. Not near as good as the Rock Star shows have been, but getting reminded of this beautiful album was well worth the time. So iTunes scored a sale off of me because of the show -- they should be happy! :-)