Is there a better color scale than the "rainbow" colormap?

Question

I am plotting a series of curves in x, y space, where each curve is identified by a scalar value z. I wish to map the z value to color for each line, but most colormaps / color tables are constructed with images in mind (e.g. on a white backround, the grayscale colormap hides one extreme of z).

The rainbow/spectral/jet colormap - which is the default in many plotting programs - is better, but suffers from poor visibility for the yellow/cyan lines on white backgrounds, and poor color contrast among the blue/cyan/green colors. Borland and Taylor further discuss this and other problems with the rainbow colormap:

• Borland and Taylor, "Rainbow Color Map (Still) Considered Harmful," IEEE (2007). [pdf]

Can someone recommend something better? Some aspects I'm looking for:

1. High visibility for all colors against a white background
2. Intuitive perceptual ordering (red-yellow-blue makes more sense than red-blue-yellow)
3. Good chromaticity contrast between colors

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Edit/update: per endolith's request, here's a simplified sample plot: The "gray" colormap and it's relatives (starting at black and ending at white) are designed for images, however when used to plot lines or points on a white background, some will be hard to see or invisible. The "jet" colormap and it's spectral relatives typically also have a yellow, green, or other color that is hard to see on a white background.

Answer 1

Perceptually improved colormaps has several variations of rainbow colormaps with constant luminance or luminance that increases monotonically, with some documentation at The rainbow is dead…long live the rainbow!:

Dave Green's `cubehelix' colour scheme is a rainbow colormap "intended to be perceived as increasing in intensity .. from black to white, deviating away from a pure greyscale (i.e. the diagonal from black to white in a colour cube) using a tapered helix in the colour cube, while ensuring a continuous increase in perceived intensity". You could cut off the white end to make it suitable for a white background.

CMRmap.m "we devised a colormap that preserves colors, but mixes the color components so that the black and white rendering of the colormap produces a grayscale representation that is monotonic with intensity". Again, you'd have to clip off the white end: