Luigi Ponti wrote: > I just ran into this page > http://geography.uoregon.edu/datagraphics/color_scales.htm > > that includes, among others, precipitation color tables. I > don't know if that can be useful. > > The page of this Lab also provides an interesting paper titled "End of > the Rainbow" which elaborates on why one should not use continuously > varying color schemes (and absolutely no rainbow color table). The way > to go seems to be banded color schemes -- a color scheme with equally > sized bands of constant color [1]. ... > [1] Borland D, Taylor II RM (2007) Rainbow color map (still) considered > harmful. IEEE Computer Graphics and Applications, 27, 14-17.
In matters of human perception the individual experience is not subject to hard rules. Of course it is important to think about how the color- blind will see things and how it will look printed in greyscale, etc. An interesting subject to me, thanks for the link/look forward to reading it. It reminds me that I still need to read "How to lie with maps": http://www.eyrie.org/~eagle/reviews/books/0-226-53421-9.html (in the spirit of "How to lie with statistics") It is really quite amazing/scary how much changing the colors affects the interpretation and is able to hide/highlight features. After spending a fair bit of time with the issue I personally feel it is most honest to use a color scale which can be described as a continuous mathematical function. e.g. log()+BCYR or something directly based on the univariate stats of the data. -> Take the biased "what looks nicest" human out of the picture. Choosing arbitrary band limits on a continuous value dataset just compounds the opportunities for arbitrary human influence. The statistical equivalent is to slowly vary the number bins in a histogram while the peaks seemingly double and halve. ...so it is up for debate :) > As I side note I was wondering how to draw such a color scheme (i.e. > with equally sized bands of constant color) in GRASS. declare the number twice, e.g. r.colors color=rules << EOF 0 red 100 red 100 yellow 200 yellow 200 cyan 300 cyan 300 blue 400 blue EOF Hamish _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
