From: Benjamin R. <ben...@ou...> - 2015-02-23 18:39:14
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My eyes are definitely favoring the L20-80 over the L5-95 colormaps. Does Luminosity take into account human's non-linearity in perceiving brightness? I remember a few years ago many of the open-source graphics tools (such as GIMP) had to be fixed because it assumed a linear brightness perception. IIRC, humans are better at perceiving brightness gradients on one end of the range than on the other end. On Mon, Feb 23, 2015 at 1:30 PM, Eric Firing <ef...@ha...> wrote: > On 2015/02/23 8:16 AM, Benjamin Root wrote: > > Interesting choices, and I think we are on the right paths (no pun > > intended) through the two possible colors. However, I think the same > > problem arises that I noted before. Both ends of the colormap are nearly > > black to nearly white. IIRC, our perception of luminosity has a much > > greater range than it does for chroma. While it is nice to take > > advantage of that, I wonder if we are going too far in the luminosity > > range? Perhaps these colormaps would be better if the luminosity range > > wasn't as full as it is here? > > > > Ben Root > > Ben, > > I was noticing the same thing, except that at least on my screen, the > problem is mainly at the dark end, and it varies with the actual set of > control points. The very last one, for example (Purple Red Yellow > L5-95) has what looks like a fairly linear ramp from end to end on my > screen, while "Blue Green Yellow L10-90" lacks contrast on the dark end. > I suspect all this will be quite dependent on the particular screen > (or printer--including the whole chain of color conversions ending up in > ink or toner dots) being used. It doesn't look to me like a problem > with the luminosity range as such. We have a highly nonlinear problem > here. > > In any case, this looks like a nice tool. Maybe it can be combined with > Nathaniel's code, which shows other aspects of the colormap? > > Eric > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > > http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk > _______________________________________________ > Matplotlib-devel mailing list > Mat...@li... > https://lists.sourceforge.net/lists/listinfo/matplotlib-devel > |