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Ger <No.### [at] Thank You> wrote:
> I'm wondering how you calculated the color/brightness/size of the stars.
The BSC4 contains magnitude and color index data. The color index, or B-V, is
the difference in magnitudes through different colored filters.
The color was reconstructed by mapping the B-V to a temperature, which was then
converted to a black body color. All credit for the black body calculation goes
to Ive. See the thread "NOMAD test--the Pleiades" for more information about
the B-V mapping.
The brightness was a straightforward magnitude-to-linear conversion:
(100^0.2)^(-magnitude) * an arbitrary constant
I then subtracted an extinction constant, as noted.
The "size" of the stars in the image is a proxy for brightness, to compensate
for the low dynamic range of the visual medium. It is the outcome of the
falloff function I used for the media containers.
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