Re: fluorescent colors in colorsync environment
Re: fluorescent colors in colorsync environment
- Subject: Re: fluorescent colors in colorsync environment
- From: Igor Asselbergs <email@hidden>
- Date: Tue, 10 Jul 2001 09:10:34 +0200
C. David Tobie wrote:
>
If I use a good digital camera to shoot fluorescent objects and print to an
>
Epson inkjet, I get some amazingly bright colors, but "fluorescent", by
>
definition, means colors beyond what can occur from the amount of light
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available in the proper band of the spectrum, and stealing light from other
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bands to increase emittance. That requires fluorescent inks to accomplish...
>
and is beyond standard ICC profile definitions, as they don't deal with
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spectral data, only Lab values.
Actually I have my doubts. Regarded from an environment of measuring and
computing you're absolutely right. But regarded from the realm of perception
I don't think your statement is necessarely true. As I explained before it's
easy to photograph fluorescent colors, it doesn't need any special
equipment. Within the boundaries of the picture the colors are really
fluorescent, outside the picture they are just ordinary colors. In my
experience colors are highly relative. Measuring and computing is only part
of the story.
For me it's important to be able to relate normal colors to fluorescent
ones. How much lighter is fluorescent yellow, related to normal yellow?
That's imformation I can use to adjust a picture. But for now that's outside
the scope of colorsync. I'm using X-rite's colorshop to do the trick.
BTW: Even the brightest fluorescent colors I can come up with appear to fall
within CIELab space, according to colorshop (though I must add that
colorshop has a max intensity of 125 percent per waveband, wich is too
little for some fluorescent colors). That makes sense to me because while
part of the spectrum has a reflection of more than 100 percent, other parts
are still absorbed. Overall most fluorescent colors are probably not
brighter than white.
We tend to regard rgb 255 255 255 as white. You might just as easely regard
these values as being fluorescent. It all depends on the environment in wich
these colors are perceived. Wich brings me to the thought that as long as
brightness is not defined in the whitepoint, no one can tell if a color is
fluorescent. After all: fluorescent colors are supposed to be brighter than
normal. But what is normal?
Igor Asselbergs