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Re: Double hires mode color artifacts

Linards Ticmanis wrote:

Dirk Thierbach wrote:



But neither gives a "brown" color for number 8. You can make it
into brown by shifting for 40 degrees or so, but that will distort all
the other colors. Shifting for 10 degrees or so will leave the other
colors mostly intact and will give you a sort of greenish-brown, but
that's all.



Just FYI - my physical Apple //e also gives a noticeably greenish kind
of brown for COLOR=8, though admittedly not quite as green as the one I
calculated.

In an emulator, it might be nice to simply have virtual "hue",
"saturation", "brightness" and "contrast" knobs. In real hardware I
usually use yellow as a reference for adjustment; in my experience,
yellow is the first color that starts looking wrong with a bad adjustment.


And, interestingly, color 8 is "dark yellow"--the same phase as
yellow, but with luminance 1 instead of 3--in other words, a
low-luminance red-green (= yellow).

So I'm guessing that the reason for its slightly "more green" appearance
on a modern RGB display is a difference in phosphors and gamma.

-michael

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Home page:  http://members.aol.com/MJMahon/

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