#06f — Public Fediverse posts

@troy_s

Okay, so in the normal eye, there are more L cones than any other. Stim the L cones only, with the L cones making up the majority of the luminance signal (with L cone peak being a greenish yellow).

And meanwhile the S cones are not contributors to the luminance channel (any luminance from the display blue primary is due to the stim of the M and L cones).

The sRGB red primary creates about 21% luminance.

The first image is a neutral grey of 21% luminance #868686 against #f00 .(equal Ys, 0 C vs red 104 C)

The second image is #f00 v #860000 (Lc25)

The third is #009494 vs #f00
(equal Ys — 33 C v 104 C)

The 4th is #d11 v #06f
(equal Ys & equal chroma)

Note: Ys is "screen luminance"

----
Some very rough calcs:

#f00 mostly stims L cone to Ys=21.3%

#868686, the values are
R Ys= 4.5
G Ys=15.3
B Ys= 1.5

So #f00
L 16.6%
M 4.7%
L gets 3.5 x more than M

#868686
R
L cone 3.5%
M gets 1.0%,

G & B
Remaining 16.8%:
L 9.7%
M 8.9%
=
L for the Grey 13.2%
M for the Grey 9.9%

L 1.33 more than M