Cody - A simple dismissal is "it is an anachronism"
As with many CS/CE tools of art, it originated as a first approximation to correct a mismatch between what was desired/needed and what was available.
It is "simply" a first order model of the nonlinear difference between recording/display physics (originally film, then CRT, then "all" forms of digital recording, encoding, compression, playback, printing, etc). These "nonlinearities" are then convolved with the nonlinearities of vision (both in luminance and chrominance) Along the way the "wisdom" of the veterans who explcitely knew how to use that model became *implicit* in the tools and techniques and became (borrowing glen's word) somewhat occult to those who used it later.
I had the good/bad fortune of working with film recording in my early career which made me acutely aware of these issue, especially as we tried to resolve film (transmissive) exposed by and recorded from CRT (stroke) images against CRT (emissive) displays (early color monitors) against print (reflective). A simple exponential (gamma) curve is useful in this but far from complete or accurate (models: wrong Vs useful).
Steven's Power Law refers to psychophysics of human (and all vertebrate/Neuronal?) perceptual systems across all sensory modes. Combine (convolve - compose multiple power laws) that with the recording/storage/display physics (of light) and you (conveniently) get a single exponent (Gamma). Then run that through hundreds of thousands of geeky scientists and engineers and tech dweebs and tech marketers for about 40 years and *bob's your uncle!* (whatever that means) Gamma!
Ed may well have a much more eloquent (and historically/technically accurate) answer.
On 11/26/25 10:59 am, cody dooderson wrote:
I have been going down a rabbit hole trying to figure out the origin and purpose of the Gamma Color Space. In Unity, it is usually turned on in some obscure checkbox. I can only assume that the intention is to enrage graphic designers. So far, each article and forum I read makes me more confused. Does anyone actually understand the reason for Gamma Color Space. Is it really based on some experiments now called Stevens's Power Law? and does Guerin know anything about a power law that shares his name?_ Cody Smith _ [email protected] .- .-.. .-.. / ..-. --- --- - . .-. ... / .- .-. . / .-- .-. --- -. --. / ... --- -- . / .- .-. . / ..- ... . ..-. ..- .-.. FRIAM Applied Complexity Group listserv Fridays 9a-12p Friday St. Johns Cafe / Thursdays 9a-12p Zoomhttps://bit.ly/virtualfriam to (un)subscribehttp://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIChttp://friam-comic.blogspot.com/ archives: 5/2017 thru presenthttps://redfish.com/pipermail/friam_redfish.com/ 1/2003 thru 6/2021http://friam.383.s1.nabble.com/
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