Two-Strip Technicolor Inspired Look
Dead simple shader for approximating the look of ‘two-strip technicolor’. A technique from the thirties for shooting colour movies on a budget – no blues, no yellows, no problem 👍
Welcome to any feedback about making it more accurate – I know nothing about vintage photography and film-processing, I just eyeballed it :v
Shader code
//'Two-Strip Technicolor Inspired Look' shader by EHCB, CC0 licensed
shader_type canvas_item;
uniform sampler2D screen_texture : hint_screen_texture, repeat_disable, filter_linear;
uniform float red_boost : hint_range(1.0, 1.5, 0.1) = 1.2;
uniform float green_boost : hint_range(1.0, 1.5, 0.1) = 1.1;
void fragment() {
//grab the screen texture
vec4 screen = texture(screen_texture, SCREEN_UV);
//average out the blue and green channels.
float halfway = (screen.b + screen.g)/2.0;
//apply the boosts and make the blacks slightly green
screen.b = halfway;
screen.g = max(halfway*green_boost,0.05);
screen.r = screen.r*red_boost;
COLOR = screen;
}
