--fx_emulate_film missing

fx_color_presets_preview 0,0,17,7,1,1,1,1,1,1,2,1,1,1,1,1,11,512,100,0,0,0,0,0,3,0,50,50,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
for curiosity are these parameters documented somewhere ?
i think i understand the logic from the gimp plugin but what are all the last ones doing (after 50,50…)?
other thing : what’s the point of normalizing colors before/after/both.

great collage option!