Homework / test English to French Tech/Engineering Photography/Imaging (& Graphic Arts)

Bonjour,

Type de document: notice explicative du fonctionnement d'un appareil d'étalonnage de projecteur et réglage des différents paramètres.
Cible: francais (France)

Quelle est la traduction exacte et correcte de "gain" dans ce texte?
La phrase est la suivante :
"Measurement and Gain Adjustment
By changing the Gain in our projectors, we can change the amount of Red , Green and blue reaching the screen"

résumé plus tard dans le texte en ces termes :
"More gain for a particular color, means more of that color, less gain means less color."

Plus tard dans le texte :
"You might ask, if gain controls the proportion of color at all IRE levels, why do I need to make a whole series of measurements, wouldn't just one do? The answer is that if things were adjusted perfectly, that's all that would be needed, but there are several things that can go wrong and seeing that the light output for the three colors "track" each other properly is one important test of the projector's overall state of calibration. "

Merci