Is it possible that phaser color in the 23rd century corresponds to different frequencies? The 1701 Phasers were blue when the ship battled Control with Discovery (and those were the 'new phaser upgrades' per what number one said to Pike). Also, when the 1701 crew were thinking of methods to divert the comet, it was mentioned that if the harmonics were set to higher frequencies, they could shatter the forcefield. So, its possible different frequencies correspond to different phaser colours (which would actually be consistent with how ENT-D phasers behaved when Data was told by Shelby to rapidly cycle through the frequencies to remove the Borg Cube's tractor beam in BOBW)... obviously. since then, phaser colour remained more or less constant (orange in the series and more reddish in the movies).