Continuity mistake: When Ray starts to levitate in John's house, he looks down and he is hovering right above the table with the couch to his right. In the next shot, the table has suddenly vanished and it's now showing that the wall across from the couch with the TV and chair are on his right. (00:20:25)
More quotes from Freedom Fighters: The Ray
Answer: My understanding is the Ray uses pure light for his powers while Superman and Supergirl get their power from the solar energy of a yellow sun, not yellow light.
Bishop73
I see. But if it was from pure light, wouldn't his powers have a white glow and not a yellow glow?
Quantom X ★
Most likely just a styling choice. I just know the basics details of his powers and not sure why it comes out yellow (or if it's even stated.) Perhaps for the the same reason the sun appears yellow, short wavelength light becomes scattered.
Bishop73