It appears when the time travelers are tumbling through space towards the Titanic at sea, the footage has been tinted -- at least the sky and water. The ship striking the iceberg scene is viewed by the Time Tunnel controllers on a black and white television screen, so the footage didn't need to be tinted. I would imagine in 1966, the footage was combined in an optical printer using colored gels to make the colors of the sky and water. There were no computer-generated effects in 1966 like today. Robert H. Gibbons