C.T.B.
C.T.B. stands for Color Temperature Blue. This is an abbreviation for the color correction gels used in lighting to convert the color temperature from tungsten to daylight. They come in gradients: Quarter Blue, Half Blue, Full Blue.

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C.T.B. stands for Color Temperature Blue. This is an abbreviation for the color correction gels used in lighting to convert the color temperature from tungsten to daylight. They come in gradients: Quarter Blue, Half Blue, Full Blue.