The Cokin Blue (82C) Colour filter is for use with a film camera using daylight colour film or a digital camera in "automatic" mode. The Blue (82C) Colour filter has the strongest effect of the 82 Series cooling filters (almost eliminateing the red-yellow cast at sunrise or sunset). The Blue (82C) Colour filter increases the colour temperature from 2800ºK to 3200ºK. The 3 filters, Ref 023/024/025, can be combined one with the other.