Nearly every photo I've seen of MLK is in black and white. Looking on google colour photography for the average person became popular in the 60s and MLK was killed in 1968. It seems strange that we could land someone on the moon the year after but have barely any colour photos of MLK.
My sister suggested it's done on purpose to make the civil rights movement seem more distant when it was only 40ish years ago. But is this true?
There is a very simple answer to this, color photography was expensive and was not suitable for use in daily media until the late 1960s for television, and much later for print media.
Most media photographs were taken for daily newspapers. Color printing was expensive, and primarily used only for Sunday comics supplements, so photographs printed by the papers were monochrome. Stills taken from television films were monochrome before 1965.
Most people taking photographs for themselves used monochrome film well into the 70s simply because processing color film was more expensive.