however, these strategies are lost on a considerable portion of our population the colourblind. jeff revell is a photographer who is based in washington, d.c. jeff mentions that red and blue are the worst colour combination for him to have together. then too, he finds this colour combination everywhere. for him, it looks like the blue vibrates inside the red, which gives him a headache.&rdquo revell is one of those redgreen colourblind people, and distinction between colours is hard for him. shades that are blended with green or red, like brown and purple, all look the same to him.