1. A solid state imaging apparatus, comprising: a pixel array in which pixels arrayed in a matrix shape, with each pixel having a color filter of one color, and including a plurality of photodiodes each of which receives an incident light passing through the color filter; and an adding circuit, wherein the pixels include a first pixel, a second pixel and a third pixel, each of the first pixel, the second pixel, and the third pixel has a color filter of a first color, and the adding circuit performs addition of (i) a signal based on an output of only a part of the plurality of photodiodes of the first pixel, (ii) a signal based on an output of the plurality of photodiodes of the second pixel, and (iii) a signal based on an output of only a part of the plurality of photodiodes of the third pixel.