In normal sunlight, shoot three color plates of black, white and gray with camera P file, all of which are gray. Is there a professional to answer? . .

This should be the problem of exposure, not the camera's poor performance or any defects.

Digital cameras don't know the color, they are color blind and can only perceive the light ratio. The photographed color is the color calculated by the central processor through the calculation method designed at the factory after the photosensitive element records the red, green and blue wavelength data respectively. In the color sample of PS, you will find that the transition of black, social and white can appear at the far left of any color area. There is no color information in this area, and the values of R, G and B are all the same. Simply put, this only records light and dark (gray) information.

From the camera's point of view, there is no color information that can be calculated for the three "colors" of black, gray and white, while the "P" file (automatic file) automatically calculates the aperture and shutter matching to obtain the correct exposure, so that the reflective dark (black) camera will increase the exposure, while the reverse bright (white) camera will reduce the exposure. Naturally, it will not achieve the effect you want.