1. An image capturing apparatus comprising: an image sensor including an imaging plane that receives an image of a shooting target field through color filters according to two or more wavelength regions and outputs a signal of the image of the shooting target field; an attitude detection circuit configured to detect an attitude of the image capturing apparatus; and a processor configured to set a larger weight for a wavelength region having a higher image forming performance than for a wavelength region having a lower image forming performance in accordance with a direction based on the attitude of the image capturing apparatus detected by the attitude detection circuit, generate image data based on the signal output by the image sensor, and detect an object in the generated image data.