I took two pictures of two different flowers with portrait setting. One came perfectly exposed with dark background, the other seems over exposed with brighter background. I tried it again and the same result! Does the color of the object make the camera select wrong exposure? If yes, what is correct technical term for it. How can I fix such photos. Apparently problem is with non white colors only.
Portrait setting Nikon D5100 (the background is nice dark. In reality it was not dark at all)
Portrait setting Nikon D5100 (background is bright, more correct to what really it was but the flower seems to be over exposed. The focus was on flower)