This image seems to have some flaws. I did think the sky was clear and the water rippled (from the details int he bottom left) and I said the both birds where white because the yellow in the one on the left looks only to be from light and not feather color. However, it seems other people have different interpretation, which skew the validity of the test.
Still, this test was interesting for me. In a class I am in we did some working memory tests done on chimps and my professor thought my high scores might indicate that I have and a eidetic memory, which would be neat; I always assumed my visual memory was the same as others. Also, tangentially, people born with eidetic memory typically experience a decline in the strength of their eidetic memory as they get older.