"Of all the arts, abstract painting is the most difficult. It demands that you know how to draw well, that you have a heightened sensitivity for composition and for colors, and that you be a true poet. This last is essential." -- Wassily Kandinsky.
Abstract art, was first used in connection with Russian painter Wassily Kandinsky. Abstract art is highly subjective. Its point is to convey, without using realistic imagery, the feeling or psychological energy of the artist. In its purest form in Western art, an abstract art is one without a recognizable subject, one which doesn't relate to anything external or try to "look like" something. Instead the color and form are the subject of the abstract painting. It's completely non-objective or non-representational. It's much easier to use something 'real' as the starting point for developing an abstract painting, rather than grabbing an idea out of nothing. Look at the photos for shapes and patterns, rather than what the object is. Simplify down the elements, consider alternate colors, focus in on a small part of the photo. Then do it again, and again. That's how ideas for painting abstract art are developed.