Most readers look at the photograph first. If you put it in the middle of the page, the reader will start by looking in the middle. Then her eye must go up to read the headline; this doesn't work, because people have a habit of scanning downwards. However, suppose a few readers do read the headline after seeing the photograph below it. After that, you require them to jump down past the photograph which they have already seen. Not bloody likely.
David OgilvyIt has been found that the less an advertisement looks like an advertisement and the more it looks like an editorial, the more readers stop, look, and read.
David Ogilvy