In my outdoor photography, I try to capture special effects caused by atmospheric conditions, seasons, or time of day.  While exploring landscapes, I also look for subjects that provide the basis for abstract designs from natural objects.  Digital painting techniques are sometimes applied to photographs to create interesting effects.  In a very different series, I do alterations to enhance close-up photographs of interesting features on old cars.

I don't concentrate on just one type of subject, but watch for what might make an interesting photograph, such as wild flowers, rock textures, or fireworks.