Finding Your Photographic Subject

Door Knockers in France and Germany

The number of subjects or themes for a photographic project is unlimited. You start noticing something in your little world that attracts your attention and you take  a first shot, maybe a second and a third and you are in the wheel.
A relationship has begun and from now on you feel a reason to coninue. Some photographers have a theme that seems to stay with them for their entire life.
Ansel Adams and the fantastic black and white  landscapes photographs he took in the Yosemite Park would be one of my favourites. Other photographers created collections of buildings during their life like the famous Bernd and Hilla Becher. Others shoot birds with their camera, or fish in the sea.
Sebastiao Salgado as a final example worked for over a decade on a project called "Workers" where he travelled all over the world to take photos of people working in different fields, projects, expertise. One of the best photographic projects I ever saw.

Once you get into a certain depth of your subject you will become an expert sooner or later. You start developing interest in all aspects of the theme and research will lead you into new levels of knowledge. You look back and notice the quality has changed and at some stage you start looking at your collection and you wonder about what to do next. The work is done but should you keep going?
A photographic project can stay with you for a short period, a year, a decade or your whole life. There is no rule when to finish, you make the decision or you never finish at all.
The end of a project can lead you into a new one.
You should start a new project this year. In 12 month time and 5000 photos later you know it had a purpose.