Non-animated lucid dreaming

For over a year now i have been having incredibly vivid lucid dreams, however I am not sure if they are actually dreams. They all are stationary, like looking at a very detailed 3D picture, and only last about 5 seconds usually early in the morning. I can be slightly awake and "make" one of them happen, however the picture that comes out is always something ive never seen before, and i cannot control what it will turn out to be. My question is how to make these last longer, what they are exactly they are, and if it is possible to control them.