Ansel Adams' books on the Camera, Lens, and Darkroom were my advanced starting point, Basic Photo One.
Learning to see is a joy, and anyone can join in. I think of light energy, photons, as a power and energy, to gather up with a camera. Understanding the possibilities of slicing up the electromagnetic spectrum will give a new way of understanding light for an artist. NASA has really developed this concept with deep space observation. Thinking, and using multiple wavelengths gives new insight and understanding. What was once considered "Fog" is now a new chance to see an object. I like to think beyond the red, blue, green spectrum, and embrace all of the light energy I can record.
All photography is Mixed Media Art. The possibilities are endless. Understanding the journey of a single photon can be artistically rewarding.