On to the Photolife:
I'm a big proponent of documenting everything when taking pictures. It's kind of like when you're documenting your life including the prices of a gallon of gas or a loaf of bread the year you were born or telling stories about your dog's penchant for climbing trees (my mother had a dog that did that) or your favorite shoes in the summer. I love those sorts of details. Here's a picture that my niece took at a family get together.
I love all the details: the darkness of the foot imprints (they've obviously been well worn), the size differences (a nephew's and a niece's), that both shoes are Rainbows (an incredibly comfortable flip-flop that one niece swears by--in SC they know their flip-flops), etc.
Application to writing? It's important to give details of things that may seem trivial. It adds authenticity.