Here are photo micrographs of actual color films.

One compares film to a human hair, and the other shows film before and after processing.

In the before and after process photos, you can see the silver grains in one and not in the other, and you can also see the change in the layers.

Again, I am indebted to my friend, Dr. Bruce Kahn for permission to use these photos.

You can see from the size of the hair in comparison to the thickness of the film layers why I have likened photo engineering to designing a biological system, as we are working on the scale of cellular structures or smaller, when we build and examine film.