What's film made of?

Traditional photography mixes creativity and science - early photography was developed by chemists.

So, let’s start at the VERY beginning and look at what film is made of and papers too. 

You don’t need to know how film and photographic paper is made in order to use it, but a little insight will maybe give you a better understanding and help if you decide that you would like to sell your work in the future.  An awareness of film and paper will help you know how precious your photographs are…

Think of it as a sandwich cake recipe and the icing on your cake!

The icing part is called an emulsion which is made up of Silver salts and gelatin - similar to what makes jelly thicken.   Top to bottom the layers are anti scratch layer, emulation, a mix of gelatin and silver halides the film base and an anti halation layer.

Light sensitive Silver salts, otherwise know as Silver halide crystals mixed together in a high grade gelatin to make an emulsion that is used to coat the paper or film.  On exposure to light - in a camera or darkroom, the crystals react turning into silver and forming the image.  

Depending on what size film you use and how bit you enlarge your negative - either on screen or on paper - you may be able to see the tiny grains of silver halide.  When you focus your enlarger in the darkroom, you focus on the grains of silver halide and not the actual subject of the photograph.  

The illustration below will help you visualise the roll of film that you are putting through your camera.

Two questions I am often asked...

Colour film is made in the same way, but with a more complicated mix of emulsions. Instead of one layer of emulsion there are layers of blue sensitive emulsion, a yellow filter layer, a green sensitive layer then a red filter layer and a red sensitive cyan layer. 

Usually the emulsion side is uppermost and closest to the lens in your camera. This is how your spool film will arrive from the factory. 

However, you can now buy film, usually 35mm, that has been wound on to the spool the other way.  Taking photographs using this film is referred to as the Redscale technique. 

This makes a filter effect, filtering out the bands of light (some colours) leaving a red tone.  Think rich, red sunsets - filled with beautiful red and yellow hues across each photograph.

I hope you enjoyed reading this. Thanks for dropping by.  Julie