Your web browser is out of date. Update your browser for more security, speed and the best experience on this site.
Find out more
ISO Speed

What is this ISO stuff?

And why it is important to us

Ever paused for thought when you "set the ISO" setting on your camera? Or chosen a film type by speed for Analogue photography. What does ISO actually mean?

ISO is the International Organisation for Standardization, based in Geneva. It is organised into  technical committees (groups of experts focusing on a specific subject), each given a number. Technical Committee 42 is dedicated to Photography.

It deals with some mundane stuff like dimensions but this is important too. It ensures that when you buy a tripod the thread fits your camera. It looks after perforations and widths for camera films too.

It also deals with the permanence of prints in collections, an area I have been active in for the last 20 years. We are now taking this expertise into museum storage too.

And of course ISO speed ratings for digital cameras, which is what set off this train of thought. The title is a bit of a mouthful "BS ISO 12232 Photography — Digital still cameras — Determination of exposure index, ISO speed ratings, standard output sensitivity, and recommended exposure index" and the latest version of this has just been released.

This could only happen through the work of technical experts from around the world, and RPS members play a significant part through our UK committee. For ISO 12232 we should recognise the contribution of Hani Muammar ASIS FRPS.

One aspect of our volunteering that perhaps goes unrecognised. Fancy joining the team?