Dynamic Range in Film Photography

A Complete Guide to Your Film’s Defining Characteristic

13 min read by Dmitri.
Published on . Updated on .
7 stops of estimated dynamic range illustrated with Film Ferrania P30.

Understanding your film’s dynamic range will help you improve the quality of your images by avoiding loss of detail and mastering the contrast. You will also be able to make new deliberate creative choices and know exactly what to look for in your emulsion besides grain type and colour.

Dynamic range in simple terms.

Imagine leaving a dark room on a bright sunny day: it’s almost too painful to see anything in the first few seconds outside. But once your eyes finally adjust to the glaring sunshine, going back inside is another hassle: the room that you could previously navigate with ease appears pitch black, and you stub your toe.

This annoying limitation of human vision is due to its finite dynamic range. Our eyes’ retinas have a limited range of light intensities they can perceive at once — beyond which everything appears either pure white or pitch black.

This range could be shifted with the help of the pupil that acts as an aperture (plus a few other tricks). This is how we can eventually adapt to the bright sunshine out of the dark room. But the range itself is constant: we can not simultaneously see detail in the dark and in the bright light.

Photographic film has the same limitation: beyond a certain range of light intensities, it will render everything pure white or pitch black. Our cameras let us shift this range to work in brighter or darker scenes with the help of apertures, shutter speeds, and lens filters. Though shiftable, the range itself remains constant and can only be altered with your emulsion choice and the way you develop it.

Figure 1. The dynamic range of a hypothetical negative film emulsion.

Dynamic range in film photography.

Dynamic range is a blanket term, defined as “the ratio between the largest and smallest values that a certain quantity can assume. It can be measured in decibels (for sound) or stops (for light). Dynamic range is also sometimes referred to as tonal range.