Science of Photography

– By Raksita Rajagopal, age 15

Have you ever wondered whether there’s a science behind a single photograph? Because there is! There is a reaction behind every click. Scroll ahead if you’d like to know more!

The science of photography covers all aspects of science. Physics, chemistry, you name it! It starts from the lens and continues until the picture develops. Let’s see the process behind a single click.

The science of photography includes chemistry, physics, and sometimes maths too! This includes the angle of the camera, the flash, and also the lens and the physical operations of the camera.

One of the main prerequisites of photography is having a camera. In the camera, the main part is the lens. The functioning of the lens itself is based on physics. It was invented between the 11th and 13th centuries and works on principles of reflection, magnification, and light.
This also applies to the click or focus options. The camera identifies all the light rays and adjusts according to the color and the distance of the subject.

This subject is in sharp focus while the distant background is not.

Focus is the tendency of light rays to reach the same place on the image sensor or film, independent of where they pass through the lens. For clear pictures, the focus is adjusted for a longer distance, because rays reach different parts of the lens at different angles, depending on the distance of the subject. In modern photography, focusing is often accomplished automatically.

Many scientific thoughts, right?

Yes, science plays an important role in photography. Photography isn’t only about taking photos and developing them!

Motion blur

Motion blur is caused when either the camera or the subject moves during the exposure. This causes a distinctive streaky appearance to the moving object or the entire picture (in the case of camera shake).

If you know how to apply these techniques to photography, you could take a beautiful photo!

Law of reciprocity:

The law of reciprocity describes how light intensity and duration trade-off to make an exposure—it defines the relationship between shutter speed and aperture, for a given total exposure. Changes to any of these elements are often measured in units known as ‘stops’; a stop is equal to a factor of two.

Halving the amount of light exposing the film can be achieved either by:

  1. Closing the aperture by one-stop
  2. Decreasing the shutter time (increasing the shutter speed) by one-stop
  3. Cutting the scene lighting by half

That’s a lot of science! Discussing the science behind photography could be a book on its own.

As we say, A picture paints a thousand words.

Until next time,


Raksita Rajagopal.

Leave a Reply

Your email address will not be published. Required fields are marked *