Take your best shot

What is RAW?

By Adrian Toon, director of a2n.

Simply put, RAW is the output from the camera sensor when you take an image.

It is a record of each pixel output and it is similar to what a film camera took as a ‘negative’, if you like an original image with all the captured data. Unlike the film negative, which was captured on celluloid and always in a common negative format, each make of camera’s raw data output differs, so it is not a uniform format. So why do we use it?

All digital cameras take pictures in RAW, the sensor’s output, and the camera’s software converts it to an image in a common JPG format.

Unfortunately, not all cameras will output the RAW file. JPG is what is known as a compressed image format and the user can often select the data size of the image – the higher the compression the smaller the file size and the poorer quality of the image.

Even at JPG’s lowest compression (largest data file size), a JPG image will lose much of the original data in the RAW file. This common output makes the image easy to use on all other devices and software applications.

Professional photographers prefer to work with the RAW image, rather than let the camera’s software make assumptions of what data to use in the final image.

Many good quality image processing software packages, such as Photoshop, have a RAW format processor, which is often updated to suit new cameras being brought onto the market.

If you are going to take image capture seriously, the RAW format gives the photographer a great deal of control over what data can be used to create stunning images with colour depth and clarity. Once processed by the photographer the final image can then be output into any file format, including JPG, which is suitable for its destined use.