RAW is a file format that stores uncompressed, unprocessed ‘raw’ data from a camera’s image sensor. For example, most digital cameras will attempt to compensate for white balance when writing an image to memory, but in RAW mode no such adjustments are made. Instead, the sensor data is saved with no in-camera processing, allowing the photographer maximum latitude in post-production.
Think of a RAW file as the digital equivalent of a photographic negative – in fact, RAW images are sometimes referred to as digital negatives, because they contain all of the necessary data to create an image once ‘developed’.
Reasons you should be shooting RAW
- You can’t trust your camera to make the best decisions. Camera makers have prioritized that when you take a picture, your camera will make onboard adjustments to make it look good. Algorithms, however, aren’t as intelligent as you are. In RAW, no onboard processing decisions are made: no white balance, no exposure, so sharpening, colour adjustment, nothing. The camera just tries to capture as much as possible and leaves all the important stuff up to you.
- More dynamic range. Dynamic range is the range of tonal values seen in your photograph. A higher dynamic range means your camera will record more detail in the shadows, at one end, and more detail in the highlights, at the other. This gets real important when you’re trying to shoot a high contrast scene: shadows disappearing into blackness and highlights blowing out into overexposure is no one’s idea of a good time. Shooting in RAW means you’ll get more image data at these extremes to work with later on.
- Post processing is non-destructive. That’s a fancy way of saying that whatever adjustments you make to your photo (contrast, brightness, saturation, even cropping and sharpening) the source file itself is never altered: they’re just adjustments, and you can alter or remove them as you like, even years later when you’re getting ready for your first big gallery showing.
Things to Note
- RAW images don’t appear as good as jpegs. You’ll notice the preview on your camera looks kind of flat and lifeless. This is normal: remember, RAW doesn’t process your picture, it captures the most image data possible, so that YOU can process it later, and capturing a high dynamic range makes things look flat. Don’t worry about it – all the magic happens in post.
- Less RAW files fit on your memory card. RAW files have more data, so they’re bigger, so you can fit less. But storage is cheap, and capacity is less important than the quality of your images and squeezing as much as you can from your camera.
- RAW is slower. You won’t be able to take as many rapid fire shots since RAW files take more time to write to the memory card.