THIS MONTH: IN- CAMERA PROCESING
What options are available for adjusting the look of your photos?
To convert this image, the raw data needs to be decoded
QUITE a lot of things happen very quickly when you press the shutter release button
on your camera. The light reflected off the subject is captured by the lens and fed to the image sensor, where it’s recorded as an analogue electrical signal then turned into digital data by the analogue/digital converter.
All of this typically happens in a fraction of a second, but it’s really just the start of the process of creating an image. Before the file ends up being temporarily stored in the camera’s buffer prior to being written to the memory card, the massive amount of data created for each image you shoot has to be crunched. Digital processing that’s carried out at this stage includes adjustment of the white balance, colours and contrast, along with lens corrections, noise reduction and sharpening. How – or rather when – these adjustments are applied depends on the file format selected on the camera. In the case of JPEGs or TIFFs, they’re applied to the image before it’s finally compressed to create a smaller file size (in the case of a JPEG) and saved to the memory card. If you’re recording images as raw files, the processing data is saved as part of the file but not applied. At this stage, a raw file is not an image at all: rather it’s a data file that contains the raw binary code from the camera’s image sensor. To convert this information into a viewable image format such as a JPEG, the raw data first needs to be decoded. This is normally done using raw processing