Light not only illuminates a scene but also determines its color. White balance is the camera's adjustment for the color temperature of light, measured in Kelvin (K). Lower Kelvin values produce warmer (more orange) tones — tungsten lighting sits around 3,200 K — while higher values produce cooler (more blue) tones, with daylight near 5,500 K and overcast skies around 6,500 K. Cameras offer automatic white balance (AWB), preset modes for common conditions, and custom white balance calibrated using a neutral reference such as an 18% gray card.
The choice of file format dramatically affects how much flexibility the photographer retains in post-processing. RAW files contain unprocessed sensor data, are large (typically 20–100 MB), and allow extensive editing, including white balance adjustment after the fact. JPEG files are processed and compressed inside the camera, producing smaller files (2–15 MB) but offering less room to recover highlights, shadows, or color shifts. Many photographers follow the rule "shoot RAW" to preserve the maximum data from every exposure.
Beyond color temperature, the direction and quality of light profoundly shape an image. Front light flattens a subject; side light reveals texture and depth; back light can produce silhouettes or rim light that separates the subject from the background. The golden hour, just after sunrise or before sunset, offers warm directional light; the blue hour, just before sunrise or after sunset, provides cool ambient tones; and harsh midday sun creates strong shadows that are usually unflattering, making open shade a better choice on bright days. The inverse square law reminds us that light intensity falls rapidly with distance — light close to a subject is bright but falls off dramatically, while light placed farther away produces a more even but dimmer result.