Shooting in low-light situations provides many creative and photographic opportunities if you understand the mechanics of your camera. Real life does not always happen in perfect light, so understanding how to compensate for and anticipate all lighting situations will make you a well-rounded shooter. For the best results, understand the basic camera functions for shooting in manual settings and purchase the highest-quality camera and lens you can afford.
Manual Camera Settings
In order to capture as much light as possible when shooting in dark situations, you need to override the automatic settings on any camera. Most compact, point-and-shoot cameras have a manual option buried within the menu settings accessed through the LCD screen. If shooting in low-light situations will occur often and you are approaching photography as an advanced hobbyist or professional, a DSLR camera, or digital single-lens reflex, is your best option. A DSLR uses interchangeable lenses and highly responsive camera settings and both are necessary for challenging lighting situations. Low-light photography requires fast lenses, large aperture settings, slow shutter speeds and high ISO speeds in order to capture as much light as possible for your image.
Lowest Apeture Settings
The aperture settings control the amount of light allowed into your camera through the lens. A smaller aperture number, also referred to as a large aperture, will allow large amounts of light to enter the camera and render the image onto the film or image sensor that records the photograph. For example, a lens with an f/1.8 setting means that the opening in the lens is large and more light is coming into the camera. The lower the aperture of the lens, the "faster" the lens is, meaning it can function in low light very well. These fast lenses are also more expensive. Depending on the quality of the lens you purchase, a fast lens can cost several hundred to a few thousand dollars.
Slow Shutter Speeds
Slow shutter speeds work in coordination with the large aperture settings to allow light to enter the camera. The shutter speed refers to how fast the shutter curtain opens and closes when the shutter button is pressed to take an image. The shutter curtain covers the film or digital sensor and controls the amount of light that is captured on the sensor or film. This speed is measured in fractions of time, so when a camera uses a shutter speed of 250, it actually means 1/250th of a second. The lowest hand-held shutter speed, a point at which you should probably use a tripod to avoid blurry pictures, is 1/60th of a second. For low lighting, use as slow a shutter speed as possible, between 1/60th and 1/250 of a second or less. The shutter speed must be set in conjunction with the aperture in order to expose the image properly. If the shutter speed is too slow and the aperture is too large the image will be over-exposed or look "blown out."
The ISO setting on your camera indicates the light sensitivity of the film or image sensor. The ISO, formerly referred to as film speed, must also be set according to the amount of light present in the shooting situation. If the day is bright and sunny, a speed of 100 ISO should be sufficient. Yet, in a low-light situation, you will want at least a 400 ISO and possibly a 3200 ISO. The higher the ISO setting, the more light is captured on the sensor or film and the more "noise" that may be present in the image. Noise refers to the grainy texture that is often found in low-light photography. The amount of noise captured in a low-light image depends largely on the quality of the camera. A newer, higher-end camera will allow for low-light photography with high ISO settings that control the noise created by the image capture.