Assuming you are a digital camera user you may not have ever shot film so you possibly don’t know what “ISO” numbers are or for that matter be interested as it sounds a bit technical. However, if you want to be a little more creative with your camera it is worth knowing a little bit more about them.
The ISO number is simply the light sensitivity of either a film or your digital sensor. (ISO = International Standard Organisation and the reason why this is standard is so we get consistency when we photograph)
Low ISO number such as 50, are generally used for very bright lighting conditions. High ISO number such as: 3200 are used for low lighting conditions or to capture fast action. Some digital compacts will give you the option to change these settings manually it is worth investigating if you can with your camera.
The amount light entering our camera is controlled by the shutter speed and the lens aperture more on these in later blog articles, but briefly if we are hand holding our camera then we need a fairly fast shutter speed to stop “camera shake” if we move even a small amount while we are capturing the image it is not going to be a very clear. So as a general rule we say we need a stutter speed of at least 1/125 of a second and most cameras in automatic mode will go to this or higher.
I often get asked why someone has got what would be great image shot in low light say candle light in a restaurant but it is fuzzy or unsharp without flash, and with flash is clear but unpleasant because the ambiance of the scene has been totally removed by the flash. The reason is down to their cameras automatic settings increasing the light sensitivity of the sensor to allow more light in, but the shutter speed also going below 1/125 in order to do this, resulting in a blurred image. Flash typically works at 1/60 second which lets more light into the camera but also generates even more light due to the flash with it’s burst of light being very much faster than the shutter speed thereby freezing a point in time whilst the shutter is open. So lets say we want our ambient candle lit shot we can achieve this by changing our ISO setting to the highest we can and increasing the shutter speed or keeping the camera and subject very still whilst we take the shot, this could mean resting the camera on to a flat stable surface or as with the image here a tripod was used.Labels: marc byram photo tips iso light sensitivity photography
I often get asked why someone has got what would be great image shot in low light say candle light in a restaurant but it is fuzzy or unsharp without flash, and with flash is clear but unpleasant because the ambiance of the scene has been totally removed by the flash. The reason is down to their cameras automatic settings increasing the light sensitivity of the sensor to allow more light in, but the shutter speed also going below 1/125 in order to do this, resulting in a blurred image. Flash typically works at 1/60 second which lets more light into the camera but also generates even more light due to the flash with it’s burst of light being very much faster than the shutter speed thereby freezing a point in time whilst the shutter is open. So lets say we want our ambient candle lit shot we can achieve this by changing our ISO setting to the highest we can and increasing the shutter speed or keeping the camera and subject very still whilst we take the shot, this could mean resting the camera on to a flat stable surface or as with the image here a tripod was used.