What is ISO? How does it affect your camera?

ISO controls the amount of light your camera lets in, so it tells you how light or dark your photos will be. Low values, such as ISO 100, are best for a sunny outdoor shoot. For shooting at night or indoors with dim lighting use an ISO of 1600 or higher. As you increase your ISO number, your photos will grow progressively brighter. For that reason, ISO can help you capture images in darker environments, or be more flexible about your aperture and shutter speed settings.

High/ Low ISO

The lower the ISO number, the more light is needed to properly expose the image. The higher the ISO number, the less light is needed. ISO 200 requires much more light than ISO 6400.

What effect can a High/ Low ISO have on your camera?

The higher the ISO number, the higher your camera’s sensitivity, and the less light you need to take a picture. The trade-off is that higher ISOs can lead to degraded image quality and cause your photos to be grainy or “noisy.” At the lowest (base) ISO setting, your images will have the least amount of noise and the highest dynamic range, giving you the most flexibility in post-processing.

What is meant by visual noise?

Noise in photography can be defined as a random variation in the image signal. Noise can be caused by a number of factors, including poor lighting conditions, high ISO settings, long exposure times, and heat.

When might you want to use a high ISO?

High ISO is generally well suited to low-light situations, especially when a fast shutter speed or a narrow lens aperture is essential to achieving a creative goal. Sometimes a little noise can actually even add character to your images.

My photos

The photos on the right were taken at an ISO of 6400 and shutter speed of 1/20 of a second. This makes the photo look brighter and less textured whereas the photos on the left were taken at an ISO of 100 at 1/20 of a second which gives the photos more dimension if in a lighter room.