What is ISO? How does it affect your camera?
ISO controls the amount of light your camera lets in, and therefore how dark or light your photos will be and how sensitive your camera sensor is to light. 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.”
What does a high ISO / low ISO mean? What effect can this have on your photos? What is meant by visual noise?
The higher the ISO number, the less light is needed and the more grainy a image is. The lower the ISO number, the more light is needed to properly expose the image, this makes the image smother and more detailed but is darker. 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. The higher the ISO, the more amplification your sensor needs, and the more noise you will see in your image.
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. Using a higher ISO setting for hand-held street photography at night allows one to use fast shutter speeds to create bright, sharp images.
Exploring the effects of ISO
As you can see in these photos, there is a clear difference between which image is lighter and darker, this is determined by the amount of ISO used. In the top photo I used a lower ISO, in which made the photo a lot darker and more accurate to how light it really was in the studio. In the bottom photo I used a moderately high ISO, this is because I didn’t want the image to be too bright but still wanted to add more detail and to see what was in the actual image. Also if you look close enough you can see the grain that I mentioned in the blog. I could prevent this to make a more clearer image by decreasing the shutter speed, but with this I would have to keep the camera steady to reduce blur.
Final images:
