Thursday, October 7, 2010

ISO ratings and memory card capacity

If you want to maximise the number of images that you can fit on a memory card, you should shoot at a lower ISO setting. As you increase ISO ratings your images will feature more image noise. Since image noise is seen as ‘detail’ it cannot be compressed – therefore each file will be larger, meaning fewer images on a memory card. If the situation dictates that you need to shoot at high ISO settings then you should always do so. However, if you don’t need the benefits of high ISO shooting, make sure that you set a lower ISO speed in order to maximise how many images you will be able to fit on to your memory card.


  1. Interesting fact. One other thing about about ISO which many might not know, when you do need to use high ISO keep the histogram to the high side as noise mostly develops in the dark shadowy areas. This is also because most of the information is reserved to the right side of the histogram.

  2. If you can use lower ISO and lower the F. Or bigger F with longer exposure.

    With higher ISO you will get a lot of noise.

  3. Noise in an image appears first in shadow areas. This is because these areas have a lower signal (less light) compared to the inherent digital noise in an electrical system. To reduce the noise you see in images, especially at high ISOs, you need to capture as much light as possible. To do this, simply expose to the right – i.e. tend towards overexposure without going far enough to blow the highlights. This will maximise your signal-to-noise ratio and minimise any noise you may see in your images.