How to Use Extended Low ISO for Cleaner Photos
Does your camera have an Extended ISO function? Using it can help you produce less noisy images than the base native ISO of your camera. Here’s a 4-minute video tutorial explaining this.
The extended ISO setting on your camera may appear as 50, L, or something similar. This is different from normal ISO settings in that rather than modifying the actual sensor light sensitivity, the camera overexposes by one stop, and then pulls the exposure back for you.
This effect could be simulated by using the ETTR technique, or “Expose To The Right”. This is achieved by setting your camera to the base ISO and intentionally overexposing by 1 EV, and then fixing the exposure in post. The only difference is that the preview in-camera would appear overexposed.
The result of using this technique is very little noise and a high degree of detail, especially in the shadows. However, you will be losing a full stop of dynamic range in your highlights. If you’re careful not to clip your highlights too much, this can be a very useful technique to get the cleanest image possible.
Check the video at the top for the full rundown and Northrup’s comparisons between ISO 50 and ISO 100. You can find more of his videos at his YouTube channel.
(via Tony Northrup via Shutterbug)
