ISO seems to be a much more complicated topic than it needs to be really. I see so many questions about ISO posted online from confused new camera owners that it makes me wonder when it got so complex. But it’s really not that difficult to grasp, really, when it’s broken down and explained.
In this video, photographer Dave McKeegan walks us through ISO, explains the terms and elaborates on some of the tech so that you can understand the differences between base ISO, native ISO and extended ISO. He also explains what the hell dual native ISO is, how it works and how it can benefit you as a creative.
Dave goes quite in-depth and geeky in the video, and it’s well worth a watch if you want to understand how ISO works and how it’s not usually the same as just ramping up or down the exposure slider in Lightroom.
In short, though, the base ISO of your camera is the cleanest possible signal your camera can produce without requiring any amplification whatsoever. Native ISO is the range of values available when the signal from the sensor is amplified through an analogue circuit before it’s sent to the camera’s processor. Extended ISO is a range of values available after the signal has been processed by the sensor using digital amplification. Extended ISO is more like dragging the sliders in Lightroom.
And dual ISO is where camera systems such as those from Blackmagic, Sony and Panasonic utilise two separate analogue amplification circuits for different ISO ranges before the signal reaches the processor to maximise the signal to noise ratio and improve overall image quality. You’re still going to get some noise at that higher native ISO, but it’s going to be much less than if the original signal were digitally boosted.
Did this video teach you something you didn’t already know or has it just left you more confused?