The Nikon Coolpix S9100 offers a light sensitivity range starting out at a user selectable ISO160 and topping out at ISO3200. We also get both Auto ISO and a user selectable fixed ISO range setting, so users can limit how high the camera automatically 'strays' to preserve picture quality. Let's see how the S9100 gets on with our standard test set up, shot using a tripod, available light at the highest JPEG resolution and utilising auto white balance.
The lowest setting on the S9100 is ISO160, coincidentally also the option the camera itself chose when we tried both its Auto ISO and the Fixed Range ISO settings. As we'd expect there's no noise visible anywhere in the image
Up a notch at ISO200 and all is still well with the S9100's performance; again no image noise to report
We're at ISO400, the setting at which noise begins to creep into shadow areas on lesser compacts. But again we have a clean bill of health from the S9100. If we scrutinise the image very closely it's marginally softer than at ISO200
At ISO800 there's a subtle softening of overall detail which has again kept any instance of image noise at bay - but this really is nit picking as viewing the full frame you'd be hard pressed to notice any difference at all between this and the lower settings
At ISO1600 shadow detail is beginning to take on a speckled appearance - but only if you're really looking closely
The top setting of ISO3200 and there's a more obvious smoothing effect as well as a slight colour shift compared with the previous images. Overall though the S9100 has delivered a very respectable ISO performance for a sub £300 camera.