The crops below show the performance of the Nikon Coolpix S610 next to the same ISO for the Fuji Finepix F100fd. These cameras have a large sensitivity range, starting at ISO 100 and going up to ISO 3200 at full resolution. The F100 also has higher sensitivities at reduced resolutions. This required a scene with very low-lighting which made taking the shots an exercise in tricking the cameras. As can be seen below, such low-lit scene could not always be properly exposed at all ISO settings. Outside of camera testing, this is not really an issue as you only need to get the right exposure at a reasonable ISO.

All crops below are 100% from their respective camera taken at the highest image quality setting available. Aside for the scene-mode used for the Fuji's ISO 100 shot, all other settings were left on automatic or on their default values. These crops help determine which ISO settings can be acceptably used on these cameras. As noise increases, most cameras compensate with noise reduction which introduces softness. The point at which a print become unacceptably noisy is a matter of personal taste.

Nikon Coolpix S610

Fuji Finepix F100fd