Dynamic Range and ISOs

The DigitalCameraInfo.com review of F30 has a chart on F30 Dynamic Range over ISOs...

http://www.digitalcamerainfo.com/... .../Testing--Performance.htm

It is interesting to note that at High Quality (0.1), F30 has a dynamic range of 6.8. It stays well as ISO200 with 6.6, but begins to drops at increasing rate when ISO is increased, reading from the chart, approximately 6.1 at ISO 400, 5.4 at ISO800, 4.8 at ISO1600, and 3.9 at ISO3200.

What I learned:

1. Dynamic range decreases with increasing ISO.

From ISO 100 to ISO3200 the drop is 3EV. From 400 to 3200 is 3EV. From 800 to 3200 is 1.5EV and From 1600 to 3200 is about .9 EV.

2. If the drop from 1600 to 3200 is .9EV loss of dynamic range and 1600 to 3200 is 1 EV of sensitivity. It makes sense to say that using 1600 with -1EV underexposure is about the same as using ISO3200.

3. Looking at the Dynamic Range of other Camera over the ISOs, F30 performed quite well. For example: Nikon D80, reading from the Chart,

Nikon D80 7.5 at 100, 6.8 at 200, 5.8 at 400, 6 at 800, 4.8 at 1600, 3.5 at 3200.
FinePix F30 6.8 6.6 6.1 5.4 4.8 , 3.9

But this does not mean F30 is as good as D80 as there are factors to picture quality.