I have done this experiment to prove that an old Digital camera like the Canon S45 with a very good sensor for the time (in 2002) is able to take pictures at higher ISO than it was supposed to do. Especially if you compare it with the output of the high ISO on the new CANON models.

You have to keep in mind that most of the pictures that you will print will usually be in 4x6 or 5x7 size, this means that a 4 megapixels is large enough to cover the quality of print for this size.

Most new cameras from Canon bring High sensibility and high megapixels but they fail to give you RAW capability.

Example:
- for a picture at : 1/15 F2.8 ISO400, if you want to go to ISO800, you double the speed of exposition (-1 EV) : 1/15 x 2 = 1/30 --> 1/30 F2.8 ISO400, this will give you the correct exposure for the ISO 800 after that in your Raw edition software (+1EV).

- You can do the same by only adjusting the EV and let the camera calculate the correct exposure, you do the same again in your Raw edition software.

All the pictures have been passed through one Post Process software: Raw Shooter 2006, and i have saved the pictures in JPEG High quality.

I know that a lot of other softwares are able to remove noise better than Raw Shooter, but i wanted a fast way to only adjust the exposure and remove a little bit of noise.