how the picture changes depending of the exposition and/or ISO number.

1.

 *this pictures were took with a diferent camera, a reflex, so the exposition number appears in a different way: in the semi refles i was using was marked from 0.0 to + or - exposition number, in this reflex one it marked as 1/...

2.

 1: because I took this picture with the light against the subject, it looks darker than the background. (exposition1/100, ISO 100)

2: as the first shot left the subject really dark I did it again with the same exposition number but the ISO in 200.
as we can see, when we put up the ISO number the shot gets brighter.

3.

 3: exposition 1/60 (more open than 1/100)
ISO 400

4:exposition 1/40  ISO400

5: exposition 1/25 ISO400

6: exposition 1/15 ISO400

7: exposition 1/10 ISO400

8: exposition 1/6 ISO400

The difference between use a higher ISO

4.

 number and a longer exposition time is that the higher ISO makes the whole shot brighter automatically, but the longer exposure time takes actually longer taking the ambient light and showing it on the image. In the pictures here posted you can appreciate  how the picture changes through changing the settings of the camera.

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