Tuesday, 11. September 2007

Sensitivity

The fact that sensors are kept small, but get sectioned into more and therefore In order to compensate the lesser degree of sensitivity, the signal from the sensor needs to be amplified so that smaller “amounts of water” become visible. However, drops that were spilled or flooded appear as noise in the picture.

Please click on a picture for details.

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Complete picture, ISO 100

The following sections are extracted from pictures taken with cameras with a different number of megapixels. On every picture you’ll see the sections in the following order:

upper left: Fuji F31 fd w/6.3 megapixels, upper right: Olympus 725 SW w/7.1 megapixels

lower left: Canon 950 IS w/8 megapixels, lower right: Casio Exilim Z1200 w/12.1 megapixels

Please note that the cameras were randomly chosen. According to our experience they show a typical behaviour for the represented camera class. To make the displayed images believable we decided to mention the cameras we used but we do not want to criticize a single model or manufacturer but the pixel race in general.

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Picture center, ISO 100 Picture center, ISO 400

In “Picture center, ISO 100″, you can see that Olympus and Canon smooth out parts of the tree trunks, the path and the bushes to the left. The difference of the detail reproduction between the 6.3 and the 12.1 megapixel camera is not very significant. It is obvious that Casio smoothes out as well and sharpens contours that are easy for it to recognize. Furthermore, additional errors become visible because of jpeg compression, e.g. in the form of white dots (visible in the bushes).

In “Picture center. ISO 400″ it is obvious that Fuji F31 fd is the camera that features the highest detail reproduction and has the smallest amount of megapixels in our comparison. The others seem blurry.

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Picture edge, ISO 100 Picture edge, ISO 400

In the crops of “Picture edge, ISO 100″, you can’t see many details in the Olympus image and just moderate details in the 8 and 12.1 megapixel cameras. In the examples of the last ones, the grass blades seem to melt into each other. Single blades and little stones are still recognizable with the Fuji F31fd.

It is obvious in “Picture edge, ISO 400″ : the 6.3 megapixel camera shows the most details.