User Guide

Sensitivity

Camera module's sensitivity to light. In equivalent illumination conditions,

a less sensitive camera needs a longer exposure time to gather enough

light in forming a good image. Analogous to ISO speed in photographic

film.

Sharpness

Good quality images are 'sharp' or 'crisp', meaning that image details are

well visible in the picture. However, certain issues, such as non-idealities

in optics, cause image blurring, making objects in picture to appear 'soft'.

Each camera type typically has its own level of performance.

The effect of image taking conditions on image quality

Distance to target

The lens in the module is specified to operate satisfactorily from 30cm to infinite distance of scene objects.

In practice, the operation is such that close objects may be noticed to get more blurred when distance to

them is shortened from 40cm. Lack of sharpness will be first visible in full resolution (VGA) images. If observing

just the viewfinder, even very close objects may seem to appear sharp. This is normal behavior, do not change

the camera module.

Figure 65 Image blurred due to too close distance to target (5 cm)

Sharpness of picture edges

Lens performance degrades in image edges, and generally the image is sharpest in center part. Particularly

this applies to distant objects (> 1 meter). With near objects (about 5 cm – 30 cm) the lens behaves so that

center of the image may not be the sharpest point, instead maximum sharpness is approximately in half way

from center to edges. This phenomena can be seen particularly in images which have small details over the

whole image area, such as grass or similar. See the figure below. This is normal behavior, do not change the

camera module.

RM-135

Nokia Customer Care Camera Module Troubleshooting

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