Nokia RM-627, Руководство по обслуживанию

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Camera module troubleshooting
Introduction to camera troubleshooting
Bad conditions often cause bad pictures. Therefore, the camera operation has to be checked in constant
conditions or by using a second, known-to-be-good Nokia device as reference. Image quality is hard to
measure quantitatively, and the difference between a good and a bad picture can be small. Some training
or experience may be needed to detect what is actually wrong.
When checking for possible errors in camera functionality, knowing what error is suspected significantly
helps the testing by narrowing down the amount of test cases. The following types of image quality problems
are common:
•
Dust (black spots)
•
Lack of sharpness
•
Bit errors
Camera troubleshooting
Taking and evaluating test pictures
When
taking
a test picture, remember the following:
•
Avoid bright fluorescent light, 50/60Hz electrical network or high artificial illumination levels
•
If the phone is hot, let it rest for a while before taking the picture
•
Make sure the optical system is clean
•
Use highest possible resolution
•
Make sure the light is sufficient (bright office lightning)
•
Do not take the picture towards a light source
•
Hold the phone as still as possible when taking the picture
•
If camera has auto focus: Pictures should be taken both at infinity ~>2m and at macro distance ~10-15 cm
in order to verify auto focus functionality
When
evaluating
a test picture, remember the following:
•
The center of the picture is sharper than the edges
•
The image may be blurred, though it does not show in the viewfinder
•
Analyse the picture from your PC monitor, full colour setting is recommended
•
If possible, compare with a picture of the same motive taken with a similar Nokia device
•
If camera has auto focus: Remember that the white focussing frame which appears when the camera
button is pressed halfway down, must turn green for auto focus lock. If the frame turns red, the camera
is not focussed!
RM-627
BB Troubleshooting and Manual Tuning Guide
Issue 1 COMPANY CONFIDENTIAL Page 3 – 33
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