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The light and shadow magician has the function of CCD dead point test, which is explained in detail.

turn:

The bad point is that the CCD produces a dead spot that is always bright or dark when imaging, and its position is fixed. The root cause is due to the limitation of the current technology level of CCD and the low yield. Noise is the "noise" randomly generated by CCD when it is exposed to light, and its position is not fixed, and it will increase with the increase of environmental temperature. Strictly speaking, noise is inevitable, but most of it is ignored because we can't see it with the naked eye.

Specific methods for testing bad noise:

1. Because the noise activity is closely related to the ambient temperature of CCD, it generally reaches a relatively stable state after 1 to 3 minutes of starting shooting, so we need to take test photos during this period.

2. Closing date (many friends don't pay attention to this step)

3. Bad noise is related to shutter, aperture, ISO and other parameters. We set the parameters in the most commonly used state: the aperture F2.8, ISO1 and shutter are adjusted step by step from 1/6s to 1s (even slower), provided that the camera is fully manual or at least equipped with S-file (shutter priority), the automatic file can only be used for non-manual machine.

4. Open this photo in the software and take the default standard (6,25) for testing. In 1/1s, the noise number of is regarded as "excellent", and less than 1 is regarded as "normal"; Under 1s, the number of noise points is still "excellent", and less than 1 is also "good".

5. Due to the limitation of the software, the "noise points" less than 25 need to be photographed many times. If the coordinates are consistent every time, it can be regarded as "quasi-bad points". As long as it is not in the central key position, it has little impact on imaging, so don't worry.

Everyone is concerned about "lumen"

if you are a beginner, it is recommended to buy S15, which is completely sufficient; If you are interested in camera shooting, you can buy S2hd, which has 72P high-definition camera shooting function. This software is very helpful for beginners to get started. END