Checking the matrix for dead pixels is one of the most important stages of testing a camera when buying. Having mastered a number of simple steps, you can avoid unpleasant multi-colored dots in photographs and be sure that the matrix on your camera is in good working order.
Instructions
Step 1
Set the manual shooting mode (M).
Step 2
We set the ISO value to 100 or lower, turn on the manual focus (MF).
Step 3
We choose the maximum image quality.
Step 4
If Noise Reduction is on, turn it off.
Step 5
We take about 10 shots to "warm up" the matrix.
Step 6
We close the lens with a cap and take a photo, setting the shutter speed to 5-10 seconds. If there is no cover, then we photograph some soft surface, resting the lens on it. The main thing is to ensure complete blackout.
Step 7
At high magnification, we carefully examine the image, step by step, without missing any areas. Ideally, you will end up with a completely black photo.
However, on a black background, multi-colored dots may be visible - faulty pixels. There are two types of such pixels: broken (cold) and hot.
Cold pixels are not working. They are noticeable first of all, as they stand out brightly in the dark areas of the photo. Most often they are white, but they can also be black.
Hot pixels appear when the sensor heats up, they can be red, blue or green. The matrix heats up at high ISO values, long exposure times, or simply due to high ambient temperatures. A few broken or hot pixels are considered normal, but if their number is more than 4-5, it is better to refuse to buy a camera. Even if the pixels are not very visible in the photographs, they may indicate a problem with the sensor. In this case, their number will increase over time.
