The test camera is mainly tested for resolution and color reproduction, illumination, and backlight compensation. The next step is to measure the distortion, power consumption, and minimum operating voltage of the surveillance camera. The following steps are first used to measure sharpness, color reproduction, and illumination and backlight compensation. Let me introduce it first.
1 . Measurement of sharpness: When multiple surveillance cameras are used for testing, the same lens should be used (it is recommended to use fixed focus and two variable lenses). The center circle of the test card appears on the left and right edges of the monitor screen. Clear and accurate Count a total of 10 vertical lines and 10 horizontal lines for the given tick marks. Represents vertical resolution and horizontal resolution, respectively, and the corresponding set has given the number of lines. For example, the vertical 350 lines are horizontal 800 lines. At this time, it is best to use a black-and-white monitor. The test can focus on distant objects or focus on the edge. It is best to use both, and you can see the differences in this camera (for far and near convergence).
2 . Monitoring camera color reproduction test: Test this parameter should choose a good color monitor. First, observe characters and costumes from a distance to see whether there is color distortion or not. Compare the objects with vivid colors. Look at the sensitivity of the surveillance cameras. Before taking the color pictures on the surveillance cameras, look at the pictures clearly, too light or too thick. Take color pictures of moving objects to see if there are color trails, delays, blurs, etc. The test conditions such that the maximum illuminance of the camera should be measured under 50+10V illuminance at 50V, that is, 10V on the basis of the most illuminance of each surveillance camera, and the aperture should maintain the closest state.
3 . Illumination: The surveillance camera is placed in a darkroom. Before and after the darkroom, there is an active 220V self-firing lamp. A voltage regulator is provided at the front and back. The regulator adjusts the voltage generation to adjust the darkness of the dark room lamp. The voltage can be adjusted from 0V to 250V. The indoor illumination can also be adjusted from the darkest to the brightest. When the camera's aperture is open to the maximum, the next minimum illuminance value is recorded during the test (the active light regulator is dimmed to a position that cannot be seen in the dark interior). Hit the minimum and then record the next minimum illuminance value.
4 . Surveillance Camera Backlight Compensation: There are two methods to test this parameter: one is in the dark room, the front of the camera is turned on to adjust the light to the brightest, and then put a picture or text under the lamp, the surveillance camera welcome Optical camera, to see whether the image and text can be seen, the picture is not harsh glare, and adjust the AL, AX pull switch to see if there is any change, which effect is best. The other is to take the camera out of the window when the sun is shining. At this time, you can see if the image and text are clear.
5. Surveillance Camera Distortion: Look at the distortion of the surveillance camera. Place the test card at the front of the camera so that the entire sphere appears on the screen. See if the sphere has an ellipse. Move the camera forward to see if the center of the circle is magnified. Then test the edge, angle, and distance. The box has no arc distortion.
6 . Surveillance camera power consumption: minimum operating voltage, use a multimeter to measure current, use a small voltage regulator to adjust the voltage
In the security system, the image generation is currently mainly from the CCD camera. The CCD is an abbreviation for the charge coupled device (charge coupled deice). It can convert light into charge and store and transfer the charge, and can also take out the stored charge. Because the voltage changes, it is an ideal camera component. The CCD camera that is composed of the CCD camera is widely used due to its small size, light weight, the influence of the magnetic field, and the characteristics of shock resistance and impact.