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1.Testing of Color Reproducibility

 

A color monitor should be selected for testing this parameter. Firstly, observe people and clothing from a 

 

distance to see if there is any color distortion. Compare objects with bright colors and observe the sensitivity of the 

 

surveillance camera. Place a color brochure in front of the dome camera to see if the image is clearly outlined, 

 

whether it is too light or too dark. Then, capture moving colored objects to see if there is any color tailing, delay, blur, etc. 

 

The testing conditions are as follows: when the latest illumination of the camera is 50V, it should be measured at 5010V 

 

illumination, that is, ten volts should be added to the latest illumination of each monitoring camera, and the aperture 

 

should be kept in the closest state.

 

2. Measurement of clarity

 

When testing surveillance cameras, the same lens should be used (recommended to use fixed focus and two 

 

variable lenses), with the center circle of the test card appearing on the left and right sides of the monitor screen 

 

as the standard. Clearly and accurately count the 10 sets of vertical lines and 10 sets of horizontal lines that have 

 

been given. They respectively represent vertical clarity and horizontal clarity, and a corresponding set of lines has 

 

been given. If there are 350 lines vertically and 800 lines horizontally, it is best to use a black and white monitor 

 

at this time. During testing, it is possible to focus on distant objects or focus while measuring. It's best to use both, 

 

as you can see the difference between this camera (focusing on distance). 

 

3. Illumination

 

Place the surveillance camera in a dark room with active 220V self igniting lights in front and behind. Install a voltage 

 

regulator to adjust the brightness of the lights in the dark room. The voltage can be adjusted from 0V to 250V. Indoor 

 

lighting can also be adjusted from the darkest to the brightest. During testing, the camera aperture can be set to the 

 

maximum to record the lowest illuminance value (the active light can be dimmed with a voltage regulator to make it 

 

difficult to see the built-in image in the darkroom), and then the aperture can be set to the minimum to record the lowest 

 

illuminance value. The front and rear lights can also be adjusted to turn on and off separately.

 

4. Backlight compensation for surveillance cameras

 

There are two methods to test this parameter: one is to turn on the voltage regulating light on the front side of the 

 

camera in a dark room, set it to the brightest, and then place a picture or text below the light. Place the monitoring 

 

camera in front of the light to see if the image and text can be seen clearly and if the image is not dazzling. Adjust 

 

the AL and AX toggle switches to see if there is any change. Which one has the best effect. Another way is to shine 

 

the camera out of the window in sufficient sunlight, and see if the images and text can be seen clearly.

 

5. Power consumption of monitoring cameras

 

The minimum working voltage is measured using a multimeter to measure the current, and a small voltage regulator is 

 

used to adjust the voltage. In security systems, image generation mainly comes from CCD cameras. CCD is short for 

 

charge coupled device, which can convert light into charges and store and transfer them. It can also retrieve stored 

 

charges to change the voltage. 

 

Therefore, it is an ideal camera component, and CCD cameras composed of it are widely used due to their small size, 

 

light weight, immunity to magnetic fields, and resistance to earthquakes and impacts.

 

6. Distortion of surveillance cameras

 

To check for distortion in the surveillance camera, place the test card at the front of the camera so that the entire sphere 

 

appears on the screen. Check for ellipses in the sphere shape, move the camera forward to see if the center of the circle 

 

is enlarged, and then test for curved distortion in the edges, corners, and frames from a distance.