Adjust lens aperture and focus

Turn off the electronic shutter and backlight compensation on the high-definition digital camera.  Point the camera at the scene to be monitored.  And adjust the lens aperture and focus ring to optimize the image on the monitor. If the camera is used in a place with large changes in illumination.  It is best to connect an automatic aperture lens and set the electronic shutter switch (ELC) of the camera to OFF.  If a manual aperture is selected, the electronic shutter switch (ELC) of the camera should be set to At ON,

And when the application site is the brightest (the ambient light is the largest).  Open the lens aperture as wide as possible and still make the image the best. You can not make the image too white and overload.  Then the lens is adjusted.

Install the protective cover and attach the bracket. Due to the large aperture and relatively small depth of field range, the focus of the entire CCTV lens scene should be taken into account as much as possible. When the scene illumination decreases, the electronic shutter will be automatically adjusted to a slow speed, and with a larger aperture, the image can still be satisfied.

In the above adjustment process, if you do not pay attention to open the lens as wide as possible when the light is bright.  But close it relatively small, the electronic shutter of the security CCTV lens camera will automatically adjust to a low speed.  So it can still be on the monitor A better image is formed.  However, when the light becomes dark, because the aperture of the lens is relatively small.  And the electronic shutter is already at the slowest (1 / 50s), the imaging at this time may be dim.

Back focal length

It means that when a standard lens (standard C / CS interface lens) is installed, the subject can be imaged exactly on the target surface of the CCD image sensor. Generally, when the camera is shipped from the factory, the back focus is properly adjusted. Adjustment, therefore, in applications where fixed focus lenses are used.  It is generally not necessary to adjust the back focus of the camera.

In some applications, it may appear that the image is not clear when the lens focus ring is adjusted to the extreme position. At this time, you must first confirm whether the lens interface is correct. If the confirmation is correct, you need to adjust the back focus of the camera. According to experience, in most applications where CCTV lens cameras are equipped with electric zoom lenses.  It is often necessary to adjust the back focus of digital HD cameras.

The steps for back focus adjustment are as follows:

1. Mount the lens to the camera correctly.
2. Open the lens aperture as far as possible (the purpose is to reduce the depth of field to accurately find the imaging focus).
3. Push the lens to Tele state through ZoomIn, take a close-up of an object 10m away, and then adjust the focus to sharpen the close-up image.
4. Perform the zoom adjustment (ZoomOut) opposite to the previous step and pull the lens back to the Wide state. At this time, the screen becomes a panoramic image containing the above-mentioned close-up objects, but you cannot make focus adjustments at this time (note: if At this time, the image becomes blurred and the focus cannot be adjusted), but the next focus adjustment is prepared.
5. Loosen the hex screw that fixes the back focus adjustment ring on the front of the HD camera and rotate the back focus adjustment ring (for cameras without a back focus adjustment ring, directly rotate the lens to drive its built-in back focus ring) until Until the picture is clearest, then temporarily tighten the hexagon socket screws.
6. Push the lens back to the telephoto state and see if the close-up object just taken is still clear. If it is not clear, repeat steps a, b, and c above.
7. In the telephoto state, if the close-up object is clear, tighten the hexagon socket screw to adjust the aperture to an appropriate position.

At this point, the security HD CCTV camera and lens have been debugged

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