Lens FAQ
Q: No reason for image output?
A. Check if the power supply is connected and the power supply voltage is enough.
B. BNC connector or video cable is not in poor contact.
C. Is the lens aperture open?
D. Whether the video or DC driven auto iris lens control wire is connected.
Q: What caused the image quality to be poor?
A. Is the lens fingerprint or dirty?
B. Is the aperture adjusted?
C. Poor contact of the video cable.
D. There is no problem with the electronic shutter or white balance settings.
E. Is the transmission distance too far?
F. Voltage is normal.
G. Is there a source of interference nearby?
H. When installing in an elevator, ensure that the elevator is insulated from interference.
I. Is the CS interface connected?
Q: What is backlight compensation?
Backlight compensation can provide ideal exposure of the target in front of very strong background light, regardless of whether the main target moves to the middle, up, down, left or right, or anywhere on the screen. An ordinary camera that does not have super dynamic characteristics only has a shutter speed of 1/60 seconds and F2.0 aperture selection, but a very bright background or a point light source behind a main target is inevitable and the camera will acquire The average of all recent rays determines the level of exposure. This is not a good idea because when the shutter speed increases, the aperture will be closed causing the main target to become too dark to be seen. To overcome this problem, a method called backlight compensation is widely used on most cameras through a weighted area theory. The image is first divided into 7 blocks or 6 areas (two areas are repeated). Each area can be independently weighted to calculate the exposure level. For example, the middle part can be added to the rest of the block by 9 times, so one is in the middle of the frame. The goal of the location can be seen very clearly, because the exposure is mainly calculated with reference to the light level in the middle area. However, there is a very big flaw. If the main target moves from mid-to-left to the top, bottom, left and right positions of the screen, the target will become very dark, because now it is not differentiated and has not been weighted.
Q: What is spherical aberration, distortion, color difference
Spherical aberration: a single-color conical beam emitted from an object point on the main shaft of the halo to the optical system. After being refracted by the optical series, if the rays of different aperture angles of the original beam cannot reach the same position on the spindle And even at the ideal image plane on the principal axis, a diffuse spot (commonly known as a fuzzy circle) is formed, and the imaging error of this optical system is called spherical aberration.
Distortion: The straight line outside the main axis in the object plane, which becomes a curve after imaging by the optical system, then the imaging error of this optical system is called distortion.
Chromatic aberration: A white light is emitted from the white object point to the optical system. After being refracted by the optical series, the red, orange, yellow, green, cyan, blue, and violet light components that make up the white light cannot converge at the same point. The white object point cannot form a white image point, and an imaging error that forms a color image is called a color difference.
Q: Why does the spherical aberration occur?
The imaging blur caused by coma is called halo. The oblique monochromatic conical beam emitted from an off-axis object point outside the axis to the optical system, after being refracted by this optical series, cannot form a clear image point, but only forms a diffuse light spot. When the image plane is moved to a certain position (sagittal image surface) after the current motion, the diffused spot becomes a short line s perpendicular to the sagittal plane of the optical system. When the image plane is moved back to the other position (the meridional image surface) at the present time, the diffused spot becomes a short line t perpendicular to the meridional plane of the optical system. An imaging plane with a minimal dispersion spot can be found between the meridional image surface and the sagittal image surface, and only an elliptical dispersion spot can be obtained at other positions. The imaging error of this optical system is called astigmatism. The size of the astigmatism is represented by the distance between the meridional focal line t and the sagittal focal line s.