Thread: YES DIGITAL CAMERAS CAN SEE UNDERGROUND EASY AND LIVE
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  #39  
Old 05-09-2020, 03:19 PM
liudengyuand liudengyuand is offline
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Since 940nm infrared light is used, why use a 940nm filter? In this case, the 940nm reflected light cannot be received, and the two LED lights are not perpendicular to the lens, but inclined at 30 degrees. What is its role?
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