Hi mates, thank you for your kind attention, I hope to find someone here who knows how AHD works and how many chances I have to solve this problem:
To help a friend broadcating his businness I bought for him some unexpensive Dahua Cameras, they are varifocal and suite perfectly what he's planning to do, I've bought also a video aquire tool from AHD to USB3 (4 channels, 720p). SInce the datasheet declares AHD output as possibility I bough with confidence.. an analog camera teorically is "stupid as possible" so the signal will not be manipulated, just the transmission change.. but actually not, Dahua found a way to worse its video signal AHD probably for not being convenient to buy without a CVI dahua recorder. Strange because TVI keeps the same quality of CVI.. and TVI is its main competitor Hikvision.. so why? I hope an hardware issue.
I've made these tests using a Dahua XVR, with PTZ menu I canched the output, and as you see even the OSD become unfocused. It looks an horizontal signal reflection on the right, but it can be a downscale of the lines, maybe, like it happens with 1080N for example. What do you think?
There is anything to put on cable (like a termination resistor) to solve this?
There is any way to convert externally a CVI to AHD? Do you have any documentation describing the 2 standards?
Thank you a lot for your considerations