I have a few of these cameras that appear to have been damaged by some form of cleaning the front lens. I have dismounted the lens and appears slightly opaque, enough to make the image as if moisture was present.
The size of these lens are quite small, nothing seen on eBay or Ali-Express, Its outer lens width is 9mm on a 3mm heigh shoulder. The body (screw thread) length is 5mm, diameter is 8mm, overall length is 9.5mm.
Alternatively if someone has some defective DB2 camera PCB (s), then I could take them off your hands for a couple of quid or so....
