Since I don’t own a 360, I am unsure if cameras are placed differently on that platform. But for the One, other threads and other sites deal with your question already.
Not completely true mate; a road driven during a Championship Race or Career Road Trip, won’t “detect” the camera stationed there not trigger it. One of the notorious cameras not showing up is the one from Nice leading towards Sisteron; somewhere between those cities is a little triple hairpin dirtroad that is usually only used on 1 Race Event but contains a camera.
/edit: lol, Swooshain posted almost exactly the same
You can “drive” a road during a race or roadtrip and it won’t activate (and therefore add to the map) a camera. I had the same issue which I thought was a sync issue until I actually went looking for them. The three most likely cuplrits are the one at the bottom-right of the map east of Castelletto; the one about halfway up the map from Castelletto to Montellino on a dirt road at the very eastern side of the map; and one in a small looping road in the north-west corner of Nice, near the enterance to the hill-climb road.
B Wald, why didn’t you tell me you were missing a camera, I could have helped you find it?!
Have you guys looked in Nice? There was one I was missing and found last. It’s hard to find because it’s hidden because it’s super close to the Nice-Massena Horizon Hub and few races go through it. The game rarely takes you down the road, I rarely drove down the road on my own, and when you do it may be leaving the Horizon Hub and not going fast enough to trigger the camera.
That was the one that was the toughest for me.
Also, if you see the camera and drive through it but you are in a Road Trip, Race, Head to Head race, or any other event EXCEPT free roam, it will appear on your map but it does not count as a discovery.
There is a small 2 camera one in Nice in a weird place and if you don’t go through it the right way it doesn’t activate. It’s one of the ones where you have to go though both cameras to activate it. Maybe that’s the one you’re missing?