jo-m
Camera Setup
After some prototype runs with a digital camera, now i want to pick a camera/lens for the permanent setup …
At 60m distance and catenary wires usually at 5.5m height, i have calculated i'll need a ~6° field of view. I am hoping i can still get some OK-ish recordings at night, the track is actually lit by Sodium vapor lights.
Currently looking at the Raspberry Pi HQ camera + Waveshare 18256 zoom lens. That would be around 100€ (plus the Raspberry Pi).
And when i have the final camera setup i'll have to tweak the detection a bit, some trains are getting sliced up and some not detected at all.
One problem with webcam-style USB cameras can be, that they do not output a fixed framerate, but may send fewer frames when the picture is not illuminated enough. If only a small crop rectangle is used, the motion detector gets upset that the train may move past its viewport within a single frame: "image is not wide enough to resolve the given max speed" (this also depends on max train speed and meters/px ofc).
The Raspberry Pi HQ camera module doesn't have this issue.
I might be escalating just slightly, this is an f1.1 Kanlam lens on the Raspberry Pi HQ camera, at 128 gain.