3 ms·

AFAIK the normal RPi boards only provide 2 MIPI lanes while 4 MIPI lanes would be possible by most camera modules and the processor. Therefore we only have half

AFAIK the normal RPi boards only provide 2 MIPI lanes while 4 MIPI lanes would be possible by most camera modules and the processor. Therefore we only have half of the possible the bandwidth available. For higher resolutions the bandwidth is a limiting factor. There are some boards and camera modules that use 4 lanes. Those boards use different connectors and therefore are not compatible with the default RPi camera cables this is probably the reason why the 4 lane option is not offered by default. In order to enable higher framerates you need to set up additional "modes" in some configuration file. I assume that by default only "relatively reliable modes" are configured. That's where the limitation to 120 FPS comes from. Calculating other modes requires some special tool that is specific to the camera chip. Also you need some luck that those modes actually work for you.

fps-hero 4y ago
It’s so frustrating that the entire CSI camera module ecosystem has been completely handicapped by the choice of connector for the camera module. The V1 camera module (OV5647) only supported two lanes, so it was a fair enough decision then, but they had a chance to change it when they changed connector on the PiZero. The connector even had the 4 extra pins specifically to support 4 lane CSI, but it was as if it was forgotten about. The V2 camera came out not long after so the combination would have made for a massive upgrade. I think they ended up back peddling from the new connector due to the horrific combination of a too thin custom flat flex cable with a connector that could barely meet its 10 mating cycle rating. It didn’t have to be that way, a standard 0.5mm FFC with decent swing down latch connector is 10x more robust.
- threatripper 4y ago
  I think this is a typical case of nice-to-have but not-important-enough for >90% of customers. The decision is not optimal but the want-to-change is not big enough to overcome the existing installation base. The new camera reinforces this. We could have a new connector with more lanes and a cheap little adapter PCB to adapt to the old connector and cables. But even that seems too much right now.

fps-hero 4y ago

It’s so frustrating that the entire CSI camera module ecosystem has been completely handicapped by the choice of connector for the camera module. The V1 camera module (OV5647) only supported two lanes, so it was a fair enough decision then, but they had a chance to change it when they changed connector on the PiZero. The connector even had the 4 extra pins specifically to support 4 lane CSI, but it was as if it was forgotten about. The V2 camera came out not long after so the combination would have made for a massive upgrade. I think they ended up back peddling from the new connector due to the horrific combination of a too thin custom flat flex cable with a connector that could barely meet its 10 mating cycle rating. It didn’t have to be that way, a standard 0.5mm FFC with decent swing down latch connector is 10x more robust.

threatripper 4y ago
I think this is a typical case of nice-to-have but not-important-enough for >90% of customers. The decision is not optimal but the want-to-change is not big enough to overcome the existing installation base. The new camera reinforces this. We could have a new connector with more lanes and a cheap little adapter PCB to adapt to the old connector and cables. But even that seems too much right now.