Re: GPS Flash device for precise timing
Posted: Fri Mar 22, 2024 10:45 am
Hi Steve,
most cameras do not report dropped frames from their SDK, meaning that any dropped frames reported by SharpCap are a result of the SharpCap code detecting something anomalous (timeout fetching frame data, etc). The exception to this is ZWO where the SDK does report dropped frames, although there is no guarantee of how this is implemented internally.
For QHY cameras with GPS, the frame has a sequence number, so SharpCap will flag a dropped frame if there are missing sequence numbers. In the QHY case, the sequence comes from the GPS hardware/FPGA, so we know it's not a number generated in software on the PC. I don't know if other cameras have this sort of feature (never really considered it before), but even if they do, unless it comes from the hardware it is not much use.
Note that SharpCap may flag dropped frames for a lot of causes not related to the camera (for instance if you have some image processing active and it takes longer to process a frame than the gap between consecutive frames). To see the details, you can check out the SharpCap log which records the number and types of different categories of dropped frames from time to time.
cheers,
Robin
most cameras do not report dropped frames from their SDK, meaning that any dropped frames reported by SharpCap are a result of the SharpCap code detecting something anomalous (timeout fetching frame data, etc). The exception to this is ZWO where the SDK does report dropped frames, although there is no guarantee of how this is implemented internally.
For QHY cameras with GPS, the frame has a sequence number, so SharpCap will flag a dropped frame if there are missing sequence numbers. In the QHY case, the sequence comes from the GPS hardware/FPGA, so we know it's not a number generated in software on the PC. I don't know if other cameras have this sort of feature (never really considered it before), but even if they do, unless it comes from the hardware it is not much use.
Note that SharpCap may flag dropped frames for a lot of causes not related to the camera (for instance if you have some image processing active and it takes longer to process a frame than the gap between consecutive frames). To see the details, you can check out the SharpCap log which records the number and types of different categories of dropped frames from time to time.
cheers,
Robin