I just purchased a ZWO ASI 178MC to go with the ZenithStar 61 and Raspberry Pi 4. One of the reasons I went with the USB 3.0 ZWO was the very slow frame transfer rate from my Canon 600D when polar aligning etc. The 178 is supposed to run at 30-60 fps according to the specs.

Testing it on Stellarmate with Video preview or Looping shots I get from 0.1 - sometime 5 fps but mostly just above 1.2.   Is that expected ? Granted the time to download an image from the camera has dropped from 10s for the Canon to 1.5s for the 178.

I'm using a Pi4 and its blue USB 3.0 socket and the supplied USB 3.0 cable from ZWO.

I thought at first it may be the write speed of the SDCard (Class 10 but who knows) so I switched to running SM from a SSD without any improvement.

Just wanted to ask people who are already running this sort of setup with SM.

Thanks

Yes RPi have weak CPU so that 5FPS is within expectations. With my ASI1600 I get around 2FPS without writing it to card. I wrote myself barebone program that downloaded frames from camera as fast it was possible. I could get up to 5FPS or 170MB/s data rate while normal PC could go up to 400MB/s. That was just downloading to RAM and nothing more.

Thanks Nou.

Saves me searching for a problem that isn't there.