Hi

This was the most frustrating imaging problem I had ever come across ! One thing you require from an imaging set up is reliability but you never knew when this problem would raise its head and destroy an automated session !

The issue went away in my rig when I started using the RPI4 4 GB version. I suspect the cause of it is to do with the combination of the specific USB bus architecture which the particular platform utilises and the protocol that ZWO uses to effect a data transfer to the host. The RPI4 is far superior to its predecessors both in terms of memory, processing power and bus architecture. I believe the usb bus is more dedicated and not shared with other resources like the network and operates at usb 3 speeds which immediately makes it more compatible with my ASI 1600mm-c which was the unbuffered version ! I am using the hub provided by the camera which also hosts the guiding and Atik filter wheel and I do not get this problem now.

I have a feeling that if the usb bus is more of a shared resource, then depending on how device priority is assigned on the bus, the data transfer protocol when downloading an image (which I guess needs high priority at the time of transfer) becomes unreliable due to bus contention issues. All this is dependent on the particular hardware platform architecture and hence the problem is not solely due to a single bit of software or hardware but is system dependant - which helps explains its multiplatform nature.

I hope that helps !

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