Am I unreasonable to complain about USB 3 performance?

[sophiecentaur]

The manufacturers seem to be comparing notes, because it is a rare feature that exists on both my ZWO and QHY cameras -- but with opposite settings.

Commiserations on all that. The cameras used on telescopes in major observatories just have to be better than that but I guess that involves ten times the cost as least. Zwo and the like are getting away with the sort of behaviour that DSLR manufacturers wouldn't. When you think of what an amateur level DSLR has inside it (mechanical and optical), the so called high end amateur astro cameras must be only 'average' value.
I was staggered to learn that the (usb2) ZWO ASI120MC was actknowledged by ZWO to 'give problems' with Apple systems. What possible excuse could there be for that if they are sticking to the spec rules in their cameras? It's only DATA fgs.

 

[shjacks45]

A Mac is theoretically BSD so it should catch hardware interrupts. I thought you might be a science type with a Raspberry Pi. Note that camera connector on the motherboard is not USB but I believe DCI, for direct sensor connect. High speed USB 2.1 is 480 Mega bits per second, assuming a minimal overhead and 10 bits per byte gives 48 Mega Bytes per second. If the camera is truecolor (4 bytes per pixel color info), 20 Megapixels x 4 bytes is 80 Megabytes. 80 Megabytes x 30 frames per second is 2.4 Giga Bytes per second. Serialized (x10) is 24 Giga bits pers second compares to SATA, USB3, PCIe, et al MAXIMUM 6 Gigabits/sec.
Q.E.D.