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- I have bought a Cmos camera for astronomy. It is sold as USB3 but it will not talk to my computer reliably. Astro 'users' just say it's a known problem and are prepared to work around but I don't think that's good enough.
USB 3 was heralded as the next best thing to sliced bread and, imo, has been marketed in a not - too - honest way. It's not always as useful as the bare numbers suggest. I know the same could be said about 1GB Ethernet but Ethernet can handle all sorts of rag tag and bobtail traffic streams and STILL WORK. I guess the Engineering of Ethernet is a lot more mature and the Internet just has to work.
Astro cameras are often required to transfer image data pretty fast and the movies that are shot to get good planetary images need a good data rate. USB3 claims 5GB/s but that figure is only when things are 'just right'. I am well aware of that and my expectations are realistic.I bought a low-end ZWO ASI290 MC camera with a 3MB sensor. Sometimes I get half decent images. With the short, supplied lead I have had 100 frames per second at times but mostly the capture programs hang up. I can accept speed restrictions but is there any excuse for hang-ups? If I have a box that produces data for transmission to another box, I would expect the comms channel to know about the channel capacity and to regulate the data transfer rate to fit. Using the camera (and others) with a USB2 lead, the frame rate goes up and down, according to cable lengths and other traffic. I can't think there's any excuse for the USB3 shortcomings.Afaics, USB3 is very much a bolt-on system. The connectors have two data wires which give USB2 compatibility and then, in another part of the connector, two twisted pairs provide fast duplex comms. I know it's busting its little braces to achieve 5GB/s but when a system fails, it really should fail gracefully
I have a question about the "USB Traffic" control that some capture progs have. ZWO have told me to fiddle with that control and it does have some effect. It could allow some control of priorities amongst several data streams - potentially very useful but that still doesn't allow it to work unless things are just right (and I don't know what that actually means). The poor computer has frozen completely on occasions and works as soon as I pull out the camera cable. Crazy.
It's like trying to get a racehorse to pull a milk cart. And it shouldn't be like that. Are the chips just not up to requirements~?
Astro cameras are often required to transfer image data pretty fast and the movies that are shot to get good planetary images need a good data rate. USB3 claims 5GB/s but that figure is only when things are 'just right'. I am well aware of that and my expectations are realistic.I bought a low-end ZWO ASI290 MC camera with a 3MB sensor. Sometimes I get half decent images. With the short, supplied lead I have had 100 frames per second at times but mostly the capture programs hang up. I can accept speed restrictions but is there any excuse for hang-ups? If I have a box that produces data for transmission to another box, I would expect the comms channel to know about the channel capacity and to regulate the data transfer rate to fit. Using the camera (and others) with a USB2 lead, the frame rate goes up and down, according to cable lengths and other traffic. I can't think there's any excuse for the USB3 shortcomings.Afaics, USB3 is very much a bolt-on system. The connectors have two data wires which give USB2 compatibility and then, in another part of the connector, two twisted pairs provide fast duplex comms. I know it's busting its little braces to achieve 5GB/s but when a system fails, it really should fail gracefully
I have a question about the "USB Traffic" control that some capture progs have. ZWO have told me to fiddle with that control and it does have some effect. It could allow some control of priorities amongst several data streams - potentially very useful but that still doesn't allow it to work unless things are just right (and I don't know what that actually means). The poor computer has frozen completely on occasions and works as soon as I pull out the camera cable. Crazy.
It's like trying to get a racehorse to pull a milk cart. And it shouldn't be like that. Are the chips just not up to requirements~?