ASI174mm longer exposure problem

w7ay

avdhoeven I ordered a new cable, but somehow I don't think that is the issue.

The fundamental issue is not the cable, but the USB port in the camera. The USB ports in ZWO devices don't appear to be designed with enough engineering margins (voltage, frequency and temperature).

If that is the problem with your camera, by "tuning" with different cables, the ports could often be coaxed to work.

If you are using the USB cable that came with the camera, try and replace that with a good cable that is just long enough to connect your camera to the ASIAIR. Find a cable that advertises 20 AWG conductors for the voltage and ground pair. Do not be tempted by thin cables. And certainly do not use cables that are unnecessarily long to require them to be folded or coiled -- coiling a cable causes all sorts of problem with unshielded data pairs.

ZWO keeps recommending that people try with different cables, without admiting that the root problem is that their USB interfaces are not designed with sufficient margins to handle all USB cables.

Chen

avdhoeven

w7ay Thanks! I have ordered a cable from Pegasusastro with 28Awg power and 24Awg data, so hope that will help.

w7ay

avdhoeven 28Awg power and 24Awg data

28 AWG is way too thin to carry power. 24 AWG for data is fine as long as there is no ground loop.

Just browse through Amazon or electonic parts suppliers like Mouser or Digikey. Buying cables from a boutique store is just throwing money away for something that that are just rebranding.

Chen

avdhoeven

w7ay I swapped the values I see now 🙁 It was 24 for power and 28 for data... It's from a premium astro supplier here, so if it's bad I'll return it.

w7ay

avdhoeven It was 24 for power

That's still a little thin, but should be OK with a small sensor like the ASI174.

I just did a quick look at Amazon and found even a USB 2 cable with 20 AWG; so they do exist. In fact, most of the long USB cables at Amazon have 20 AWG power wires.

Chen

Tech@ZWO

Tech@ZWO We checked the log, but didn't find the exposure command, can you reproduce the problem and upload the log again?

avdhoeven

Tech@ZWO I'll see how to do this later. Strange thing is I did an exposure and it gave me the failure, but the exposure was in the guide module, so maybe that went wrong? I'll see what I can do.

avdhoeven

I have uploaded a new log. I now also have tried the ASI174mm as main camera and also got an error when doing an exposure longer than 1 second.

I already have switched the cable, but this didn't change the problem 🙁

Basically this is what I see now:

On the asiair I can't take images longer than 1 second with my ASI174mm
On my macbook using ASIstudio of firecapture I can't take images longer than 1 second
On my macbook using Nebulosity I can take images with any exposure without a problem
On windows in a virtual machine on my macbook I don't see issues and can take any exposure time.

I just don't get a grip on it. Could maybe be some driver issue? Hope @Tech@ZWO can find anything in the new log.

Tech@ZWO

avdhoeven Got it, thanks.
Is it possible for you to do more test? connect it to the USB 2.0 port on the ASIAIR, then try long exposure, will it work?

avdhoeven

I'll do that! Never realised there are usb 2.0 and 3.0 ports. I will see if that makes a difference.
Thanks!

avdhoeven

avdhoeven I tried with all 4 ports. No difference unfortunately...

Tech@ZWO

avdhoeven If THE EXPOSURE failed problem can be stably repeated, your camera needs to be shipped back for repair, please contact the seller for after-sales service.