Images stop being registered requiring complete restart of Sharpcap

[AstroTupelo]

I am running version 4.1.12395 64 bit with a lifetime Sharpcap Pro license and am having freeze ups every session. This usually happens during live stacking but has also happened during dark frame capture. The last session while capturing 20 dark frames of 10 seconds to create a master dark frame, about halfway through I noticed that although the individual frame progress line kept building and then resetting every 10 seconds representing each frame capture, the number of frames shown was not increasing and the estimate ETA kept increasing by one minute every minute. I finally hit cancel but it would then not register any frames. I shut down Sharpcap and brought it back up quickly so that I could maintain the cooled temperature I had reached of -5 and once restarted it worked and I was able to complete my darks. Then twice during image acquisition on my target it suddenly quit registering frames during Live Stack. Again the individual frame progress bar was steadily running, and Live Stack was not showing any dropped frames, but it was also not showing any added frames. Each time I had to completely shut down Sharpcap and start again to continue. I also have the 32 bit version of the same version number and also another older version, and I tried switching to the 32 bit version and at first thought that was the answer, but it eventually did the same.
My computer is an Evoo Intel core i7 7560u, 256GB SSD, 8GB memory, Windows 10 computer that I purchased specifically to run my camera only with Sharpcap and have never used it for anything else and do not have any extra programs installed. I do not do any processing of images and always transfer the captures for each night to a separate drive and then delete the files from the laptop to make sure I always have enough memory. I also keep the wifi off and the computer in airplane mode to prevent any strange unexpected updates or changes to happen once I have everything working as I want.
So I am really puzzled as to why it keeps stopping accepting frames. Any ideas? Is this a known bug that has been resolved with newer versions? I would appreciate any information.
Thanks, Ken

[admin]

Hi Ken,

from your description, it sounds as though the frames have stopped being sent from the camera to SharpCap. In this situation, SharpCap does its best to recover by giving up waiting after a certain amount of time (maybe 40s for a 30s exposure - it depends on the brand of camera) and re-sending a request for a new frame in the hope that the previous problem was just a glitch. If it wasn't a glitch but was some more serious problem then the same thing happens again. You will usually notice that the number of dropped frames reported in the status area at the bottom left of SharpCap is increasing when this happens.

The most common causes for this are USB data transfer issues. Things that can help resolve this sort of problem include

* Remove any USB extension cables, hubs or long USB cables - test with a single, good quality, USB cable of under 2m length
* Turn *down* USB Speed/Turbo USB settings in the camera settings. Higher values of these tend to give higher frame rates, but more problems with stability (exception: QHY cameras - turn up the USB adjustment for more stability)
* Bring the USB cable from the camera straight back to the laptop - if you connect other equipment like mount/focuser/etc, bring those to a hub and then back to a separate port on the laptop.

You'll find more details on these suggestions and other hints on our USB troubleshooting page : viewtopic.php?f=18&t=349&p=1556#p1556

All of the above is a little generic, since you didn't mention the make/model of camera you are using.

cheers,

Robin

[AstroTupelo]

It does not show any frames being dropped. The dropped frames still shows zero and the frame acquisition bar keeps refreshing as if it is capturing frames but no frames show added or dropped. And I was doing 10 second captures and it never gave up even after several minutes of waiting. When it did this during capturing dark frames the estimated time of completion for capturing 20 dark frames kept increasing by one minute after each additional minute of time but showed the same frame count received at that point and the same remaining to complete the master dark capture.

My camera is connected directly to the laptop with the cable provided by ZWO and I have not changed any USB settings.

Something is not right but I cannot figure out what is going on. It is like a freeze of additional frames only, it will let you cancel out of the dark capture, or capture out of the Live Stack, but if you go straight back to opening the dark capture panel or Live Stack function without shutting Sharpcap completely down, it still will not add any frames. As soon as you close out of Sharpcap and open it right back up everything works as it should for an undetermined amount of time until it does it again, which is sometimes a matter of minutes and sometimes it may last long enough to complete that imaging session, but it has done this every time I have used Sharpcap for the last half dozen times or so.

[AstroTupelo]

Sorry forgot to mention the specific camera, it has done this with my ASI533MC Pro during deep space imaging of fits files and also froze up with my ASI678 during planetary SER captures. Most recently and during the dark frame capture it was with the ASI533

And also if it were a cable problem or USB setting I would not think that shutting Sharpcap down and bringing it immediately back up would have it function correctly. If the cable or setting was preventing something from sending it seems it would still be causing the problem 10 seconds later, because I closed Sharpcap hurriedly and reopened to prevent the temperature from dropping on the cooled camera, and as soon as it is closed and opened back up it runs perfectly, until it eventually suddenly doesn't agian.

[admin]

Hi,

have a look at the SharpCap log (or post the log here). Particularly if your exposures are more than a couple of seconds, SharpCap will record in the log if it fails to get a frame from the camera and is trying again. Also, make sure you have updated to the very latest version of SharpCap 4.1, as I added some code maybe a month or so back that attempts to reset the ZWO camera if there are missing frames for more than 60s - it's possible that this software reset will recover the situation in the same way that exiting and restarting SharpCap does.

cheers,

Robin