QHY678M Live View slows down after a few seconds

[eyecon]

Hi,
I'm having a problem getting realtime live view from the QHY678M camera. I see the frame rate indicator running at about 40FPS depending on the ROI but no matter what memory, USB, GPU acceleration settings I tried, live view starts great and after 200-300 frames slows down to something like 1 frame every couple of seconds while the FPS indicator still shows a much higher frame rate. I have my live view memory set as high as it will go(about 8GB) and GPU acceleration turned on. I have tried the following with no impact to the behaviour: Turning GPU acceleration off , reducing the bit depth from 16 to 8, reducing the ROI to the lowest possible settings, changing the USB Traffic slider from 0 to 60. I turned on camera communication and performance logging and I do not see anything abnormal reports. I'm using latest Sharpcap Pro 4.1(1.2221) on an N100 mini PC with 16GB of RAM and latest update of Windows 11(as of today).

[admin]

Hi,

OK, so if the FPS indicator at the bottom left is staying at about 40fps then the camera is still working as it should sending frames to SharpCap, so it sounds like SharpCap is being bogged down and ending up lagging on the frame display. What could be happening is that SharpCap has a display frame rate limitation system that tries to slow down the update of the display if the CPU load for displaying the images seems to be getting near to 100% of one CPU core. That would tend to drop the frame rate down to about 1fps over a few seconds if it detects CPU overload (or thinks it does). Unfortunately it doesn't log anything about that happening (I will correct that).

On the assumption that it is the rate limiting kicking in, there are some things to try

1) Make sure you have the correct graphics card drivers installed (probably Intel built in graphics drivers) - they will hopefully be higher performance than if you are using the fallback 'Microsoft Basic' graphics.

2) Try with direct connection (monitor, mouse, keyboard) rather than remote connection if you have been using remote to see if that helps

3) If you are using the display in high DPI mode, try reducing the display resolution to 1920x1080 or lower

4) Try using ROI or binning on the camera to reduce the amount of data in each frame to see how/if that helps.

cheers,

Robin

[eyecon]

Thanks Robin. I’ve tried binning and using a very small ROI but unfortunately neither helped. I’ll do some indoor tests with a display directly attached and also try to lower the resolution of the RDP session to see if that helps.