Brightness with the new QHY5III678m

[Empire4191]

Hello,

I installed the current SharpCap version.
Use the included USB cable from QHY.

Exposure works in EZCAP_QT(64 bits) and SGP.

In SharpCap, the brightness gets lighter from the image up to a certain point. From then on no more. Not even if I increase the exposure time or the gain significantly.

See screenshots.

1.jpg (178.51 KiB) Viewed 12102 times

2.jpg (177.1 KiB) Viewed 12102 times

3.jpg (177.02 KiB) Viewed 12102 times

[admin]

Hi,

I think that the QHY SDK is giving SharpCap back 12 bit data for the camera (maximum pixel value 4095) rather than 16 bit data (maximum pixel value 65535) - this might be an issue with the QHY SDK, but if so then there is no current update (you have SharpCap 4.0.9545, which uses the latest QHY SDK - 2023.02.28).

The other possibility is that there is some camera control that is reducing the pixel values down to a smaller range than the full range. If it was a colour camera, you could probably make that happen by turning down the various 'white balance' controls to low values, but I can't quite think what would do it with a mono camera.

It would be interesting to know the maximum pixel value that you currently get, since if that is not 4095 (or just a bit less) then the SDK bug is less likely. You can find that out by using either the 'Pixel Value Readout' tool or the main histogram.

cheers,

Robin

[Empire4191]

Hello Robin,

Thanks for the feedback. I only saw it now.
It is the mono version of the camera.
If I connect the camera via ASCOM, the brightness is correct. But the camera is just very slow.

When I connect natively, the histogram is on the far left.
I have now solved this by stretching the histogram a bit.

Screenshot 2023-04-02 184229.jpg (231.32 KiB) Viewed 11983 times

[admin]

Hi,

if my suspicion is correct about the camera levels being restricted to 4095 then the stretch will do no harm, but it would be nice to fix properly. Do you have the beta version of the QHY driver (released 10th March 2023)? If not, that might be worth trying. Otherwise we can ask QHY to check.

cheers,

Robin

[Empire4191]

Hello Robin,

Yes, I have installed the latest beta driver.

When stretching, I also had the impression that this did no harm.

[mjcanelson]

I am running the latest 4.1 version and cannot manage to get it to run either of
my QHY5IIIV2 cameras (678M/200M). When first plugged in the software runs
fine, but once on the telescope, the connection works and controls show up but
there are errors saying the camera won't go into live mode.

Any ideas?

[admin]

Hi,

do you use the same USB connections when on the telescope as when doing the initial testing? Adding longer USB cables (or even different ones), or adding hubs can cause issues with the camera responding intermittently or not at all. If you are using exactly the same setup and the telescope then this won't be relevant, but if you are changing things then check out the 'Troubleshooting USB Issues' link in the orange box at the top of the thread.

It may also be worth trying turning up the USB Traffic setting - that slows down the camera, but can increase stability.

If none of that helps, please share a log.

cheers,

Robin

[mjcanelson]

I had the QHY5IIIV2 camera working briefly on my setup after reloading the latest qhy beta
drivers. Since then it has locked up again. Here's an example log where SC tries but fails
to start live view...

[mjcanelson]

Sigh. I just installed 4.1.11433 and now the QHY cameras are both working again.
I'll run them for the next couple days and update here if they lock up again.

[admin]

Hi,

the only thing in the log is this line

Code: Select all

Warning	15:15:27.211463	#33	QHY camera failed to produce live frame of 20ms. Waited 20042ms and now giving up and resetting live view				in bool SharpCap.Cameras.QHY.QHYCameraProxy.GrabFrameLive(BufferFrame frame, uint width, uint height, uint bits, uint planes, Size size, CancellationToken token)

That indicates that the camera is not reporting any frames as being ready to SharpCap, but there seems to be no error from the camera, just no frames.

There are no changes to the QHY code between 4.1.11388 and 4.1.11433, so it seems like you have an intermittent error, rather than it being related to any changes in SharpCap.

It might be best to raise this issue with QHY - they have options to enable debug output from the SDK/Driver that may reveal things happening that SharpCap does not know about.

cheers,

Robin