QHYCCD

New drivers changing sensor data?

New drivers changing sensor data?
« on: July 14, 2018, 02:48:27 am »
Hello,

I upgraded the drivers for my QHY183C about 3 weeks ago. Since then, I've had problems processing my images with the result of calibration (bias + dark + flat) extremely dark with only a few stars appearing. It took me a while to realise that it was because the calibration images no longer matched the images produced by the camera. So I re-made all of them (bias, dark, and flat) and recalibrated one of my images. With the new calibration things were as expected.

Looking at the darks for example, I can see that the signal is much much lower now than a few months ago, with a mean of 3.8887e-02 for a dark taken in March, and 1.9323e-02 for a dark taken last night (both 300 seconds, -10C, gain 11, offset 20, bin 1x1). That's nearly half the signal. Note also that the minimum and the standard deviation are now much lower, so the new darks are indeed much fainter and flatter than the old ones, which is consistent with my experience processing using them.





Is it possible that the drivers somehow convert the sensor signal differently? It's a bit as if the gain setting was ignored. Or is it that my camera is now defective?

Here are the 2 darks: one from March and one from last night for comparison.
http://www.raguenaud-online.org/cedric/photos/astro/D_2018-03-15_23-07-15_Bin1x1_300s__-10C.fit
http://www.raguenaud-online.org/cedric/photos/astro/D_2018-07-14_02-30-58_Bin1x1_300s__-10C.fit

Thanks
« Last Edit: July 15, 2018, 08:33:45 am by cedric »

Re: New drivers changing sensor data?
« Reply #1 on: July 15, 2018, 09:04:29 pm »
Hi,
    Could you send these FIT file to me by DropBox or other way?I can't check or download them by your link.
    And whether it can go back previous status if you use previous driver?
Best Regards,
QinXiaoXu

Re: New drivers changing sensor data?
« Reply #2 on: July 16, 2018, 01:57:05 pm »
Hello,

Here are the files again: https://drive.google.com/open?id=1-4AoAbsUJs5fUX3E7r8Ucpie_La1ydj2

D_2018_03_15 is before upgrade.
D_2018_07_14 is after upgrade
D_2018_07_16 is back to the old drivers.

Using the old drivers does seem to produce files similar to before the upgrade.

Thanks.

Re: New drivers changing sensor data?
« Reply #3 on: July 16, 2018, 08:09:20 pm »
Hi,
    If you use old driver(20171221),it's normal,if you use newest driver,value is not normal,right?Which version of SDK do you use?You can try to use 171221 and 180502 these 2 versions to check if it can have vary?
    And I have no permision visit the file,my google account is qhyccdqxx@gmail.com.
Best Regards,
QinXiaoXu