I purchased my QHY128C two years ago. I never really got past plugging it in and testing operation.
This fall I tried again. It could not produce an image.
It was repaired in China after two months. Now it downloads images fine. I found another problem as I started using the camera.
I first noted that the image center was offset by about 1000 pixel in X and 500Y. The sensor appears centered using a ruler in the camera .
The QHY128C comes with an adjustable front end piece with three screws
that allows for some lateral adjustment. However, a 1000 pixels exceeded the range. I have a lathe and removed 2mm from the adjustable front piece.
I am was now able to center a star and rotate the camera in the focuser without lateral shift. Offsetting the sensor took 2-3 mm.
I could not understand why the image was so far off center.
Next I did a plate solve ( this is where the plot thickens )
I measured 1.21 arcsec per pixel and FOV 2.03 x 1.37 degrees with TheSkyX's image link plate solution.
The scope in an AP130 f6. I verified that the scope has a FL of close to the specified 780mm focal length using a ruler.
The predicted FOV should be about 2.64 x 1.76 degrees at 1.58 arcsec per pixel. This is using a 780mm FL scope and a 128C camera specified with 6036 x 4028 pixels @ 5.97u.
The plate solution at a FOV 2.03 x 1.37 and 1.21 arcsec per pixel suggests that scope has 1020mm FL. This is most decidedly not true.
I have determine that the camera likely has much smaller pixels ( about 4.7-5.0u) and is not using all the pixels on the sensor.
I am keeping in mind the fact that active imaging area is substantial offset.
I don't know if it is possible to install a 367C sensor and configure to readout a sub-frame using firmware.
The 367C has 4.88u. This would fit the measured offset and plate solution.
Kind of sucks too. I want the FOV.
What do you think?