Passing the time during all this rain...QHY8 Noise

[Astrobserver99]

I have been going over some of my data from a couple of months ago. Have hardly done any imaging with my new QHY8.

Looking at some of the bias frames, and comparing high speed and low speed download, there is a big difference in noise. Much less noise with low speed download.. STD about 15...compared to 50 with high speed download...I think this difference is do to my hub/ports rather than the camera itself...What STD do others get?

[multiweb]

Always use low speed download when imaging. Also pause guiding if you use the same USB cable to guide the mount through a hub. Finally shield the S-Video cable that goes from the DC-101/2 to the camera.

[Astrobserver99]

Can you expand on the pause guiding please. What is good shielding for the S-Video Cable?

Melbourne's dreary weather put me in travelling mood. I am halfway to Noosa at present.

[multiweb]

Oops! Sorry for delay in replying Rob. When downloading through a 'busy' USB line I used to get dots and trails during image download so since then I always pause the guiding to free the line when I download images. I use the same USB line to go to a hub where I have the QHY8, the mount and the guider (QHY5) using the same line.

The S-Video cable should have some kind of mesh in the rubber coating ideally that you can solder on both ends to the plug. Like a coaxial TV cable. The thin ones don't come with this extra cable shielding. In my case it did reduce greatly noise interference/banding in my pictures although I use ferrite blocks in all my USB lines too now. Better more than not enough :lol: