Hi Robin/All, For occultation work i have the setting at zero, but for longer exposures i use the same setting and banding suppression.
I read on the QHY web site (for the QHY600 Pro) that some banding is "periodic" and can be controlled (minimized) by the USB traffic setting.
Would i expect this to work in SharpCap ?
Cheers
Tim
(Abingdon)
Does USB traffic setting effect horizontal banding?
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Re: Does USB traffic setting effect horizontal banding?
Hi Tim,
yes, it's quite possible for that to have an impact. On the QHY cameras, my understanding is that the lower the setting, the higher the speed the internals of the camera run at, giving faster frame transfer rates (and potentially reduced stability).
Additionally, I'm also of the opinion that the horizontal banding often arises from voltage fluctuations on the power supply to the camera sensor - I've seen cases with horrible banding on a desktop computer or a laptop on mains, but it goes away when the laptop is on battery, presumably because the mains power introduces a ripple into all the voltages in the computer that gets into the USB voltage and then affects the sensor.
Given these two, there may not be a *simple* relationship between the USB speed setting and the banding - the best thing to do would be to set up your usual exposure/gain/etc, then set as strong a stretch as you can in the SharpCap display stretch so that you can see any banding in dark frames - you can then experiment with the USB setting to see if you see any noticeable effects.
cheers,
Robin
yes, it's quite possible for that to have an impact. On the QHY cameras, my understanding is that the lower the setting, the higher the speed the internals of the camera run at, giving faster frame transfer rates (and potentially reduced stability).
Additionally, I'm also of the opinion that the horizontal banding often arises from voltage fluctuations on the power supply to the camera sensor - I've seen cases with horrible banding on a desktop computer or a laptop on mains, but it goes away when the laptop is on battery, presumably because the mains power introduces a ripple into all the voltages in the computer that gets into the USB voltage and then affects the sensor.
Given these two, there may not be a *simple* relationship between the USB speed setting and the banding - the best thing to do would be to set up your usual exposure/gain/etc, then set as strong a stretch as you can in the SharpCap display stretch so that you can see any banding in dark frames - you can then experiment with the USB setting to see if you see any noticeable effects.
cheers,
Robin