[sharkbite]

Hi Folks...

I'm looking at getting a relatively cheap, dedicated astro camera
and relieve the Canon 7d of its duty.

I have a Meade 8" LX90, and will use it mostly for planetary movies ,and the odd
DSO "long" exposure. (I don't have a wedge, so <30 seconds mostly)

I have read lots of rave reviews about the ZWO ASI120MC type cameras,
and am trying to decide between the USB2 or USB3 variants. My Lappie has a USB3 port so either will work.

My question is:

What is the material difference between the two?
Is data rate down the cable that critical if you are typically doing long exposure?

Any advice or related experience would be most appreciated.

cheers,