Only things to add are that 5D2 has very little ISO noise up to around the 800 mark. Most people find the ISO noise becoming objectionable between 1600 and 3200 depending on their own tolerance level and willingness to lose some sharpness cleaning up the noise.

Not sure where yours is at, but you may be able to bump ISO for faster shutter speeds to see if that helps. Those with rock steady hands can use longer shutter speeds than the rest of us.

Long exposure times will also increase noise levels due to the sensor heating up.