Shame digital exposures kick up so much noise during long exposures though.
What do you mean by noise in this context?
Do you mean that a smooth, even surface looks uneven, meaning that adjacent pixels which should be the same colour are slightly different? This effect would cover the entire picture. Similar to the effect that you get when you crank the ISO right up.
Or do you mean that there are occasional "hot pixels". I count perhaps 4 in the FF version of my competition entry, which is a 30 second exposure.
If you mean the second, then I would like you to define "long exposure" and pick a suitable ISO... I would be interested to compare a picture of the inside of the cap on your Nikon with the inside of the cap on my 5D and count the spots...
Andrew