Scott, nice pics. Good detail in the 1st one.
David, Your eyes process the info/photons instantly, unlike a 'film' or digital camera which accumulates them. It takes a very bright object for your eyes, 'CONES for colour' receptors to react/collect the light so that you see any colour.
As Andrew has said, you will see colouration in nebula, given a large aperture & seeing.
I've seen very slight 'green' in the Orion neb thru my 10", on nights of excellent seeing etc.
L.