COLOURING IN THE DETAILS

What all this means, is as you witness the aurora, especially as you're getting used to what to look for, your eyes will usually pick up the brightness of the colour green much more easily than it will the deeper magentas. All the colours of the aurora are visible to us, but everyone perceives differently and will have very unique experiences. 
So to speak from my personal experience, there have been nights I've seen some reds. Purples and pinks; weekly, and green of course almost nightly. The northern lights can become so bright, they'll light up an entire landscape to the point, where on a moonless night, you'll be able to read a book under them. Just don't expect to see the atomic greens and neon pinks some tourism agencies like to push into print...