I have been trying to shoot Ison myself. It is actually out the window as I type but I’m west of downton Denver and the city lights are too much plus the moon has not set.
We will try again in early December when Ison is on the other side of the sun and will be visible in the dark west sky. By then it could be spectacular as it had passed less than 1M miles from the surface.
I think they have in common that green tail.