Thanks minnie.
Yes it is one of many species of eucalyptus. Too many for me to know. There are many with similar thin bark with variations in colour. Ghost gums have a quite shiny light silver / grey. River red gums tend to red / orange and when they shed the outer layer the new one can be very distinct. The one here has a cousin that is a brighter green with less (but still some) grey. They can all look different depending on the ambient light - time of day.
I wouldn't normally crop so tight but there was some fringing along the edges of the tree - perhaps due to hazy bright light - and with only indistinct sky as a background there was no point in keeping it.
I will think about increasing dof in the future to see if I can get the bark more in focus...