LDunn wrote in post #17483757
Thanks everyone for the kind words.
Dave - so embarrassed, you'd think with the Irish name I'd been given (Liam) I'd have spelled St Paddy's day right

no probs Liam .... happens to the best of us 
Good call on the flashlight beam, I agree it looks silly - wanted to see how it would turn out and it definitely takes much away from the natural beauty.
we live and learn
I'm lucky enough to see the aurora several times a year, but I'd really like to get a good lens for capturing them better. Right now I'm using the EFS 10-22 on a 7D. Any suggestions?
I moved from Dunedin, southern NZ 46 deg S), where I have seen and photo'ed countless dozens of aurora between 1970 and 1999
to Sydney (~ 32 S) where I have never seen one Wife and I did head a bit further south in the nite of the 17th
but couldn't get out of the cloud 
10 - 22 is as good as any, nice wide angle but remember that's going to be around 17 - 35 on your 7D crop sensor
still good !
you didn't say what its f stop range is ?
I'm looking at getting one of these for my 5D3 .... http://www.digitalcamerawarehouse.com.au/prod9852.htm
Samyang 14mm f/2.8 Lens ... they are getting great reports
keep in mind your exposure times aperture and ISO .... Auroral displays can have a lot of movement in them
longer exposures will just blur the auroral curtain details into a mass of colour which may be good for a couple of pics
but you really want to bring out the details of the curtain, rays etc as well, so shorter exposures, less than 30 sec
5 - 20 sec, widest aperture and don't be afraid to experiment with ISO's up to 2500 on your 7D when using shorter exposure times
Also I need to find something interesting for a foreground shot.....that's the next mission.
yup ... its no different to doing daytime or other general nitetime landscapes
so keep in mind things like lakes / ocean for nice reflection the black silhouette of a bare ( few branches, winter time no leaves etc) tree off to one side. Or silhouette of a person looking up at the sky. Nice star field in the background of the aurora eg Milkyway
bracketing the aurora between hillsides of a valley
Of course all these things and the ability to do them depends on where you life and the landscapes you have in your region
Above all, have fun experimenting 
cheers
Dave