Cheers Charles ,
I can see that now and I will keep that in mind when I next do something like this .
It was a great exercise for me as I was trying out shots that I new I couldn't achieve with my 400d and 17-40, one which also made me reflect on my initial judgement of the 24-105 (born out of ignorance) that it wasn't the lens for me.
How wrong was I as I now love it .
Although a 135 F2 is one I'm on the look out for next.