I was guessing 5' 20" as a rough guide so sounds like I shouldn't be too far off. Always amazes me just how much latitude there is in film. I've accidentally pushed EPP100 to 1600
and got quite useable results - I wouldn't want to make a 10 x 8 out of a frame but for scanning and tweaking via photoshop (I know that it's non u on this forum but let's face it digital manipulation can save your bacon at times especially if it's a once in a lifetime family shot and your wife will have your nuts if you don't have something for the relatives
) it was presentable enough.
I'll give it a bash tomorrow and see what comes out at the end.