A couple of days ago, I mentioned in the comments that dog is not imperturbable. She is perturbable (if that's a word). Lovely sunny mornings are all very well, but they do tend to bring out other things besides dog walkers; things like hot air balloonists. These are dog's absolutely least favourite things in the whole world.
Here it is. Long distant, but they don't have to be close.
Sheep know the dog's there. Dog has not yet spotted the HAB.
Now she has. Lead on at this point - if not, she will bolt. I thought the HAB was probably far enough away not to bring on total hysteria, so we carried on the walk. Dog was brave, and managed to survive by sticking close to my legs.