My olives on the tree in October

I wouldn't say that I have lots of olives on our tree this year, but they are the most I've ever managed to grow to full size. They are dotted about the large tree's branches, but I can't work out why any particular olive fruit has been produced in any one place, and grown to this size. Nor do I think they will be edible, though I will try to eat one. It is probably time to harvest them and have a taste.

The red leaf fell from a nearby hedgerow but as I liked the colour I didn't remove it from my view.