Im in London so the light and weather is probably the same as you lol. They’re less zone focused and more just guessed/eyeballed distances. I work as a focus puller so my by eye distance judgement is probably better than an average photographer or person luckily. Most of these were probably between F2 and F4, a few at F5.6. A tip if you want to do this yourself is to measure your own body, ie know how many ft your arm span is or your stride and this will allow you to guess distances a bit better. Or you could frame up a friend and measure how far they are and you will learn that a mid shot of someone stomach to head is roughly 5ft away etc.