Fog bow at Watchtree

If you look at these two pictures, you might be able to discern two halves of a white arc. It was clearer through my polarising sunglasses and by tilting my head from side to side I could see that it was polarised because it disappeared with my head tilted at certain angles. With my hand as shown in the bottom picture, I am measuring 25 degrees. https://oneminuteastronomer.com/860/measuring-sky/ The radius is bigger than this. https://www.atoptics.co.uk/droplets/fogform.htm gives the radius as between 30 and 45 degrees, which sounds correct. When a rainbow is formed, larger droplets of water refract light giving the colours. Here the droplets are much smaller and diffraction dominates. https://www.metoffice.gov.uk/learning/optics/rainbows/fogbow