Photographers talk of "The Golden Hour". This is the hour around sunrise and sunset when the light from the sun is scattered just so and you get some nice lighting effects. It's not really an hour, and it varies from day to day and where you are on the planet, but if you are going to take pictures of Hull Fair I recommend trying to arrive around 6:00 in the evening when, if the weather is right, you can get a little bit of golden hour goodness.
We went on Wednesday and headed straight for the big wheel. Which this year was really big. I had my fisheye lens for the maximum coverage of the scene and I'm also playing with a plug-in filter for LightRoom (the program I use to import and manage my photos) that converts the fish-eye view into something like a normal wide angle. I'm quite pleased with the results.