Paramedungey and Tricia, Thanks guys! One of the things I really wanted to try and achieve was to not make the windmill and sails look too flat. The shading needs more work and I’ve noticed now I forgot to shade the ball on the top of dome! Doh!!!

Here's how the curves should look on you windmill, also the 'box' on the side looks like you can see a bit too much of the top. We would need to be much higher above it to see that angle of perspective. I've also put a bit more shading to see if that makes it rounder.

love the sky! I think the base of the windmill looks round, but somehow the white top section does look a little bit flat. Maybe a bit more shadow on the right side of it? But it's a very nice painting.

The sky and tree are very good ,maybe the green lines down the field could be not so harsh.apart from that good picture,Mark.