A friend of mine did something similar to this but using cast iron manhole covers only. You have gone even further, and successfully so, by highlighting what we probably don't notice and take for granted. The different forms of grid, in shadow and reality, work brilliantly together.
Thanks Tom. I'm quite partial to the odd manhole cover too - Prague is especially fertile ground for them! It was a good day for shadows and I wanted to exploit the various surfaces as well.
I am pretty daft when it comes to shadows and shades, they normally scared me a few years back, But Pete, these feel quite soft and harmless like an embrace.