Graeme, there is not much to critique here. More of a case of individuals likes and dislikes with the trees/foliage being included in the top of the image. A man of your standing would have made this decision either because of your own taste or that of the buying public. Wonderful colours and light. It should sell well to its intended audience. Interested to hear more of the techique of the double exposure as I notice that both are of the same f-stop and I'd of thought that the 1 secs flash would've made little difference, but obviously it does. I use the technique occassionaly in the darkroom (currently being built, in fact I'm typing this whilst waiting for the electrician) so I understand the thinking behind the process. Take care, Carl.
Carl, the 1 second flash was made about 90 minutes after the city exposure, so there was a lot of light in the sky by then. One second was set from using the spot meter on the sky, while the earlier exposure of 3 minutes was set from spot metering the roads in the mid-ground.
The tree was indeed intentional, and cropping it out was an option I looked at but rejected. There are too many other photographers shooting "Pano" and I try to be different when I can.