Many many thanks for the detailed and creative comment, Joe! I understood it up to the rotation. But then I must confess that I lost track of what you did. So, to my shame I have to ask:
1) What is the perspective correction? How did you do that?
2) What is an "Equalize filter?" How/why do we use it? How does it make the halos evident?
3) Did you used a gradient, like these available in PS to replace the sky?
Though I am very greatful for your ideas/work, I must say that I don't quite like the flattened up perspective of your altered photo. And the water doesn't look very appealing to me. Oh well, I don't know much about digital manipulations, so this is only the humble opinion of the beginner.
Interesting photo. But I thought some brightening, and a crop, might highlight both the facades and the birds flying above and in front. I rotated to the right, slightly, as well, and applied a slight perspective correction.
I selected out the birds, above, because it appeared that there were highlighting or sharpening halos in the original, which became evident if subjected to an Equalize filter. I recreated the sky gradient, and then punched the birds in over it.
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