Sunset twilight

This is a classic picture of Florence, Italy. The crowds now are dense in the Michelangelo Plaza above the Arno River, which is the place from which this photo is normally taken, so I found another location where there was no one else and the medieval buildings were spread out nicer. I used a 100-400mm lens to fill the frame, and as I now do habitually, I shot with a 5-frame HDR sequence with one f/stop increments. My aperture was f/5, the ISO was 200, and I used a tripod with a 10-second self-timer in lieu of a cable release. It's interesting to note that because I was shooting toward the west, I captured sunset colors which mixed nicely with the twilight blues of the cityscape. Had I been shooting in an easterly direction, the sky would have been cobalt blue.