So the off-camera setup was the SB-800 mounted on a Yongnuo YN622N i-TTL wireless flash trigger/receiver, which itself was mounted on a Calumet light stand using a swivel/tilt flash holder. Mounted to the SB-800 was a 10x14" LumiQuest SoftBox LTp. Supplementary power for the SB-800 was provided by an SD-8A battery pack.
For the earlier evening shots with more available light, I placed the flash at around 6.5 to 7' height and around 2-4 feet immediately to my right. For the later evening shots with low light, the flash was placed at 7' perpendicular to the railing around 20' away. In both instances, once I knew the appropriate exposure, then I could move around AND THE EXPOSURE WON'T CHANGE because the distance of the light to the subject doesn't change. So I can move around the model a bit, look for the right kind of light angle because of course the direction of light is the same and the model either turns into or turns away from the light, and I can see that effect as I shoot so I'm modelling the light. You can tell where I am and where the light is in relationship to the railing. The models are all in about the same position (apart from the first one) and I just move the light to where I want it. One fun thing about the setup is to get more light I can also just move the stand closer to the model, or to get more of a fill effect than a key light effect, I move it back, while keeping output the same. TTL will then work just to balance the light.
I was shooting in high-speed sync mode on the D800. This means when I shoot in manual, I can adjust the shutter speed for a given aperture (which I tried to keep reasonably wide for softer bokeh) in order to get the correct exposure. The flash is set up for TTL and the secret is to override the flash output because invariably it looks like flash then. I tried to reduce output until I got what looked like an ambient light effect with the flash, which you see more in the earlier evening photos. The light hitting their faces is flash because the sun is actually behind them setting toward the right (down the river). I set the flash to around -2 and 2/3 less. I also underexpose the exposure on the camera, usually -0.7 to -1.0. I have many examples where the flash was a bit too noticeable and powerful. The fun part of this setup is all I have to do to darken the background and intentionally bring out the flash is use faster shutter speeds (shorten exposure time). Earlier in the evening I was shooting 200 ISO, then when the sun went down it was 400 ISO.
To get the moon in the frame, I had to go on the ground shooting up to the model, and I'm 20' back with the light stand about 2 ft to my left. When the model looks up, she looks up towards the light, making it seem almost like moonlight or other ambient light. But it is flash that illuminates the models entirely in the later evening shots. As it got dark, I had to open up the aperture a bit. During the course of the evening, I started out shooting around 1/250th a second, then when I needed to get more of the light from the city in the background, I went down to 1/40th of a second, shooting with the 85 mm (!!). So that's handheld and the challenge was that if the model moves, there's so little light from the flash that the movement can be seen as well, like a double image. So there are many shots that didn't turn out because of that model movement.
Whew! I think that covers most of it....