There are many ways to shoot architectural photography, some of which include ambient light only, on-camera flash and of coarse off-camera flash with usually more than one flash or strobes with modifiers. The way I prefer to do it when I have the time and I want an image that no other method can deliver is exposure blending. This method requires a base exposure shot and then you use that image to stack onto it the different flashed exposures and build a final image. For this shot I got an ambient exposure at .8 Sec F/8 ISO 100 and I was shooting the Nikon 14-24 F/2.8 I then took a number of exposures as I walked around flashing everything I wanted lit.
In Photoshop I stacked all the images together and with masks I just used the spotlighted parts of the image.
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