I tend towards the George Gruell approach - nighttime shots are best shown when it's extremely dark - very dark blue (almost black) or black sky. And unilluminated areas either not at all visible or just barely perceptable.
The supreme challange is to recreate the viewer's actual experience on the property late at night. That's the starting point. That's when you should take your shots.
When I started taking landscape lighting photos, I tried finding that perfect time just after sunset when you can start to see the lighting effects but could still get details in the unilluminated areas. But the results were always too bright.
Then, as I upgraded to a good digital camera, I found I could capture details in unilluminated areas even late at night. Now I start my shoots 1 to 2 hours after sunset.
The challenge of course is the live viewer can (in a single glance) see details in lit areas (about 0.1 fc to 5 fc) and unlit areas (about .001 to .01 fc). That's a remarkable contrast ratio (more accurately, dynamic range) up to about 1:1000. Think of this as 1,000 little boxes of different levels of brightness or color - the human can detect each of them as different. And, if you take into account that our eye quickly adjusts to varying levels of brightness, then the number increases exponentially.
Compare this to digital cameras. Since they record images as pixels (little boxes of color) they are limited in their dynamic range (at one exposure setting) to 1:255 because there are only 255 different colors (in the RGB spectrum) to choose from. That means to fully capture all the details in a nightime scene with your camera (to reproduce what the eye sees), you would need to take pictures at many exposure settings - so that 255 gets multiplied many times - getting closer to the 1,000 boxes seen by the human eye.
This is what must be done if you really want to reproduce what the eye sees, and not just produce a photo that goes to black in the shadows. Multiple exposures combined in Photoshop will produce a single beautiful image.
Of course, the task is easier if your lighting is less bright (closer in brightness to unilluminated areas).
I know, way too much information! Bottom line, take photos late at night. Set you first exposure to an illuminated area, then bracket up (increase F-stop) one stop at a time until you can see details in the shadowed areas. Also bracket down 1 or 2 stops because you may want the illuminated area less bright.
If you can't use photoshop to combine the different exposures, just use the one that looks best.
By the way, for best results (use lowest possible ASA (ISO) - usually 100), and F-stop at F11 or F16. Best to bracket by changing shutter speed rather than F-stop. And, of course, use a tripod!
Communication and Marketing Director
CAST Lighting LLC.