While I was taking pictures there one night, I had a bit of a dilemma. It was almost dark and the building with the indoor pool was beautifully reflected in the small pond encircling it. To flash or not to flash? I tried both. You may be surprised to find out that the first picture is the one
and the 2nd is without. The light wasn't able to reach the building before the shutter closed so the only thing that caught the light from the flash is the grass. For the second I leaned against a pole to hold the camera steady. With a flash on you lose most of the natural light in your shot.
Sometimes that's what you really want to show. Here's an example from Disney World's Magic Kingdom.
With the flash you see all the details of the railing and the golds and grays of the stage, but there's no way that you would know that
the archway was lit up with blue light. Without the flash you see that but can't make out the same level of details. As a photographer you have to decide which one you prefer or take both (which is what I usually do) and use both later for something like this. You know I'm always thinking of you.
With--you show the bellhop directing people to the elevator in the Tower of Terror,
or--without--you create a ghostly vision of the same scene.
With--you show the exact material of the ball at Epcot,
or--without--you emphasize how the ball glows.
With--you show how the path at Epcot is made with some paving stones that seem to sparkle,
or--without--you show how they light the path in the darkness.
When we take pictures, we are always faced with this choice (whether we realize it or not).
Application to writing? When setting a scene, we should decide what we want our description to do: give specific details of the surroundings or set a mood.