Thanks, Christina!
Anytime anyone uses negative space, it's simply a personally preferred mechanism for displaying the subject in a context that brings attention to it for whatever reason. In this case, three factors drove me to do so:
- I lit the rear area of the scene to provide a background of sorts for the tabletop's negative space. I could have instead lit that area to provide a bright area of the background only around the subject, but doing so would not have emphasized the context of the negative space or at least not in the same way in my mind.
- Allowing such a large amount of negative space allowed more room to display the interesting reflections of refracted light on the tabletop (which ironically perhaps means that there is not as much negative space as one would think).
- The position of the trap's handle suggests that the trap is facing to the left, as if it is "looking" into the negative space. Allowing anyone or any thing to look into negative space provides context that tight framing eliminates.