Occasionally, students will pull out an image they shot and ask what I think about the exposure-is it too light, too dark, or just right. I’ll study the photo for a few moments and then ask what their opinion is. I do this so we can take a deeper dive into the question, since it’s usually not something that can be easily answered.
There are issues to consider when determining what a photograph’s appropriate exposure should be. Perhaps most critical is to avoid very bright or very dark areas in the image that may cause clipping, since that can cause problems for the monitor displaying the picture or for the printer printing it.
After that, and similar to other compositional elements such as framing, camera angle, focal length, depth-of-field, etc, the photographer must determine how a specific exposure will impact the look of the photo. I would assume that most photographers strive for a “normally” or “properly” exposed image most of the time. But intentionally over-exposing or under-exposing can create a very different dynamic that often produces a more interesting and exciting image. The photos below, hopefully, will help illustrate this.
The first set of images below shows a college cafeteria. Keep in mind that the outside illumination is significantly brighter than the inside lighting. Photo 1 has been exposed for the outdoor lighting, making the greenery easily recognizable. This keeps the indoor lighting dark, but in a positive way. The reflections on the tables subtly highlight them, providing just enough illumination to render their shapes pleasingly. The more brightly exposed photo 2 shows those same interesting reflections, but with greater intensity. And though still rather dark, the cafeteria can be seen in more detail than in photo 1. In addition, the windows become grossly overexposed with the increased exposure, hiding what is outside and causing a wonderful eerie glow.
The second set of images was taken in a college classroom. I was drawn to the chairs’ tight, perfect alignment, as well as the starkness of the surroundings. For me, the precision of this scene is both inviting and off-putting.
Dark objects, like these chairs, can open up interesting lighting possibilities. That’s because they can be photographed at a variety of brighter exposures without becoming overexposed. The first picture shows the chairs and room normally exposed. This is how the room would appear to someone standing within. The second photograph is overexposed. That’s apparent when looking at the ceiling, walls, and floor. But, again, because the chairs are made from such dark material, we’re now able to see them in much greater detail. In addition, the chairs are pleasingly framed by the bright areas of the room.
Barring technical problems caused by the lighting, it’s impossible to say which exposure is correct or which is preferable. That decision is solely within the realm of the viewer and the photographer. I don’t find one picture preferable to another. I think each one offers a different but equally interesting interpretation.