Budding photographers, beware: the beauty of a serene sunset, a peaceful forest or a majestic mountain range is not sufficient to make a vacation snapshot memorable. In fact, pleasing images of landscapes or forests are often the hardest to recognize and remember later on, according to a study presented at the IEEE Conference on Computer Vision and Pattern Recognition in June.

Long thought to be too subjective to define, the properties that make a photo memorable actually remain largely constant from one person to the next, the study found. Researchers showed study participants hundreds of photos, some of which were repeated; pictures that the volunteers recognized as something they had seen before were considered the most memorable.

Using this method, researchers found that an attractive image is not more likely to be recognized. Rather “mem­orability seems more related to strangeness, funniness or interestingness,” says Phillip Isola, a graduate student at the Massachusetts Institute of Technology and a lead researcher on the study.

Having people in the picture—even if they are strangers—also help make a photo more memorable, as does the impli­cation of movement, such as a person running or waves crashing. Human-scale objects—chairs and cars rather than valleys and planets—similarly plant themselves in our mind. These observations support the evolutionary theory that our brain is wired to notice movement, other people and objects we can interact with, the researchers say, because these things would have been the most important features of the landscape we evolved in.

Still, scenes that lack these attributes are not doomed to be forgotten. Simple changes can increase their mem­orability, such as the presence of a tiny hiker in the back­ground of a mountainous panorama. So the next time you’re out to take a memorable shot, make it interesting—not just pretty.