Abstract Microgenetic methodologies developed in the firsthalf of the twentieth century are still used in some perception studies. However, contemporary microgenetic studies do not always share the original theoretical background that originated concept definition. Particularly, the phenomenological background of concept has been neglected. This paper shows an ideographic study that aims understanding the perception of emotional faces phenomenon from a microgenetic point of view. We recorded the response of participants viewing pictures of faces exposed for a very brief time. We observed that persons feel emotional tension when they don't know exactly what is in the picture. This emotional tension motivated participants to construct a more stable meaning of the forming percept. Additionally, we observed two types of answers, suggesting two perceptual experiences. One answer was preconceptual, descriptive and restricted to image details, presenting different verbalizations and corporal actions with the second, where the subjects inferred upon what they saw from the images.