According to variation theory, it is essential to enable students to focus on the object of learning and discern its critical features, but the features that "it is possible" to discern often depend on the equipment used. Thus, in labs, the experimental technologies used may shape students' experience of focal phenomena, in a "human-mediating tools-world" manner, by placing some aspects of reality in the foreground, others in the background, and visualizing certain aspects that would otherwise be invisible. However, this mediating role is often neglected, and instruments and devices are often seen as having little cognitive value. Hence, the role of experimental technologies in labs as tools for learning is examined here through a case study, in which three sets of students investigated the same physical relationships (Newtonian motion in an inclined plane), but using different measurement technologies. The results demonstrate that what it is "possible" for students to experience in a laboratory is heavily influenced by the chosen technology. Some technologies do not afford the discernment of features regarded as crucial for students to learn. Furthermore, analysis of video recordings shows that the three sets of students' discourses differed, although they studied the "same physics." Hence, the role of experimental technologies in students' learning in labs should not be neglected, and their courses of action should be seen as material-discursive practice. Moreover, general conclusions about learning in labs should be drawn cautiously, specifying the conditions and technology used, and discussions about learning technologies should not be limited to the use of computers.