Individual S/N maps for the five 2018 epochs. From left to right, top row: MJD 58 222, 58 227, 58 244; bottom row: 58 257, 58 288. The candidate counterpart of Proxima c is circled. Some bright background sources not subtracted from the individual images are shown. However, these move rapidly because of the large proper motion of Proxima, so they are not as clear in the median image of Fig. 1. The color bar is the S/N. S/N detection is at S∕N = 2.2 (MJD 58 222), 3.4 (MJD 58 227), 5.9 (MJD 58 244), 1.2 (MJD = 58 257), and 4.1 (MJD 58 288).