Shortly after the Transatlantic Exoplanet Survey discovered a hot Jupiter (TRES-1B) transiting the K0V dwarf GSC 02652-01324 in 2004, the RCT was used to observe a transit, as shown in the diagram shown here. Scatter increased markedly over the time of observation as the airmass became large — typical transit observations at normal airmass will resemble the left side of the diagram.

The RCT is capable of detecting such transits reliably at least to the millimag level.