The design and construction of HiPERCAM was funded by the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) under ERC-2013-ADG Grant Agreement no. 340040 (HiPERCAM). VSD, ULTRACAM and HiPERCAM operations are funded by the Science and Technology Facilities Council (grant ST/V000853/1). RPB, CJC, DMS, MRK and GV acknowledge support from the ERC under the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 715051 (Spiders). MRK acknowledges support from the Irish Research Council in the form of a Government of Ireland Postdoctoral Fellowship (GOIPD/2021/670: Invisible Monsters). DMS acknowledges the Fondo Europeo de Desarrollo Regional (FEDER) and the Canary Islands government for the financial support received in the form of grant number PROID2020010104. SGP acknowledges the support of a STFC Ernest Rutherford Fellowship. IP and TRM acknowledge support from the UK's Science and Technology Facilities Council (STFC), grant ST/T000406/1. The GTC is installed at the Spanish Observatorio del Roque de los Muchachos (ORM) of the Instituto de Astrofisica de Canarias (IAC), on the island of La Palma. The WHT is operated on La Palma by the Isaac Newton Group in the Spanish ORM of the IAC.

Optical observations of PSR J2051-0827 taken by the high-speed triple-beam CCD camera ULTRACAM on the William Herschel Telescope, and by the high-speed quintuple-beam CCD camera HiPERCAM on the Gran Telescopio Canarias. As presented in Dhillon et al. 2022 (MNRAS, in press, https://arxiv.org/abs/2208.09249). The letter after the underscore in each file name represents the observing filter for that specific file. For the ULTRACAM data, the columns are: 1) orbital phase (in rotations, with phase = 0 corresponding to pulsar's ascending node), 2) flux density (in erg cm-2 s-1 Hz-1) 3) flux density uncertainty (in erg cm-2 s-1 Hz-1) For the HiPERCAM data, the columns are: 1) MJD time 2) orbital phase (in rotations, with phase = 0 corresponding to pulsar's ascending node), 3) flux density (in erg cm-2 s-1 Hz-1) 4) flux density uncertainty (in erg cm-2 s-1 Hz-1)