I-band time-series observations of five bright ultracool dwarfs

Seventy hours of charge‐coupled device photometry of four L dwarfs and one T dwarf are described. Observations of three of the L dwarfs showed good evidence for variability: periods of 6.9, 2.9 and 3.1 h were tentatively identified in the observations of 2M 0451−3402, SSSPM 0829−1309 and 2M 0835−0819, respectively.