A collection of raw water temperature-depth-time profiles were recorded from a selection of dive computers, underwater cameras and baseline Castaway microCTD devices. Data were collected at Oban recompression chamber (owned and managed by Tritonia Scientific), as well as during sea dives local to 56.42 N, 5.47W, over a two-week period between 08/01/2020 and 07/02/2020. A number of different devices and models were tested during the study. Chamber dives were undertaken to test and compare device response time (29 devices over 11 dives) and accuracy (6 replicate dives). This was followed by local sea dives to further compare device accuracy. During each pair of sea dives (6 total), half of the devices were mounted on a frame with the remainder worn by two divers. For the subsequent dives in each pair, each device was switched to the alternate mounting position. Dive profiles were exported from individual dive computers into Subsurface open source software, then exported in ssrf (XML) format for each week of data collection. Profiles from all dive computers were combined for analysis. Castaway microCTDs and Paralenz Dive Camera+ profiles were exported as individual CSV files per dive. Data were collected as part of Celia Marlowe’s PhD project at the University of East Anglia, which aimed to assess the precision, accuracy and uncertainty in water temperature profiles collected from devices commonly carried by Scuba divers. The PhD project is part of the Next Generation Unmanned Systems Science (NEXUSS) Centre for Doctoral Training, funded by the Natural Environment Research Council (NERC) and the Engineering and Physical Science Research Council (EPSRC) (NE/N012070/1), and is additionally supported by Cefas Seedcorn (DP901D). The diving and chamber tests were supported through a NERC National Facility for Scientific Diving grant (NFSD/17/02).