OSTC dive log: Heinrichs Weikamp OSTC 4, OSTC 5, Plus and Sport dives in one logbook

Updated October 19, 2026

BubbleJournal downloads from Heinrichs Weikamp's Bluetooth OSTCs and reads the dives OSTCTools saves, so your dives can sit beside the ones from any other computer you have dived with, on the web and on your phone.

Over Bluetooth, from the app

The app is coming soon to the App Store and Google Play. Until then, bring the dives in from a file.

Turn on the computer's Bluetooth from its menu, tap Download dives in the app and choose it.

• Heinrichs Weikamp OSTC 5
• Heinrichs Weikamp OSTC 4
• Heinrichs Weikamp OSTC Plus
• Heinrichs Weikamp OSTC 2
• Heinrichs Weikamp OSTC 2 TR
• Heinrichs Weikamp OSTC Sport

From a file

Save the dives from Heinrichs Weikamp's software, then choose the files on the Import page, many at once or as a zip.

• OSTCTools, one dive per file: .dive

What comes across

• The depth profile and water temperature
• Gases, with oxygen and helium, and the switches between them
• The computer's own NDL and stops, and CNS
• On a rebreather: the setpoint and the loop oxygen

Every file you import is kept exactly as uploaded, so nothing is lost if BubbleJournal learns to read more of it later.

What doesn't

• The first OSTCs (Mk.2, 2N, 2C), the OSTC 3 and the OSTC cR connect only by cable, and the Frog only by classic Bluetooth, which the app doesn't speak: save their dives with OSTCTools instead.
• Logs from an OSTC 3 or later name no model, so dives imported from OSTCTools files show the computer as Heinrichs Weikamp, with its serial number.

Its decompression model

OSTCs use Bühlmann ZHL-16 with gradient factors, and the OSTC 4 and 5 also offer VPM-B. Where the file holds it, the computer's own NDL comes across with each dive. BubbleJournal also works the NDL and tissue loading out again with one model, Bühlmann ZHL-16C, so dives from any computer can be compared: why your computer and your logbook disagree.

What the numbers mean

• Air consumption (SAC rate): how to work it out and use it
• No-decompression limit (NDL): what it is and why it changes
• Tissue loading: what the percentage means and how it falls
• How to read a dive profile

Other dive computers · Keep your Heinrichs Weikamp dives in BubbleJournal, free