Bambu Studio to OrcaSlicer

OrcaSlicer is a fork of Bambu Studio and writes the same files with the same names, so this pair is the easy one. Converting is about the profile, not the format.

Does OrcaSlicer need the file converted at all?

Not to open it. The mesh, every plate, the filaments, the modifiers, the part settings and the paint all arrive as they were. OrcaSlicer may warn that some settings differ from its own.

Then what does converting change?

The printer, process and filament presets become OrcaSlicer's, aimed at the machine you pick. Tick Slicer on its own and every value your file already had stays put.

Which OrcaSlicer settings will be empty?

The several hundred settings OrcaSlicer added after the fork, among them adaptive_pressure_advance, input shaping, bed mesh probing and brim ears. A Bambu Studio project holds no value for any of them, so they open at OrcaSlicer's defaults.

Do my filaments and their nozzle map carry?

Every filament does. A map that sends a filament to a named nozzle only lands on a printer with as many nozzles, so check it if the OrcaSlicer machine you pick has fewer. See what a conversion cannot carry.

Is it the same going back?

No. Bambu Studio has no field for those extra settings, so the reverse trip loses them. See OrcaSlicer to Bambu Studio.