RAW or JPEG for underwater photos?
Shoot RAW when you expect large exposure or colour adjustments and your camera supports it without getting in the way. JPEG is faster, smaller and still edits well when exposure is sound; getting close and protecting highlights matter more than the file extension.
Imagine two usable photographs from the same dive: a carefully exposed JPEG from a rented action camera and an underexposed RAW frame from a larger camera. The RAW file has more room for correction, but the JPEG may still produce the better photograph. File format preserves options; it does not repair focus, distance, camera movement or clipped light.
What RAW actually preserves
A camera RAW file retains sensor measurements before the camera has committed them to a finished photograph. The RAW processor interprets white balance, colour rendering, sharpening, noise reduction and tone later, while preserving the underlying capture for another edit.[1]
RAW formats vary by camera. They are not universally uncompressed or 16-bit; many use lossless or lossy compression and different sensor bit depths. Their practical advantage is that they usually retain more tonal and colour information than the camera’s JPEG.
That extra latitude matters underwater. Strong correction can expose noise in a weak warm channel, while sun discs, bubbles and strobe-lit foregrounds can approach clipping. RAW gives the processor more information when balancing those extremes. It still cannot recover a highlight that saturated the sensor or clean colour that was never recorded above noise.[2]
What the camera has decided in a JPEG
A JPEG is already a rendered photograph. The camera has applied white balance, a colour profile, a tone curve, sharpening and noise reduction before compressing the result, normally to eight bits per channel.[1]
Those decisions are not a reason to discard the file. White balance and exposure can still be adjusted, but large changes reach banding, compression artefacts and rough colour sooner because the original sensor values are no longer available. A correctly exposed JPEG made close to the subject will usually withstand more useful editing than a hazy, clipped or blurred RAW frame.
Choose RAW for important stills, uncertain mixed light and files likely to need substantial tonal work. Choose JPEG when speed, storage or a simple action-camera workflow matters. RAW+JPEG is useful when the camera can record both without interfering with the dive.
Bring a restrained file into Five Meters
Develop a RAW file in a RAW processor first and export a full-resolution, high-quality JPEG for Five Meters. Correct clear exposure errors and protect highlights, but leave saturation, sharpening and noise reduction restrained so the underwater restoration has clean pixels to work with.
Upload an original camera JPEG rather than a social-media copy. The full-resolution original gives Five Meters the detail it needs; messaging compression throws that away before you start.
From either source, Five Meters derives a learned cross-channel colour transform instead of relying on Temperature and Tint alone. Its Dehaze control uses a spatial transmission estimate, and its Water controls use a model-derived matte—so a well-exposed rendered file still gains richer colour and clearer separation than a single white-balance move.
After restoration, inspect smooth water, shadowed gear and colour transitions at full size. Keep the original file so you can re-export a cleaner conversion if you ever want a second pass.