Navigation General · Electronic Nav — ENC vs RNC
An Electronic Navigational Chart (ENC) differs from a Raster Navigational Chart (RNC) in that an ENC is:
- AA scanned photo of a paper chart
- BA vector, object-oriented database (S-57) that supports alarms and interrogation✓ Correct
- COnly usable on paper
- DLower in accuracy
Explanation
An ENC is vector data built to the IHO S-57 standard: each feature is an intelligent object, so ECDIS can interrogate items, set safety contours, and trigger alarms. An RNC is a raster (pixel) scan of a paper chart with no underlying intelligence.
Authority: IHO S-57; SOLAS V/19
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