: CM93 v2 charts are outdated . C-MAP ceased official updates for the v2 format years ago in favor of newer, encrypted versions. They should be used for situational awareness and planning, but not as your primary means of navigation in restricted waters where recent hydrographic changes (like shifted sandbars or new buoys) are critical.
CM93 v2 charts remain one of the most widely used formats for marine electronic navigation, particularly among cruising sailors, long-distance voyagers, and users of open-source plotting software like OpenCPN. As a comprehensive vector chart dataset covering the entire globe, they offer immense value for navigation.
If you possess a legitimate copy of CM93 charts ( cm93 v2 charts download
Unlike raster charts (which are simple scanned images of paper charts), vector charts like CM93 v2 contain intelligent data: depth contours, buoys, lights, port services, and tide information stored as objects. This allows navigation software to:
OpenCPN will take a moment to scan the charts. You can then toggle "Chart Outlines" to see the coverage areas, which are divided into 40° × 40° squares. Ensure "Chart Quilting" is enabled to seamlessly blend different chart scales. Best Practices and Tips for Using CM93 Charts : CM93 v2 charts are outdated
CM93 v2 charts are a legacy format of unencrypted vector nautical charts originally produced by C-MAP. They are highly popular in the cruising community because they provide worldwide coverage and are compatible with open-source navigation software like OpenCPN .
I can provide step-by-step instructions tailored exactly to your onboard electronics layout. Share public link CM93 v2 charts remain one of the most
: A single database covers all major oceans, seas, and navigable waterways.
Updating CM93 v2 charts was not a simple patch process. To apply updates, users had to load an entirely new, complete set of charts. This made keeping charts current a cumbersome process, and it's a primary reason why most circulated copies are significantly out of date.
The complete CM93 v2 world set is quite large. In compressed form, it can be 4GB or more. When extracted, the full folder structure contains tens of thousands of files totaling many gigabytes. Be prepared to allocate significant storage space, especially if you plan to store the entire world set on a device like a Raspberry Pi or onboard laptop.