C-MAP REVEAL Large on SD / microSD Card – Complete Guide

Introduction

The C-MAP REVEAL Large on SD / microSD card is digital marine charting designed for coastal and regional navigation with a marine GPS, chartplotter or navigation system compatible with C-MAP charts.

The C-MAP REVEAL range is distinguished by a particularly detailed representation of the marine environment. Depending on the area and chart reference, it can include depth data, soundings, bathymetric contours, shaded relief, high-resolution bathymetry, satellite or aerial imagery, as well as detailed plans of ports and marinas.

The Large designation corresponds to a broader geographical coverage category than some more targeted coverage options. It can be suitable for navigators who want chart coverage over a relatively large sailing area, for example for coastal cruises involving several ports, islands or navigation areas.

However, the coverage level indicated by Large should always be distinguished from the actual geographical area covered. The exact coverage always depends on the specific C-MAP chart reference.

What is a C-MAP REVEAL Large chart?

A C-MAP REVEAL Large is a digital marine chart from the C-MAP REVEAL range, supplied on an SD or microSD card depending on the reference.

It allows a compatible navigation device to display a digital representation of the covered marine area.

Depending on the available data, the chart may include:

• coastlines and islands;

• depths and soundings;

• bathymetric contours;

• channels and navigable passages;

• ports and marinas;

• navigation aids;

• charted hazards;

• selected special or regulated areas;

• detailed port plans;

• high-resolution bathymetry;

• underwater relief displayed using shaded relief.

The availability and level of detail of this information may vary depending on the region. The exact chart reference is therefore essential for determining the data actually available.

What does “Large” mean in C-MAP REVEAL?

The term Large refers to a broader geographical coverage category than Medium or Local coverage where these options are available within the same product family.

However, Large should not be considered a universal geographical definition. A C-MAP REVEAL Large chart does not automatically cover an entire continent, ocean, sea or the world.

Coverage depends on the cartographic area defined by C-MAP for each specific reference.

This distinction is important for navigators. Someone who regularly undertakes coastal passages over several hundred nautical miles may prefer broader chart coverage in order to avoid changing chart areas when moving from one region to another.

The choice should therefore be based on the actual navigation area, rather than solely on the terms Medium, Large or any other coverage category.

Charting for extended coastal navigation

A C-MAP REVEAL Large chart can be particularly suitable for coastal navigation covering several different areas.

For example, a sailing yacht undertaking a cruise lasting several weeks may visit several ports, islands, bays and different coastal areas.

Broader geographical coverage makes it possible to maintain consistent chart coverage over a significant part of the route.

The navigator can therefore:

• plan a route involving several stages;

• identify ports and marinas along the route;

• set waypoints;

• examine charted depths;

• analyse coastal passages;

• prepare several stopover options;

• adapt the route to navigation conditions.

Detailed underwater relief representation

One of the main advantages of the C-MAP REVEAL range is its graphical representation of the seabed.

Shaded relief makes it possible to visualise variations in underwater terrain through a graphical representation.

This adds another dimension to digital marine chart reading. The navigator does not only have numerical depth values but can also visualise the general shape of the underwater terrain.

Where high-resolution bathymetric data are available, they can provide an even more detailed representation of selected areas.

This information can be useful for understanding the configuration of a bay, underwater plateau, rocky area or sector with significant changes in depth.

Depths and bathymetric data

A C-MAP REVEAL Large chart can display soundings, depths and bathymetric contours depending on the charted area.

These data are particularly important when planning a coastal route.

They can, for example, help identify areas where depths gradually decrease, visualise changes in bathymetry or identify charted channels.

However, it is essential to distinguish charted depth from the actual depth measured beneath the vessel.

Digital marine charting uses hydrographic data incorporated into the chart. The vessel's echo sounder, on the other hand, measures the instantaneous depth beneath the hull.

The navigator should also take into account:

• vessel draught;

• tides;

• water-level variations;

• swell;

• currents;

• local conditions.

Ports, marinas and approaches

Broader coverage is particularly useful when a navigator plans several stopovers.

Depending on the area and available data, C-MAP REVEAL may provide detailed plans of ports and marinas.

During a coastal cruise, the navigator can therefore examine several potential stopover options in succession.

Before entering a port, the navigator can move from a general view to a more detailed representation in order to study the approach and the available chart information.

This can be particularly useful when the route needs to remain flexible.

For example, a navigator may have a primary stopover planned while keeping several alternative ports available. Sufficiently broad chart coverage makes it possible to work with these different options without changing the charted area.

Satellite imagery and aerial photography

Depending on the chart reference and geographical area, C-MAP REVEAL charts may also provide satellite imagery or aerial photography.

These representations complement conventional marine charting by providing a visual view of selected coastal areas.

They can be used to:

• better visualise a coastline;

• understand the configuration of an island;

• examine selected harbour areas;

• complement interpretation of the marine chart;

• prepare a stopover.

The availability of imagery and its level of detail nevertheless depend on the covered area.

Example: a multi-region coastal cruise

Imagine a vessel undertaking a coastal cruise lasting several weeks.

The navigator can begin by planning a general route connecting several ports. Different waypoints can then be established and the coastal areas along the route examined.

For each stage, the navigator can study:

• the coastline configuration;

• depths;

• bathymetric contours;

• channels;

• charted hazards;

• navigation aids;

• ports and marinas.

As a stopover approaches, the navigator can increase the chart detail to prepare the harbour approach.

The ability to maintain relatively broad geographical coverage can be particularly useful for this type of navigation.

C-MAP REVEAL Large on SD or microSD card

The charting is supplied on an SD or microSD card, depending on the reference.

However, the physical storage format alone does not guarantee compatibility with a navigation device.

Before use, it is important to check:

• the GPS or chartplotter brand;

• the exact model;

• compatibility with C-MAP;

• the specific chart reference;

• the geographical area covered;

• the SD or microSD format;

• the equipment's software or firmware version where required.

A C-MAP microSD card is therefore not simply a memory card containing standard files. It is designed for use with compatible navigation equipment and systems.

For sailing yachts and motorboats

The C-MAP REVEAL Large can be used on sailing yachts or motorboats equipped with a compatible navigation system.

On a sailing yacht, it can support coastal cruises involving several stages and help plan different sections of a route.

On a motorboat, it can be used for coastal passages, journeys between ports and regional navigation.

In both cases, chart information must be interpreted in relation to the vessel's characteristics and navigation conditions.

Digital charting does not replace official nautical information

Even highly detailed digital charting does not constitute all the information required for navigation.

Navigators should continue to consult official nautical information, navigational warnings, local regulations, port information and weather forecasts.

A digital chart should also not be considered a real-time measurement of the underwater environment.

The echo sounder, visual observation, up-to-date nautical information and the navigator's experience remain complementary to electronic charting.

How to choose a C-MAP REVEAL Large chart

The choice should begin with the intended navigation area.

The exact coverage of the C-MAP REVEAL Large reference being considered should then be checked.

The main criteria are:

• geographical area;

• exact C-MAP reference;

• coverage extent;

• GPS or chartplotter model;

• C-MAP compatibility;

• SD or microSD format;

• features available in the relevant area;

• available update options.

A C-MAP REVEAL Large chart is therefore not necessarily a worldwide chart or a chart covering an entire sea or country. The Large designation must always be considered together with the exact chart reference and its coverage area.

Conclusion

The C-MAP REVEAL Large on SD / microSD card is digital marine charting designed for navigators looking for broader geographical coverage for coastal or regional navigation.

It benefits from the features of the REVEAL range, including detailed underwater relief representation with shaded relief, high-resolution bathymetric data in selected areas and, depending on the reference, satellite imagery, aerial photography and detailed plans of ports and marinas.

It is particularly useful for navigation involving several stages and different coastal areas. The key consideration remains to match the navigation area, the exact chart reference and the GPS or chartplotter model.

FAQ – C-MAP REVEAL Large on SD / microSD Card

What is a C-MAP REVEAL Large chart?

It is digital marine charting from the C-MAP REVEAL range offering broader geographical coverage than some more targeted coverage options, depending on the available references.

What does “Large” mean in C-MAP REVEAL?

Large identifies a geographical coverage category. The exact area covered always depends on the specific C-MAP chart reference.

Does a C-MAP REVEAL Large chart cover an entire sea or ocean?

Not necessarily. The term Large does not automatically mean worldwide, ocean-wide or complete coverage of an entire sea. The exact coverage of the specific reference must be checked.

What is a C-MAP REVEAL Large chart used for?

It allows digital marine charting to be displayed on a compatible GPS or chartplotter, routes to be planned, waypoints to be set and available information within the covered area to be viewed.

Does C-MAP REVEAL Large display depths?

Yes. Depending on the area, it can display soundings, depths and bathymetric contours.

Does C-MAP REVEAL Large display underwater relief?

The REVEAL range provides features such as shaded relief and, in selected areas, high-resolution bathymetric data to provide a clearer representation of underwater terrain.

Are C-MAP depths measured in real time?

No. The displayed depths correspond to the chart data. The vessel's echo sounder provides the instantaneous depth measurement beneath the hull.

Does C-MAP REVEAL Large provide port and marina information?

Depending on the reference and area, it can provide detailed plans of ports and marinas.

Does C-MAP REVEAL Large provide satellite imagery?

Depending on the area and reference, some REVEAL charts may include satellite imagery or aerial photography.

Does a C-MAP REVEAL Large chart work with all marine GPS units?

No. The GPS or chartplotter must be compatible with C-MAP and with the specific chart reference.

Will a C-MAP REVEAL Large card work in any microSD reader?

No. The presence of a microSD card slot does not guarantee compatibility. The navigation equipment must support the relevant C-MAP chart.

Is C-MAP REVEAL Large suitable for sailing yachts?

Yes, provided the equipment is compatible. It can be particularly useful for coastal cruises involving several stages.

Is C-MAP REVEAL Large suitable for motorboats?

Yes. It can support coastal and regional navigation on a motorboat equipped with a compatible navigation system.

What area does a C-MAP REVEAL Large chart cover?

The exact coverage depends on the specific chart reference. The term Large alone does not identify a precise geographical area.

How do I choose the correct C-MAP REVEAL Large chart?

Check the intended navigation area, exact chart reference, geographical coverage, GPS or chartplotter model, C-MAP compatibility and SD or microSD format.

Does a C-MAP REVEAL Large chart replace official nautical information?

No. It is an electronic navigation aid and should be used together with official nautical information, navigational warnings, local regulations and available weather information.