Exporting Navico AT5 Maps

See also Exporting Preset Map Styles.


The AT5 Map Format

The AT5 map format is a Lowrance map format supported by a wide range of Lowrance GPS devices, from the older LMS range right through to the most recent HDS touch.

The AT5 format is able to combine vector layers, such as contour lines, with raster (image) layers. In the example below, shown on an HDS 10 unit, a coloured raster background has been combined with vector layers for the major and minor contours and land.


Shaded relief AT5 map shown on a Lowrance HDS 10. Image courtesy of AnglingCharts.com


The styling options for AT5 maps are virtually limitless. User maps provide near WYSIWYG (what you see is what you get) editing facilities; isobaths and contours can by coloured and styled, and custom paths and polygons added.


Generating AT5 Maps: The Insight Map Creator

AT5 maps are created using the Insight Map Creator tool from Navico. This tool is free, and can be downloaded from the Navico Insight Store, on the Insight Planner tab.


ReefMaster can generate the required IMC project file and run the IMC automatically during map exports. In order to do this, the location of the InsightMapCreator.exe executable file must be provided to ReefMaster using the Locate IMC option in the Global Settings. ReefMaster is compatible only with IMC versions 0.6.6 and later.


Raster versus Vector

AT5 maps can display a combination of raster and vector components. For example, in the image at the top of this page, contour and shoreline vector components have been overlaid on a coloured raster that indicates depth values. Depth colours can also be provided by vector isobath components, which are filled polygons that cover a defined depth range (e.g 0 - 5m). Vector are smaller in file size, and display-qualities that do not deteriorate as the map is zoomed.


Vector depth colours on a Lowrance HDS 5


When exporting AT5 maps, ReefMaster determines automatically whether a raster background is required.


Exporting a map with a raster or shaded relief background

Only map projects can be exported as an AT5 map with a coloured raster background. Since user maps do not store a background raster, user maps are always exported as vector maps.


Raster backgrounds are only compatible with more recent Navico units (Elite HDI units, all HDS generations). Maps for older units such as LMS and LMX should be exported as vector maps.


To export a map project with a raster background, generate a map project and ensure that the Colour Mode of the project is set to Raster. Choose the option Write to File from the Contour View.



Select AT5 as the export format, and, if also exporting waypoints, configure the Waypoints options as required.

To use a Shaded Relief raster, check the Export Shaded Relief option (1). Shaded relief can use colour bands or a gradient. Check Shaded Relief Colour Bands to use colour bands. If this option is not checked, then gradient is used (see Exporting Map Projects for more information about shaded relief).

Atlas version (2) should be left at the default value of 12 when exporting to units that support background rasters.

Click Save, at the bottom of the Export File Window.

ReefMaster copies all of the resulting AT5 files into the correct directory structure for use in a memory card on a Navico unit. To write the files directly to a memory card, insert an SD card into your computer's card reader, and select the root folder of this card as the output directory in the save file window. Note that any existing AT5 map files will be overwritten.

The IMC will be launched, and the raster and vector layers created for the map. Note that this process may take some time. You can observe the progress of the operation by clicking on the IMC icon in the Windows task bar, which brings the IMC application to the front of the screen.


Vector and raster files are written to the files at5.xml, Large.at5  and a folder ShadedRelief. These files should be located at the root of a memory card, and inserted into a GPS device.


In order to see AT5 maps on your Navico device, you must select the option Settings/Chart/Chart data/Lowrance.

To see the raster background, select the option Chart options/Imagery/Shaded relief.


Exporting a map with vector background colours (isobaths)

Maps with vector depth colours (isobaths), or no depth colours at all (just contour lines), can be exported from either the map project or a user map.


Exporting directly from a map project is a very easy way to generate maps for a Navico device, although the styling options are limited to a choice of palettes for depth and hardness areas (where applicable).


A user map gives a wide range of custom options for map styles, including the ability to choose colours for any individual area(s), add custom lines or polygons, and add tracks to the finished map, as well as use more advanced AT5 styling options such as transparency. For example, highlighting a certain depth can be easily accomplished by using a user map.


Map Projects


To include isobaths in the exported map, ensure that the map project Colour Mode is set to Vector. Regenerate the map if necessary, to create the required isobaths.

Set the palette of the map to an AT5 compatible palette. If exporting hardness areas, ensure that the hardness palette is also set to an AT5 compatible palette.

Select the option Write to File from the Contour View right-button menu.


User Maps

User maps can be exported using the Write to File option, either from the asset library or the user map right-click menu.

User maps are exported as vector components, using the styles that have been assigned within the map.


Vector Export Options

Additional options are available when exporting vector isobaths and/or hardness areas:



If the map is being exported from a map project, and the selected palette is not AT5 compatible (for either depth or hardness), then a pair of palette selector controls are shown (2). Select the required palette(s) before exporting the map. Note that this option is not shown when exporting from a user map or when exporting from a map project that already has AT5 palette(s) selected.


(1) Add depth highlight layer

A depth highlight layer enables depth-ranges to be highlighted in the selected colour. Any depth range or combination of depth ranges can be highlighted by configuring chart categories on the unit, giving the ability to change the highlighted range whilst on the water.


To add a depth highlight layer to the map, check the option Add depth highlight layer and select a colour for the layer from the drop-down list.


Using the depth highlight layer

The depth highlight layer works by creating an extra set of isobaths that are all set to a single, configurable colour, and layered underneath the existing depth map. Individual depth ranges can be highlighted in the selected colour by de-selecting the category for the required depth range in the minor category  section of the Depth Area chart category. Hiding the standard depth area in this way allows the highlight layer to be seen, whilst also being hidden by default.


With the map loaded onto the target unit, select the menu option Chart options/Categories:




Deselect the depth range that you wish the highlight in the category (Area) Depth Area. Deselecting a depth range allows the depth highlight layer, which is underneath the depth areas, to be seen:



The depth for the selected range is now shown in the depth highlight layer colour. Any combination of depth ranges can be highlighted in this way.



(3) Atlas Version

The Atlas Version is refers to the version of the finished AT5 map. Later versions of AT5 offer more features, but are not always compatible with older units. The default version is 12, which is compatible with HDS and Elite HDI models (and later). When exporting for older units, Atlas version 10 might be required; select this using the drop-down list-box.


Exporting user maps with opacity

Using varying opacity in depth and hardness areas is an easy way to create looking maps, but it is important to be aware of of a few issues when exporting maps that use opacity as AT5 maps:


Due to a quirk of the AT5 format, opacity only gets applied to vector shapes that are rendered on top of a raster layer. This means that a raster layer is required in the finished AT5 map, and that the Imagery option within the unit must be set to ShadedRelief.


ReefMaster works around this limitation by exporting a "dummy" raster layer behind the vector map. This "dummy" raster is simply a blank rectangle, rendered in the standard Navico shore colour, and is created and exported automatically if the map to be exported contains any components with transparency.


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