Blue Marble Geographic Calculator 2023 Build 1183

Base Coordinate Display

With many coordinate transformations or coordinate systems, the comparisons for control are made in a geodetic latitude and longitude. Often referred to as base coordinates, a transformation is completed from geodetic coordinate to geodetic coordinate, and then a projection is applied. Displaying the base geodetic coordinates alongside the projected coordinate when the selected target system is projected allows users to compare the projected with its equivalent geodetic coordinate in a lat/long representation.

Continuing a Blue Marble tradition of user-driven development, Geographic Calculator 2023 includes an option to simultaneously output both the projected and base geodetic coordinates from Interactive and Point Database jobs. Displaying the base values for both the source and target systems allows for a quick sanity check when performing conversions on systems that are sometimes difficult to conceptualize. This is especially useful when working between different coordinate systems with varying ranges of valid numeric values.


In this Interactive Conversion Job the output point is listed as projected coordinates as well as the base geodetic latitude/longitude coordinates.

Updated GeoCalc Dialogs

The GeoCalc dialogs include all of the interface dialogs used to browse, select, and edit objects in the Geographic Calculator datasource. You may have encountered these familiar interface dialogs as they were developed for the GeoCalc Software Development Kit and used in several other applications to power their geodetic operations. Maintaining a consistent look and feel of the GeoCalc dialogs has always been important. Though there is a noticeable change with this release, the new interfaces retain much of that old familiarity while improving the search and query capabilities. These dialogs interact with a geodetic datasource that has grown to encompass more than 5000 coordinate systems, 2000 transformations, and many other parameters, so these enhancements were necessary.

When we began designing the new search, we kept coming back to a common enough workflow; that of online shopping on a large storefront website. Similar to searching Geographic Calculator’s extensive datasource, you may know bits and pieces of the object you are looking for but not necessarily its exact name or even what category or regional grouping to find it.

While the longstanding folder-style view is still a primary way to navigate the datasource, the updated dialogs now contain a checkbox to view the objects in all subfolders of the selected folder, which facilitates the search. This optional expanded view, coupled with a live filter search and multi-parameter search, makes it easier to pull up a coordinate system or other geodetic definition you aren’t sure exactly how to find.


The updated GeoCalc dialogs include a live filter search, a multi-parameter search, as well as the traditional folder-based organization.

The live filter search, on the top left of the datasource browsing dialogs, dynamically updates the list of matching objects as you type in a search term. This allows you to find the item you are looking for with fewer clicks than in the past. The advanced search opens a new dialog where you can enter multiple search conditions and select the relevant geographic area through a more flexible map interface. The advanced multi-parameter search is particularly helpful when you only have partial information on a specific coordinate reference system. By entering what you do know, the search function quickly searches projections by the datum, projection, and central meridian, filters across various country’s folders, and finds the regional system you need.

Point-Specific Transformation Metadata

In recent years, a very common transformation for our American users, moving between various realizations of the North American Datum, has moved over to the new toolkit by the National Geodetic Survey (NGS) known as NADCON 5. This toolkit, supported by Geographic Calculator, is the basis of the national transformations between any realization within the National Spatial Reference System. With the advent of NADCON 5, more detailed information about transformations is now easily accessible on an individual point basis, with an impressive new capability important in high-accuracy mapping applications as we move towards future surveying technologies and coordinate systems.

In Geographic Calculator 2023, transformations involving the NADCON 5 methods report what NGS refers to as “uncertainty” of the transformation of the individual points, allowing users to assess the confidence in the output positions based on the transformation. These uncertainties reported by the NGS on the NCAT website are labeled as errors in Geographic Calculator 2023 and made available for any Interactive or Point Database NADCON 5 transformation.


Fully updated to support NADCON 5, Geographic Calculator 2023 now reports point error values in Interactive and Point Database conversions using NADCON5 methods.

In a related area, the modern GNSS-based coordinate systems are starting to provide additional metadata about points on an individual level. For time-based coordinate transformations, this includes velocities between the epochs involved. In Geographic Calculator 2023, velocity information provided by the relevant survey authorities is now available for Horizontal Time Dependent Positioning based transforms here in the United States, as well as the Canadian time-based transformations.

Preparing for future epochs

As Geographic Calculator continues to be the industry standard for precise geodetic conversion and coordinate system management, the Blue Marble development team swiftly progresses with the latest trends in geodetic science. With dynamic reference frames popping up all over the globe, it’s an exciting time to be in geodetics! We’re confident that the new features and improvements in Geographic Calculator 2023 will significantly improve our users’ workflows.