diff --git a/FileDbCache/UWP/FileDbCache.UWP.cs b/FileDbCache/UWP/FileDbCache.UWP.cs
index d1734265..8d7bec18 100644
--- a/FileDbCache/UWP/FileDbCache.UWP.cs
+++ b/FileDbCache/UWP/FileDbCache.UWP.cs
@@ -17,12 +17,12 @@ namespace MapControl.Caching
         {
             if (folder == null)
             {
-                throw new ArgumentNullException("The parameter folder must not be null.");
+                throw new ArgumentNullException(nameof(folder));
             }
 
             if (string.IsNullOrEmpty(fileName))
             {
-                throw new ArgumentException("The parameter fileName must not be null or empty.");
+                throw new ArgumentException("The fileName argument must not be null or empty", nameof(fileName));
             }
 
             Open(Path.Combine(folder.Path, fileName));
diff --git a/FileDbCache/WPF/FileDbCache.WPF.cs b/FileDbCache/WPF/FileDbCache.WPF.cs
index a0aa8269..3faa2d23 100644
--- a/FileDbCache/WPF/FileDbCache.WPF.cs
+++ b/FileDbCache/WPF/FileDbCache.WPF.cs
@@ -17,7 +17,7 @@ namespace MapControl.Caching
         {
             if (string.IsNullOrEmpty(path))
             {
-                throw new ArgumentException("The parameter path must not be null or empty.");
+                throw new ArgumentException("The path argument must not be null or empty.", nameof(path));
             }
 
             if (string.IsNullOrEmpty(Path.GetExtension(path)))
@@ -82,12 +82,12 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             try
             {
-                return fileDb.GetRecordByKey(key, new string[0], false) != null;
+                return fileDb.GetRecordByKey(key, Array.Empty<string>(), false) != null;
             }
             catch (Exception ex)
             {
@@ -106,7 +106,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             var record = GetRecordByKey(key);
@@ -144,12 +144,12 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             if (!(value is ImageCacheItem imageCacheItem))
             {
-                throw new ArgumentException("The parameter value must be a MapControl.Caching.ImageCacheItem instance.");
+                throw new ArgumentException("The value argument must be a MapControl.Caching.ImageCacheItem instance.", nameof(value));
             }
 
             AddOrUpdateRecord(key, imageCacheItem.Buffer, imageCacheItem.Expiration);
diff --git a/MapControl/Shared/LocationCollection.cs b/MapControl/Shared/LocationCollection.cs
index 52733042..937ac6cf 100644
--- a/MapControl/Shared/LocationCollection.cs
+++ b/MapControl/Shared/LocationCollection.cs
@@ -9,7 +9,8 @@ using System.Linq;
 namespace MapControl
 {
     /// <summary>
-    /// A collection of Locations with support for string parsing and calculation of great circle and rhumb line locations.
+    /// A collection of Locations with support for string parsing
+    /// and calculation of great circle and rhumb line locations.
     /// </summary>
 #if !WINDOWS_UWP
     [System.ComponentModel.TypeConverter(typeof(LocationCollectionConverter))]
@@ -64,7 +65,7 @@ namespace MapControl
             if (resolution <= 0d)
             {
                 throw new ArgumentOutOfRangeException(
-                    nameof(resolution), "The parameter resolution must be greater than zero.");
+                    nameof(resolution), "The resolution argument must be greater than zero.");
             }
 
             resolution *= Math.PI / 180d;
@@ -126,7 +127,7 @@ namespace MapControl
             if (resolution <= 0d)
             {
                 throw new ArgumentOutOfRangeException(
-                    nameof(resolution), "The parameter resolution must be greater than zero.");
+                    nameof(resolution), "The resolution argument must be greater than zero.");
             }
 
             resolution *= Math.PI / 180d;
@@ -139,13 +140,13 @@ namespace MapControl
             if (double.IsInfinity(y1))
             {
                 throw new ArgumentOutOfRangeException(
-                    nameof(location1), "The parameter location1 must have an absolute latitude value of less than 90 degrees.");
+                    nameof(location1), "The location1 argument must have an absolute latitude value of less than 90.");
             }
 
             if (double.IsInfinity(y2))
             {
                 throw new ArgumentOutOfRangeException(
-                    nameof(location2), "The parameter location2 must have an absolute latitude value of less than 90 degrees.");
+                    nameof(location2), "The location2 argument must have an absolute latitude value of less than 90.");
             }
 
             var lon1 = location1.Longitude;
@@ -154,12 +155,12 @@ namespace MapControl
             var dlon = lon2 - lon1;
             var dy = y2 - y1;
 
-            // sec(beta) = 1 / cos(atan(dx,dy)) = sqrt(1 + (dx/dy)^2)
+            // sec(beta) = 1 / cos(atan(dlon,dy)) = sqrt(1 + (dlon/dy)^2)
             var sec = Math.Sqrt(1d + dlon * dlon / (dy * dy));
 
             var s12 = sec < 1000d
                 ? Math.Abs(dlat * Math.PI / 180d * sec)
-                : Math.Abs(dlon * Math.PI / 180d);
+                : Math.Abs(dlon * Math.PI / 180d * Math.Cos((lat1 + lat2) * Math.PI / 360d));
 
             var locations = new LocationCollection(new Location(lat1, lon1));
 
diff --git a/MapControl/Shared/WmtsTileMatrixSet.cs b/MapControl/Shared/WmtsTileMatrixSet.cs
index 795243b6..9a9fd8fc 100644
--- a/MapControl/Shared/WmtsTileMatrixSet.cs
+++ b/MapControl/Shared/WmtsTileMatrixSet.cs
@@ -18,17 +18,17 @@ namespace MapControl
         {
             if (string.IsNullOrEmpty(identifier))
             {
-                throw new ArgumentException("The parameter identifier must not be null or empty.");
+                throw new ArgumentException("The identifier argument must not be null or empty.", nameof(identifier));
             }
 
             if (string.IsNullOrEmpty(supportedCrs))
             {
-                throw new ArgumentException("The parameter supportedCrs must not be null or empty.");
+                throw new ArgumentException("The supportedCrs argument must not be null or empty.", nameof(supportedCrs));
             }
 
-            if (tileMatrixes == null || tileMatrixes.Count() <= 0)
+            if (tileMatrixes == null || !tileMatrixes.Any())
             {
-                throw new ArgumentException("The parameter tileMatrixes must not be null or an empty collection.");
+                throw new ArgumentException("The tileMatrixes argument must not be null or an empty collection.", nameof(tileMatrixes));
             }
 
             Identifier = identifier;
diff --git a/MapControl/UWP/ImageFileCache.UWP.cs b/MapControl/UWP/ImageFileCache.UWP.cs
index deacb094..5a31d7d6 100644
--- a/MapControl/UWP/ImageFileCache.UWP.cs
+++ b/MapControl/UWP/ImageFileCache.UWP.cs
@@ -17,7 +17,7 @@ namespace MapControl.Caching
 
         public ImageFileCache(StorageFolder folder)
         {
-            this.folder = folder ?? throw new ArgumentNullException("The parameter rootFolder must not be null.");
+            this.folder = folder ?? throw new ArgumentNullException(nameof(folder));
 
             Debug.WriteLine("Created ImageFileCache in " + folder.Path);
         }
diff --git a/MapControl/WPF/ImageFileCache.WPF.cs b/MapControl/WPF/ImageFileCache.WPF.cs
index 56ec8f63..0e483a6a 100644
--- a/MapControl/WPF/ImageFileCache.WPF.cs
+++ b/MapControl/WPF/ImageFileCache.WPF.cs
@@ -34,7 +34,7 @@ namespace MapControl.Caching
         {
             if (string.IsNullOrEmpty(directory))
             {
-                throw new ArgumentException("The parameter directory must not be null or empty.");
+                throw new ArgumentException("The directory argument must not be null or empty.", nameof(directory));
             }
 
             rootDirectory = directory;
@@ -85,7 +85,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             return memoryCache.Contains(key) || FindFile(key) != null;
@@ -100,7 +100,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             var imageCacheItem = memoryCache.Get(key) as ImageCacheItem;
@@ -157,12 +157,12 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             if (!(value is ImageCacheItem imageCacheItem))
             {
-                throw new ArgumentException("The parameter value must be a MapControl.Caching.ImageCacheItem instance.");
+                throw new ArgumentException("The value argument must be a MapControl.Caching.ImageCacheItem instance.", nameof(value));
             }
 
             memoryCache.Set(key, imageCacheItem, policy);
@@ -239,7 +239,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             memoryCache.Remove(key);
diff --git a/MapProjections/Shared/GeoApiProjection.cs b/MapProjections/Shared/GeoApiProjection.cs
index a48295fd..1ae0b627 100644
--- a/MapProjections/Shared/GeoApiProjection.cs
+++ b/MapProjections/Shared/GeoApiProjection.cs
@@ -39,7 +39,7 @@ namespace MapControl.Projections
             get { return coordinateSystem; }
             set
             {
-                coordinateSystem = value ?? throw new ArgumentNullException("The property value must not be null.");
+                coordinateSystem = value ?? throw new ArgumentNullException(nameof(value));
 
                 var transformFactory = new CoordinateTransformationFactory();
 
diff --git a/MapProjections/Shared/UtmProjection.cs b/MapProjections/Shared/UtmProjection.cs
index a7a8db7c..9b00b912 100644
--- a/MapProjections/Shared/UtmProjection.cs
+++ b/MapProjections/Shared/UtmProjection.cs
@@ -40,7 +40,7 @@ namespace MapControl.Projections
         {
             if (zoneNumber < 1 || zoneNumber > 61)
             {
-                throw new ArgumentException("Invalid UTM zone number.");
+                throw new ArgumentException("Invalid UTM zone number.", nameof(zoneNumber));
             }
 
             var zoneName = zoneNumber.ToString() + (north ? "N" : "S");
diff --git a/SQLiteCache/UWP/SQLiteCache.UWP.cs b/SQLiteCache/UWP/SQLiteCache.UWP.cs
index 766a5acd..a79b2ad9 100644
--- a/SQLiteCache/UWP/SQLiteCache.UWP.cs
+++ b/SQLiteCache/UWP/SQLiteCache.UWP.cs
@@ -21,12 +21,12 @@ namespace MapControl.Caching
         {
             if (folder == null)
             {
-                throw new ArgumentNullException("The parameter folder must not be null.");
+                throw new ArgumentNullException(nameof(folder));
             }
 
             if (string.IsNullOrEmpty(fileName))
             {
-                throw new ArgumentException("The parameter fileName must not be null or empty.");
+                throw new ArgumentException("The fileName argument must not be null or empty.", nameof(fileName));
             }
 
             connection = Open(Path.Combine(folder.Path, fileName));
diff --git a/SQLiteCache/WPF/SQLiteCache.WPF.cs b/SQLiteCache/WPF/SQLiteCache.WPF.cs
index 3fda2133..73a1105d 100644
--- a/SQLiteCache/WPF/SQLiteCache.WPF.cs
+++ b/SQLiteCache/WPF/SQLiteCache.WPF.cs
@@ -21,7 +21,7 @@ namespace MapControl.Caching
         {
             if (string.IsNullOrEmpty(path))
             {
-                throw new ArgumentException("The parameter path must not be null or empty.");
+                throw new ArgumentException("The path argument must not be null or empty.", nameof(path));
             }
 
             if (string.IsNullOrEmpty(Path.GetExtension(path)))
@@ -91,7 +91,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             try
@@ -118,7 +118,7 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             try
@@ -166,12 +166,12 @@ namespace MapControl.Caching
 
             if (key == null)
             {
-                throw new ArgumentNullException("The parameter key must not be null.");
+                throw new ArgumentNullException(nameof(key));
             }
 
             if (!(value is ImageCacheItem imageCacheItem))
             {
-                throw new ArgumentException("The parameter value must be a MapControl.Caching.ImageCacheItem instance.");
+                throw new ArgumentException("The value argument must be a MapControl.Caching.ImageCacheItem instance.", nameof(value));
             }
 
             try