diff --git a/data/en.mse-locale/locale b/data/en.mse-locale/locale
index d3d8b077..a6f895f3 100644
--- a/data/en.mse-locale/locale
+++ b/data/en.mse-locale/locale
@@ -619,7 +619,8 @@ button:
 	check now:			Check &Now
 	always:							Always
 	if internet connection exists:	If internet connection exists
-	never:							Never
+	never:							Never
+	internal image extension: Store images internally with extension
 	
 	# Column select
 	move up:			Move &Up
diff --git a/src/data/settings.cpp b/src/data/settings.cpp
index 6e77441b..12aeebae 100644
--- a/src/data/settings.cpp
+++ b/src/data/settings.cpp
@@ -172,7 +172,8 @@ Settings::Settings()
   , symbol_grid          (true)
   , symbol_grid_snap     (false)
   , print_layout         (LAYOUT_NO_SPACE)
-  , internal_scale       (1.0)
+  , internal_scale       (1.0)
+  , internal_image_extension(true)
   #if USE_OLD_STYLE_UPDATE_CHECKER
   , updates_url          (_("http://magicseteditor.sourceforge.net/updates"))
   #endif
@@ -259,7 +260,8 @@ IMPLEMENT_REFLECTION_NO_SCRIPT(Settings) {
   REFLECT(default_game);
   REFLECT(print_layout);
   REFLECT(apprentice_location);
-  REFLECT(internal_scale);
+  REFLECT(internal_scale);
+  REFLECT(internal_image_extension);
   #if USE_OLD_STYLE_UPDATE_CHECKER
     REFLECT(updates_url);
   #else
diff --git a/src/data/settings.hpp b/src/data/settings.hpp
index 2ced6e4b..7d022df0 100644
--- a/src/data/settings.hpp
+++ b/src/data/settings.hpp
@@ -195,6 +195,7 @@ public:
   
   // --------------------------------------------------- : Internal settings
   double internal_scale;
+  bool internal_image_extension;
 
   // --------------------------------------------------- : Update checking
   #if USE_OLD_STYLE_UPDATE_CHECKER
diff --git a/src/gui/preferences_window.cpp b/src/gui/preferences_window.cpp
index 3ede27bb..e50d6681 100644
--- a/src/gui/preferences_window.cpp
+++ b/src/gui/preferences_window.cpp
@@ -75,6 +75,8 @@ public:
 private:
   DECLARE_EVENT_TABLE();
 
+  wxCheckBox* internal_image_extension;
+
   wxComboBox* internal_scale;
   int internal_scale_int;
 
@@ -313,8 +315,11 @@ END_EVENT_TABLE  ()
 // ----------------------------------------------------------------------------- : Preferences page : internal
 
 InternalPreferencesPage::InternalPreferencesPage(Window* parent) : PreferencesPage(parent) {
+  internal_image_extension = new wxCheckBox(this, wxID_ANY, _BUTTON_("internal image extension"));
   internal_scale = new wxComboBox(this, ID_INTERNAL_SCALE);
 
+  internal_image_extension->SetValue(settings.internal_image_extension);
+
   internal_scale_int = static_cast<int>(settings.internal_scale * 100);
   internal_scale->SetValue(String::Format(_("%d%%"), internal_scale_int));
 
@@ -325,19 +330,22 @@ InternalPreferencesPage::InternalPreferencesPage(Window* parent) : PreferencesPa
 
   wxSizer* s = new wxBoxSizer(wxVERTICAL);
   wxSizer* s2 = new wxStaticBoxSizer(wxVERTICAL, this, _LABEL_("storage"));
-  wxSizer* s3 = new wxBoxSizer(wxHORIZONTAL);
-  s3->Add(new wxStaticText(this, wxID_ANY, _LABEL_("scale")), 0, wxALL & ~wxLEFT, 4);
-  s3->AddSpacer(2);
-  s3->Add(internal_scale);
-  s3->Add(new wxStaticText(this, wxID_ANY, _LABEL_("percent of normal")), 1, wxALL & ~wxRIGHT, 4);
-  s2->Add(s3);
-  s2->Add(new wxStaticText(this, wxID_ANY, _LABEL_("internal scale desc")), 0, wxALL & ~wxLEFT, 4);
+    wxSizer* s3 = new wxBoxSizer(wxHORIZONTAL);
+      s3->Add(new wxStaticText(this, wxID_ANY, _LABEL_("scale")), 0, wxALL & ~wxLEFT, 4);
+      s3->AddSpacer(2);
+      s3->Add(internal_scale);
+      s3->Add(new wxStaticText(this, wxID_ANY, _LABEL_("percent of normal")), 1, wxALL & ~wxRIGHT, 4);
+    s2->Add(s3);
+    s2->Add(new wxStaticText(this, wxID_ANY, _LABEL_("internal scale desc")), 0, wxALL & ~wxLEFT, 4);
+    s2->Add(internal_image_extension, 0, wxEXPAND | wxALL, 4);
   s->Add(s2, 0, wxEXPAND | wxALL, 8);
   s->SetSizeHints(this);
   SetSizer(s);
 }
 
 void InternalPreferencesPage::store() {
+  settings.internal_image_extension = internal_image_extension->GetValue();
+
   updateInternalScale();
   settings.internal_scale = internal_scale_int / 100.0;
 }
@@ -356,7 +364,7 @@ void InternalPreferencesPage::updateInternalScale() {
 }
 
 BEGIN_EVENT_TABLE(InternalPreferencesPage, wxPanel)
-EVT_COMBOBOX(ID_INTERNAL_SCALE, InternalPreferencesPage::onInternalScaleChange)
+  EVT_COMBOBOX(ID_INTERNAL_SCALE, InternalPreferencesPage::onInternalScaleChange)
 END_EVENT_TABLE()
 
 // ----------------------------------------------------------------------------- : Preferences page : directories
diff --git a/src/gui/value/image.cpp b/src/gui/value/image.cpp
index 21399a05..2ba17163 100644
--- a/src/gui/value/image.cpp
+++ b/src/gui/value/image.cpp
@@ -49,7 +49,7 @@ void ImageValueEditor::sliceImage(const Image& image) {
   // clicked ok?
   if (s.ShowModal() == wxID_OK) {
     // store the image into the set
-    LocalFileName new_image_file = getLocalPackage().newFileName(field().name,_(".png")); // a new unique name in the package
+    LocalFileName new_image_file = getLocalPackage().newFileName(field().name, settings.internal_image_extension ? _(".png") : _("")); // a new unique name in the package
     Image img = s.getImage();
     img.SaveFile(getLocalPackage().nameOut(new_image_file), wxBITMAP_TYPE_PNG); // always use PNG images, see #69. Disk space is cheap anyway.
     addAction(value_action(valueP(), new_image_file));