diff --git a/rtgui/adjuster.cc b/rtgui/adjuster.cc
index 662fc5bf2..f35cff80e 100644
--- a/rtgui/adjuster.cc
+++ b/rtgui/adjuster.cc
@@ -22,6 +22,7 @@
 #include <multilangmgr.h>
 #include <rtengine.h>
 #include <options.h>
+#include <guiutils.h>
 
 extern Glib::ustring argv0;
 
@@ -258,10 +259,9 @@ Glib::ustring Adjuster::getTextValue () {
 
 bool Adjuster::notifyListener () {
 
-  if (adjusterListener!=NULL  && !blocked) {
-	  gdk_threads_enter();
-	  adjusterListener->adjusterChanged (this, spin->get_value ());
-	  gdk_threads_leave();
+  if (adjusterListener!=NULL && !blocked) {
+    GThreadLock lock;
+    adjusterListener->adjusterChanged (this, spin->get_value ());
   }
   return false;
 }
@@ -271,6 +271,7 @@ void Adjuster::setEnabled (bool enabled) {
     spin->set_sensitive (enabled);
     slider->set_sensitive (enabled);
 }
+
 void Adjuster::setEditedState (EditedState eState) {
 
     if (editedState!=eState) {
diff --git a/rtgui/batchqueue.cc b/rtgui/batchqueue.cc
index 6267ce48a..5d87f06e1 100644
--- a/rtgui/batchqueue.cc
+++ b/rtgui/batchqueue.cc
@@ -209,12 +209,10 @@ Glib::ustring BatchQueue::getTempFilenameForParams( const Glib::ustring filename
     return savedParamPath;
 }
 
-int deleteitem (void* data)
+int cancelItemUI (void* data)
 {
-	safe_g_remove(  ((BatchQueueEntry*)data)->savedParamsFile );
-    gdk_threads_enter ();
+	safe_g_remove( ((BatchQueueEntry*)data)->savedParamsFile );
     delete (BatchQueueEntry*)data;
-    gdk_threads_leave ();
     return 0;
 }
 
@@ -235,7 +233,7 @@ void BatchQueue::cancelItems (std::vector<ThumbBrowserEntryBase*>* items) {
                 rtengine::ProcessingJob::destroy (entry->job);
                 if (entry->thumbnail)
                     entry->thumbnail->imageRemovedFromQueue ();
-                g_idle_add (deleteitem, entry);
+                g_idle_add (cancelItemUI, entry);
             }
         }
         for (int i=0; i<fd.size(); i++) 
@@ -351,8 +349,8 @@ void BatchQueue::startProcessing () {
 }
 
 rtengine::ProcessingJob* BatchQueue::imageReady (rtengine::IImage16* img) {
+    GThreadLock lock;
 
-    gdk_threads_enter ();
     // save image img
     Glib::ustring fname;
     SaveFormat saveFormat;
@@ -443,7 +441,7 @@ rtengine::ProcessingJob* BatchQueue::imageReady (rtengine::IImage16* img) {
 
     redraw ();
     notifyListener ();
-    gdk_threads_leave ();
+
     return processing ? processing->job : NULL;
 }
 
@@ -575,11 +573,8 @@ Glib::ustring BatchQueue::autoCompleteFileName (const Glib::ustring& fileName, c
     }
 }
 
-int bqredraw (void* p) {
-
-    gdk_threads_enter ();
+int setProgressUI (void* p) {
     ((BatchQueue*)p)->redraw();
-    gdk_threads_leave ();
     return 0;
 }
 
@@ -588,7 +583,7 @@ void BatchQueue::setProgress (double p) {
     if (processing)
         processing->progress = p;
 
-    g_idle_add (bqredraw, this);
+    g_idle_add (setProgressUI, this);
 }
 
 void BatchQueue::buttonPressed (LWButton* button, int actionCode, void* actionData) {
@@ -609,13 +604,10 @@ struct NLParams {
     int qsize;
 };
 
-int bqnotifylistener (void* data) {
-
-    gdk_threads_enter ();
+int bqnotifylistenerUI (void* data) {
     NLParams* params = (NLParams*)data;
     params->listener->queueSizeChanged (params->qsize);
     delete params;
-    gdk_threads_leave ();
     return 0;
 }
 
@@ -625,7 +617,7 @@ void BatchQueue::notifyListener () {
         NLParams* params = new NLParams;
         params->listener = listener;
         params->qsize = fd.size();
-        g_idle_add (bqnotifylistener, params);
+        g_idle_add (bqnotifylistenerUI, params);
     }
 }
 
diff --git a/rtgui/batchqueueentry.cc b/rtgui/batchqueueentry.cc
index 1d339ce20..7487c22d6 100644
--- a/rtgui/batchqueueentry.cc
+++ b/rtgui/batchqueueentry.cc
@@ -109,7 +109,6 @@ struct BQUpdateParam {
 
 int updateImageUIThread (void* data) {
 
-    gdk_threads_enter ();
     BQUpdateParam* params = (BQUpdateParam*)data;
 
     BatchQueueEntryIdleHelper* bqih = params->bqih;
@@ -122,14 +121,13 @@ int updateImageUIThread (void* data) {
             bqih->pending--;
         delete [] params->img;
         delete params;
-        gdk_threads_leave ();
+
         return 0;
     }
     
     bqih->bqentry->_updateImage (params->img, params->w, params->h);
     bqih->pending--;
     
-    gdk_threads_leave ();
     delete params;
     return 0;
 }
diff --git a/rtgui/crop.cc b/rtgui/crop.cc
index b3a2d0af3..f72f64ecd 100644
--- a/rtgui/crop.cc
+++ b/rtgui/crop.cc
@@ -436,34 +436,28 @@ void Crop::enabledChanged () {
     }
 }
 
-int notifylistener (void* data) {
-
-    gdk_threads_enter ();
+int notifyListenerUI (void* data) {
     ((Crop*)data)->notifyListener ();
-    gdk_threads_leave ();
     return 0;
 }
 
-int refreshspins (void* data) {
-
-    gdk_threads_enter ();
+int refreshSpinsUI (void* data) {
     RefreshSpinHelper* rsh = (RefreshSpinHelper*) data;
     rsh->crop->refreshSpins (rsh->notify);
     delete rsh;
-    gdk_threads_leave ();
     return 0;
 }
 
 void Crop::hFlipCrop () {
 
     nx = maxw - nx - nw;
-    g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+    g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 }
 
 void Crop::vFlipCrop () {
 
     ny = maxh - ny - nh;
-    g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+    g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 }
 
 void Crop::rotateCrop (int deg) {
@@ -493,7 +487,7 @@ void Crop::rotateCrop (int deg) {
     }
 
     lastRotationDeg = deg;
-    g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+    g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 }
 
 void Crop::positionChanged () {
@@ -506,7 +500,7 @@ void Crop::positionChanged () {
     int W = nw;
     int H = nh;
     cropMoved (X, Y, W, H);
-    g_idle_add (notifylistener, this);
+    g_idle_add (notifyListenerUI, this);
 }
 
 void Crop::widthChanged () {
@@ -518,7 +512,7 @@ void Crop::widthChanged () {
     int W = (int)w->get_value ();
     int H = nh;
     cropWidth2Resized (X, Y, W, H);
-    g_idle_add (notifylistener, this);
+    g_idle_add (notifyListenerUI, this);
 }
 
 void Crop::heightChanged () {
@@ -530,7 +524,7 @@ void Crop::heightChanged () {
     int W = nw;
     int H = (int)h->get_value ();
     cropHeight2Resized (X, Y, W, H);
-    g_idle_add (notifylistener, this);
+    g_idle_add (notifyListenerUI, this);
 }
 
 
@@ -563,7 +557,7 @@ void Crop::ratioChanged () {
     else 
       cropHeight2Resized (X, Y, W, H);
 
-    g_idle_add (refreshspins, new RefreshSpinHelper (this, true));
+    g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, true));
   }
 }
 
@@ -628,13 +622,10 @@ struct setdimparams {
     int y;
 };
 
-int setdim (void* data) {
-
-    gdk_threads_enter ();
+int sizeChangedUI (void* data) {
     setdimparams* params = (setdimparams*)data;
     params->crop->setDimensions (params->x, params->y);
     delete params;
-    gdk_threads_leave ();
     return 0;
 }
 
@@ -644,7 +635,7 @@ void Crop::sizeChanged (int x, int y, int ow, int oh) {
     params->x = x;
     params->y = y;
     params->crop = this;
-    g_idle_add (setdim, params);
+    g_idle_add (sizeChangedUI, params);
 }
 
 bool Crop::refreshSpins (bool notify) {
@@ -697,7 +688,7 @@ void Crop::cropMoved (int &X, int &Y, int &W, int &H) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -727,7 +718,7 @@ void Crop::cropWidth1Resized (int &X, int &Y, int &W, int &H) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -759,7 +750,7 @@ void Crop::cropWidth2Resized (int &X, int &Y, int &W, int &H) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -790,7 +781,7 @@ void Crop::cropHeight1Resized (int &X, int &Y, int &W, int &H) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -821,7 +812,7 @@ void Crop::cropHeight2Resized (int &X, int &Y, int &W, int &H) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -837,7 +828,7 @@ void Crop::cropInit (int &x, int &y, int &w, int &h) {
   econn.block (true);
   enabled->set_active (1);
   econn.block (false);
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
@@ -922,13 +913,13 @@ void Crop::cropResized (int &x, int &y, int& x2, int& y2) {
   nw = W;
   nh = H;
 
-  g_idle_add (refreshspins, new RefreshSpinHelper (this, false));
+  g_idle_add (refreshSpinsUI, new RefreshSpinHelper (this, false));
 //  Glib::signal_idle().connect (sigc::mem_fun(*this, &Crop::refreshSpins));
 }
 
 void Crop::cropManipReady () {
 
-    g_idle_add (notifylistener, this);
+    g_idle_add (notifyListenerUI, this);
 }
 
 double Crop::getRatio () {
diff --git a/rtgui/crophandler.cc b/rtgui/crophandler.cc
index 51f998763..f1c28be21 100644
--- a/rtgui/crophandler.cc
+++ b/rtgui/crophandler.cc
@@ -20,6 +20,7 @@
 #undef THREAD_PRIORITY_NORMAL
 
 #include <cstring>
+#include <guiutils.h>
 
 using namespace rtengine;
 
@@ -157,7 +158,7 @@ void CropHandler::getPosition (int& x, int& y) {
 
 int createpixbufs (void* data) {
 
-    gdk_threads_enter ();
+    GThreadLock lock;
 
     CropHandlerIdleHelper* chi = (CropHandlerIdleHelper*) data;
     if (chi->destroyed) {
@@ -165,7 +166,7 @@ int createpixbufs (void* data) {
             delete chi;
         else    
             chi->pending--;
-        gdk_threads_leave ();
+
         return 0;
     }
    
@@ -180,7 +181,6 @@ int createpixbufs (void* data) {
 		delete [] ch->cropimgtrue;
         ch->cropimgtrue = NULL;
         ch->cimg.unlock ();
-        gdk_threads_leave ();
         return 0;
     }    
 
@@ -221,7 +221,6 @@ int createpixbufs (void* data) {
   
     chi->pending--;
     
-    gdk_threads_leave ();
     return 0;
 }
 
diff --git a/rtgui/dirbrowser.cc b/rtgui/dirbrowser.cc
index 4edb465d1..e95344c36 100644
--- a/rtgui/dirbrowser.cc
+++ b/rtgui/dirbrowser.cc
@@ -25,6 +25,7 @@
 #include <safegtk.h>
 
 #include <cstring>
+#include <guiutils.h>
 
 #define CHECKTIME 5000
 extern Glib::ustring argv0;
@@ -142,7 +143,7 @@ void DirBrowser::updateVolumes () {
 
     int nvolumes = GetLogicalDrives ();
     if (nvolumes!=volumes) {
-		gdk_threads_enter();
+		GThreadLock lock;
 
         for (int i=0; i<32; i++) 
             if (((volumes >> i) & 1) && !((nvolumes >> i) & 1)) { // volume i has been deleted
@@ -155,27 +156,21 @@ void DirBrowser::updateVolumes () {
             else if (!((volumes >> i) & 1) && ((nvolumes >> i) & 1)) 
                 addRoot ('A'+i); // volume i has been added
         volumes = nvolumes;
-
-		gdk_threads_leave();
     }
 }
 
-int _updateVolumes (void* br) {
-
+int updateVolumesUI (void* br) {
     ((DirBrowser*)br)->updateVolumes ();
     return 1;
 }
-int _updateDirTree (void* br) {
-
-    gdk_threads_enter ();
+int updateDirTreeUI (void* br) {
     ((DirBrowser*)br)->updateDirTreeRoot ();
-    gdk_threads_leave ();
     return 0;
 }
 
 void DirBrowser::winDirChanged () {
 
-    g_idle_add (_updateDirTree, this);
+    g_idle_add (updateDirTreeUI, this);
 }
 #endif
 
@@ -187,7 +182,7 @@ void DirBrowser::fillRoot () {
     if ((volumes >> i) & 1) 
         addRoot ('A'+i);
   // since sigc++ is not thread safe, we have to use the glib function
-  g_timeout_add (CHECKTIME, _updateVolumes, this);
+  g_timeout_add (CHECKTIME, updateVolumesUI, this);
 #else
   Gtk::TreeModel::Row rootRow = *(dirTreeModel->append());
   rootRow[dtColumns.filename] = "/";
diff --git a/rtgui/editorpanel.cc b/rtgui/editorpanel.cc
index 7862db91a..c1b5eafbf 100644
--- a/rtgui/editorpanel.cc
+++ b/rtgui/editorpanel.cc
@@ -502,7 +502,6 @@ struct spsparams {
 
 int setProgressStateUIThread (void* data) {
 
-    gdk_threads_enter ();
     spsparams* p = (spsparams*)data;
 
     if (p->epih->destroyed) {
@@ -511,14 +510,14 @@ int setProgressStateUIThread (void* data) {
         else
             p->epih->pending--;
         delete p;
-        gdk_threads_leave ();
+
         return 0;
     }
 
     p->epih->epanel->refreshProcessingState (p->inProcessing);
     p->epih->pending--;
     delete p;
-    gdk_threads_leave ();
+
     return 0;
 }
 
@@ -637,9 +636,7 @@ void EditorPanel::displayError (Glib::ustring descr) {
     }
 }
 
-int disperror (void* data) {
-
-    gdk_threads_enter ();
+int disperrorUI (void* data) {
     errparams* p = (errparams*)data;
 
     if (p->epih->destroyed) {
@@ -648,14 +645,14 @@ int disperror (void* data) {
         else
             p->epih->pending--;
         delete p;
-        gdk_threads_leave ();
+
         return 0;
     }
 
     p->epih->epanel->displayError (p->descr);
     p->epih->pending--;
     delete p;
-    gdk_threads_leave ();
+
     return 0;
 }
 
@@ -665,7 +662,7 @@ void EditorPanel::error (Glib::ustring descr) {
     errparams* p = new errparams;
     p->descr = descr;
     p->epih = epih;
-    g_idle_add (disperror, p);
+    g_idle_add (disperrorUI, p);
 }
 
 void EditorPanel::info_toggled () {
diff --git a/rtgui/filebrowser.cc b/rtgui/filebrowser.cc
index e9cd5806a..21de79db5 100644
--- a/rtgui/filebrowser.cc
+++ b/rtgui/filebrowser.cc
@@ -313,8 +313,6 @@ int AddEntryUIThread (void* data) {
     addparams* ap = (addparams*) data;
     FileBrowserIdleHelper* fbih = ap->fbih;
 
-    gdk_threads_enter();
-
     if (fbih->destroyed) {
         if (fbih->pending == 1)
             delete fbih;
@@ -322,14 +320,14 @@ int AddEntryUIThread (void* data) {
             fbih->pending--;
         delete ap->entry;
         delete ap;
-        gdk_threads_leave ();
+
         return 0;
     }
 
     ap->fbih->fbrowser->addEntry_ (ap->entry);
     delete ap;
     fbih->pending--;
-    gdk_threads_leave();
+
     return 0;
 }
 
diff --git a/rtgui/filebrowserentry.cc b/rtgui/filebrowserentry.cc
index 8ff6a2801..dd0c8841d 100644
--- a/rtgui/filebrowserentry.cc
+++ b/rtgui/filebrowserentry.cc
@@ -158,13 +158,11 @@ struct tiupdate {
     rtengine::procparams::CropParams cropParams;
 };
 
-int fbeupdate (void* data) {
+int updateImageUI (void* data) {
     
     tiupdate* params = (tiupdate*)data;
     FileBrowserEntryIdleHelper* feih = params->feih;
 
-	GThreadLock lock;
-
     if (feih->destroyed) {
         if (feih->pending == 1)
             delete feih;
@@ -204,7 +202,7 @@ void FileBrowserEntry::updateImage (rtengine::IImage8* img, double scale, rtengi
     param->img = img;
     param->scale = scale;
     param->cropParams = cropParams;
-    g_idle_add (fbeupdate, param);
+    g_idle_add (updateImageUI, param);
 }
 
 void FileBrowserEntry::_updateImage (rtengine::IImage8* img, double s, rtengine::procparams::CropParams cropParams) {
diff --git a/rtgui/filecatalog.cc b/rtgui/filecatalog.cc
index d54d9f5b9..83e5335a5 100644
--- a/rtgui/filecatalog.cc
+++ b/rtgui/filecatalog.cc
@@ -550,19 +550,18 @@ void FileCatalog::_refreshProgressBar () {
     }
 }
 
-int refreshpb (void* data) {
-
-    gdk_threads_enter ();
+int refreshProgressBarUI (void* data) {
     ((FileCatalog*)data)->_refreshProgressBar ();
-    gdk_threads_leave ();
     return 0;
 }
 
 void FileCatalog::previewReady (int dir_id, FileBrowserEntry* fdn) {
     GThreadLock lock;
-	_previewReady (dir_id,fdn);
+    previewReadyUI (dir_id,fdn);
 }
-void FileCatalog::_previewReady (int dir_id, FileBrowserEntry* fdn) {
+
+// Called WITHIN gtk thread
+void FileCatalog::previewReadyUI (int dir_id, FileBrowserEntry* fdn) {
 
 	if ( dir_id != selectedDirectoryId )
 	{
@@ -597,18 +596,18 @@ void FileCatalog::_previewReady (int dir_id, FileBrowserEntry* fdn) {
     dirEFS.cameras.insert (cfs->camera);
     dirEFS.lenses.insert (cfs->lens);
     previewsLoaded++;
-    g_idle_add (refreshpb, this);
+
+    g_idle_add (refreshProgressBarUI, this);
 }
 
 int prevfinished (void* data) {
-
-    gdk_threads_enter();
-    ((FileCatalog*)data)->_previewsFinished ();
-    gdk_threads_leave();
+ 	GThreadLock lock;
+    ((FileCatalog*)data)->previewsFinishedUI ();
     return 0;
 }
 
-void FileCatalog::_previewsFinished () {
+// Called within GTK UI thread
+void FileCatalog::previewsFinishedUI () {
 
     redrawAll ();
     previewsToLoad = 0;
@@ -631,8 +630,6 @@ void FileCatalog::_previewsFinished () {
 
 void FileCatalog::previewsFinished (int dir_id) {
 
- 	GThreadLock lock;
-
 	if ( dir_id != selectedDirectoryId )
 	{
 		return;
@@ -684,13 +681,11 @@ struct FCOIParams {
     std::vector<Thumbnail*> tmb;
 };
 
-int fcopenimg (void* p) {
-
-    gdk_threads_enter ();
+int openRequestedUI (void* p) {
     FCOIParams* params = (FCOIParams*)p;
     params->catalog->_openImage (params->tmb);
     delete params;
-    gdk_threads_leave ();
+
     return 0;
 }
 
@@ -701,7 +696,7 @@ void FileCatalog::openRequested  (std::vector<Thumbnail*> tmb) {
     params->tmb = tmb;
     for (size_t i=0; i<tmb.size(); i++)
         tmb[i]->increaseRef ();
-    g_idle_add (fcopenimg, params);
+    g_idle_add (openRequestedUI, params);
 }
 
 void FileCatalog::deleteRequested  (std::vector<FileBrowserEntry*> tbe, bool inclBatchProcessed) {
@@ -1275,10 +1270,7 @@ void FileCatalog::reparseDirectory () {
 
 #ifdef WIN32
 int winDirChangedUITread (void* cat) {
-	gdk_threads_enter ();
     ((FileCatalog*)cat)->reparseDirectory ();
-    gdk_threads_leave ();
-
     return 0;
 }
 
@@ -1331,13 +1323,13 @@ void FileCatalog::addAndOpenFile (const Glib::ustring& fname) {
         Thumbnail* tmb = cacheMgr->getEntry (file->get_parse_name());
         if (tmb) {
             FileBrowserEntry* entry = new FileBrowserEntry (tmb, file->get_parse_name());
-			_previewReady (selectedDirectoryId,entry);
+			previewReadyUI (selectedDirectoryId,entry);
             // open the file
             FCOIParams* params = new FCOIParams;
             params->catalog = this;
             params->tmb.push_back (tmb);
             tmb->increaseRef ();
-            g_idle_add (fcopenimg, params);
+            g_idle_add (openRequestedUI, params);
         }
     }
 }
diff --git a/rtgui/filecatalog.h b/rtgui/filecatalog.h
index ccaff58e6..c317cad9b 100644
--- a/rtgui/filecatalog.h
+++ b/rtgui/filecatalog.h
@@ -163,10 +163,10 @@ class FileCatalog : public Gtk::VBox,
                 void refreshEditedState (const std::set<Glib::ustring>& efiles);
                 
                 // previewloaderlistener interface
-				void _previewReady (int dir_id, FileBrowserEntry* fdn);
+				void previewReadyUI (int dir_id, FileBrowserEntry* fdn);
 				void previewReady (int dir_id, FileBrowserEntry* fdn);
 				void previewsFinished (int dir_id);
-                void _previewsFinished ();
+                void previewsFinishedUI ();
                 void _refreshProgressBar ();
 
 				// filterpanel interface
diff --git a/rtgui/filepanel.cc b/rtgui/filepanel.cc
index 05eb75588..b34279f27 100644
--- a/rtgui/filepanel.cc
+++ b/rtgui/filepanel.cc
@@ -21,12 +21,8 @@
 #include <rtwindow.h>
 #include <safegtk.h>
 
-int fbinit (void* data) {
-
-    gdk_threads_enter ();
+int FilePanelInitUI (void* data) {
     ((FilePanel*)data)->init ();
-    gdk_threads_leave ();
-
     return 0;
 }
 
@@ -112,7 +108,7 @@ FilePanel::FilePanel () : parent(NULL) {
     fileCatalog->setFileSelectionChangeListener (tpc);
 
     fileCatalog->setFileSelectionListener (this);
-    g_idle_add (fbinit, this);
+    g_idle_add (FilePanelInitUI, this);
 
     show_all ();
 }
diff --git a/rtgui/histogrampanel.cc b/rtgui/histogrampanel.cc
index a1fddcafd..d6bbce52b 100644
--- a/rtgui/histogrampanel.cc
+++ b/rtgui/histogrampanel.cc
@@ -112,9 +112,7 @@ void HistogramArea::updateOptions (bool r, bool g, bool b, bool l, bool raw) {
     renderHistogram ();
 }
 
-int histupdate (void* data) {
-
-    gdk_threads_enter ();
+int histupdateUI (void* data) {
 
     HistogramAreaIdleHelper* haih = (HistogramAreaIdleHelper*)data;
 
@@ -123,7 +121,7 @@ int histupdate (void* data) {
             delete haih;
         else    
             haih->pending--;
-        gdk_threads_leave ();
+
         return 0;
     }
     
@@ -131,7 +129,7 @@ int histupdate (void* data) {
     haih->harea->queue_draw ();
 
     haih->pending--;
-    gdk_threads_leave ();
+
     return 0;
 }
 
@@ -148,7 +146,7 @@ void HistogramArea::update (LUTu &histRed, LUTu &histGreen, LUTu &histBlue, LUTu
         valid = false;
 	
     haih->pending++;
-    g_idle_add (histupdate, haih);
+    g_idle_add (histupdateUI, haih);
 }
 
 void HistogramArea::renderHistogram () {
diff --git a/rtgui/mydiagonalcurve.cc b/rtgui/mydiagonalcurve.cc
index 6d21b4436..6face4c8d 100644
--- a/rtgui/mydiagonalcurve.cc
+++ b/rtgui/mydiagonalcurve.cc
@@ -701,9 +701,7 @@ void MyDiagonalCurve::setActiveParam (int ac) {
     queue_draw ();
 }
 
-int diagonalmchistupdate (void* data) {
-
-    gdk_threads_enter ();
+int diagonalmchistupdateUI (void* data) {
 
     MyCurveIdleHelper* mcih = (MyCurveIdleHelper*)data;
 
@@ -712,7 +710,7 @@ int diagonalmchistupdate (void* data) {
             delete mcih;
         else    
             mcih->pending--;
-        gdk_threads_leave ();
+
         return 0;
     }
 
@@ -720,7 +718,7 @@ int diagonalmchistupdate (void* data) {
     mcih->myCurve->queue_draw ();
 
     mcih->pending--;
-    gdk_threads_leave ();
+
     return 0;
 }
 
@@ -736,7 +734,7 @@ void MyDiagonalCurve::updateBackgroundHistogram (LUTu & hist) {
         bghistvalid = false;
 
     mcih->pending++;
-    g_idle_add (diagonalmchistupdate, mcih);
+    g_idle_add (diagonalmchistupdateUI, mcih);
 
 }
 
diff --git a/rtgui/myflatcurve.cc b/rtgui/myflatcurve.cc
index a0af94bc6..d2cd21547 100644
--- a/rtgui/myflatcurve.cc
+++ b/rtgui/myflatcurve.cc
@@ -1279,43 +1279,6 @@ void MyFlatCurve::setType (FlatCurveType t) {
     pixmap.clear ();
 }
 
-/*int flatmchistupdate (void* data) {
-
-    gdk_threads_enter ();
-
-    MyFlatCurveIdleHelper* mcih = (MyFlatCurveIdleHelper*)data;
-
-    if (mcih->destroyed) {
-        if (mcih->pending == 1)
-            delete mcih;
-        else    
-            mcih->pending--;
-        gdk_threads_leave ();
-        return 0;
-    }
-    
-    mcih->clearPixmap ();
-    mcih->myCurve->queue_draw ();
-
-    mcih->pending--;
-    gdk_threads_leave ();
-    return 0;
-}*/
-
-/*void MyFlatCurve::updateBackgroundHistogram (unsigned int* hist) {
-
-    if (hist!=NULL) {
-        memcpy (bghist, hist, 256*sizeof(unsigned int));
-        bghistvalid = true;
-    }
-    else
-        bghistvalid = false;
-
-    mcih->pending++;
-    g_idle_add (flatmchistupdate, mcih);
-
-}*/
-
 void MyFlatCurve::reset() {
 	innerWidth = get_allocation().get_width() - RADIUS * 2;
 	innerHeight = get_allocation().get_height() - RADIUS * 2;
diff --git a/rtgui/placesbrowser.cc b/rtgui/placesbrowser.cc
index 58c8a48f5..45332a734 100644
--- a/rtgui/placesbrowser.cc
+++ b/rtgui/placesbrowser.cc
@@ -20,6 +20,7 @@
 #include <options.h>
 #include <toolpanel.h>
 #include <safegtk.h>
+#include <guiutils.h>
 
 PlacesBrowser::PlacesBrowser () : listener (NULL) {
 
@@ -211,24 +212,18 @@ bool PlacesBrowser::rowSeparatorFunc (const Glib::RefPtr<Gtk::TreeModel>& model,
 }
 
 void PlacesBrowser::mountChanged (const Glib::RefPtr<Gio::Mount>& m) {
-
-    gdk_threads_enter ();
+    GThreadLock lock;
     refreshPlacesList ();
-    gdk_threads_leave ();
 }
 
 void PlacesBrowser::volumeChanged (const Glib::RefPtr<Gio::Volume>& m) {
-
-    gdk_threads_enter ();
+    GThreadLock lock;
     refreshPlacesList ();
-    gdk_threads_leave ();
 }
 
 void PlacesBrowser::driveChanged (const Glib::RefPtr<Gio::Drive>& m) {
-
-    gdk_threads_enter ();
+    GThreadLock lock;
     refreshPlacesList ();
-    gdk_threads_leave ();
 }
 
 void PlacesBrowser::selectionChanged () {
diff --git a/rtgui/previewhandler.cc b/rtgui/previewhandler.cc
index 3ce660c14..deec8e2f4 100644
--- a/rtgui/previewhandler.cc
+++ b/rtgui/previewhandler.cc
@@ -48,10 +48,7 @@ struct iaimgpar {
     CropParams cp;
 };
 
-int setImageThread (void* data) {
-
-    gdk_threads_enter ();
-
+int setImageUI (void* data) {
     iaimgpar* iap = (iaimgpar*)data;
     PreviewHandlerIdleHelper* pih = iap->pih;
 
@@ -61,7 +58,7 @@ int setImageThread (void* data) {
         else    
             pih->pending--;
         delete iap;
-        gdk_threads_leave ();
+
         return 0;
     }
 
@@ -78,8 +75,6 @@ int setImageThread (void* data) {
     pih->phandler->previewScale = iap->scale;
     pih->pending--;
     delete iap;
-
-    gdk_threads_leave ();
     
     return 0;
 }
@@ -94,13 +89,11 @@ void PreviewHandler::setImage (rtengine::IImage8* i, double scale, rtengine::pro
     iap->scale      = scale;
     iap->cp         = cp;
 
-    g_idle_add (setImageThread, iap);
+    g_idle_add (setImageUI, iap);
 }
 
 
-int delImageThread (void* data) {
-
-    gdk_threads_enter ();
+int delImageUI (void* data) {
 
     iaimgpar* iap = (iaimgpar*)data;
     PreviewHandlerIdleHelper* pih = iap->pih;
@@ -111,7 +104,7 @@ int delImageThread (void* data) {
         else    
             pih->pending--;
         delete iap;
-        gdk_threads_leave ();
+
         return 0;
     }
     
@@ -129,8 +122,6 @@ int delImageThread (void* data) {
     pih->pending--;
     delete iap;
 
-    gdk_threads_leave ();
-
     return 0;
 }
 
@@ -142,12 +133,10 @@ void PreviewHandler::delImage (IImage8* i) {
     iap->image    = i;
     iap->pih = pih;
 
-    g_idle_add (delImageThread, iap);
+    g_idle_add (delImageUI, iap);
 }
 
-int imageReadyThread (void* data) {
-
-    gdk_threads_enter ();
+int imageReadyUI (void* data) {
     
     iaimgpar* iap = (iaimgpar*)data;
     PreviewHandlerIdleHelper* pih = iap->pih;
@@ -158,7 +147,7 @@ int imageReadyThread (void* data) {
         else    
             pih->pending--;
         delete iap;
-        gdk_threads_leave ();
+
         return 0;
     }
 
@@ -170,8 +159,6 @@ int imageReadyThread (void* data) {
     pih->pending--;
     delete iap;
 
-    gdk_threads_leave ();
-
     return 0;
 }
 
@@ -181,7 +168,7 @@ void PreviewHandler::imageReady (CropParams cp) {
     iaimgpar* iap = new iaimgpar;
     iap->pih      = pih;
     iap->cp       = cp;
-	g_idle_add (imageReadyThread, iap);
+	g_idle_add (imageReadyUI, iap);
 }
 
 Glib::RefPtr<Gdk::Pixbuf> PreviewHandler::getRoughImage (int x, int y, int w, int h, double zoom) {
diff --git a/rtgui/previewhandler.h b/rtgui/previewhandler.h
index f7ced616e..314c240dc 100644
--- a/rtgui/previewhandler.h
+++ b/rtgui/previewhandler.h
@@ -38,9 +38,9 @@ struct PreviewHandlerIdleHelper {
 
 class PreviewHandler : public rtengine::PreviewImageListener {
 
-    friend int setImageThread   (void* data);
-    friend int delImageThread   (void* data);
-    friend int imageReadyThread (void* data);
+    friend int setImageUI   (void* data);
+    friend int delImageUI   (void* data);
+    friend int imageReadyUI (void* data);
 
     protected:
         rtengine::IImage8* image;       
diff --git a/rtgui/progressconnector.h b/rtgui/progressconnector.h
index 4d2facdf2..54539a4a4 100644
--- a/rtgui/progressconnector.h
+++ b/rtgui/progressconnector.h
@@ -22,6 +22,7 @@
 #include <sigc++/sigc++.h>
 #include <gtkmm.h>
 #include <rtengine.h>
+#include <guiutils.h>
 
 #undef THREAD_PRIORITY_NORMAL
 
@@ -35,28 +36,24 @@ class PLDBridge : public rtengine::ProgressListener {
 
     // ProgressListener interface
     void setProgress (double p) {
-        gdk_threads_enter ();
+        GThreadLock lock;
         pl->setProgress(p);
-        gdk_threads_leave ();
     }
     void setProgressStr (Glib::ustring str) {
-        gdk_threads_enter ();
+        GThreadLock lock;
         Glib::ustring progrstr;
         progrstr = M(str);
         pl->setProgressStr(progrstr);
-        gdk_threads_leave ();
     }
 
     void setProgressState (bool inProcessing){
-        gdk_threads_enter ();
+        GThreadLock lock;
         pl->setProgressState(inProcessing);
-        gdk_threads_leave ();
     }
 
     void error (Glib::ustring descr){
-        gdk_threads_enter ();
+        GThreadLock lock;
         pl->error(descr);
-        gdk_threads_leave ();
     }
 };
 
@@ -68,18 +65,18 @@ class ProgressConnector {
         T retval;
         Glib::Thread *workThread;
 
-		static int emitEndSignal (void* data) {
-			gdk_threads_enter ();
+		static int emitEndSignalUI (void* data) {
+
 			sigc::signal0<bool>* opEnd = (sigc::signal0<bool>*) data;
 			int r = opEnd->emit ();
 			delete opEnd;
-			gdk_threads_leave ();
+
 			return r;
 		}
         
         void workingThread () {
             retval = opStart.emit ();
-            g_idle_add (ProgressConnector<T>::emitEndSignal, new sigc::signal0<bool> (opEnd));
+            g_idle_add (ProgressConnector<T>::emitEndSignalUI, new sigc::signal0<bool> (opEnd));
             workThread = 0;
         }
         
diff --git a/rtgui/tonecurve.cc b/rtgui/tonecurve.cc
index b262bdd61..f437de034 100644
--- a/rtgui/tonecurve.cc
+++ b/rtgui/tonecurve.cc
@@ -305,11 +305,8 @@ void ToneCurve::waitForAutoExp () {
     curveEditorG->set_sensitive (false);
 }
 
-int aexpcomputed (void* data) {
-
-    gdk_threads_enter();
+int autoExpChangedUI (void* data) {
     ((ToneCurve*)data)->autoExpComputed_ ();
-    gdk_threads_leave();
     return 0;
 }
 
@@ -317,7 +314,7 @@ void ToneCurve::autoExpChanged (double expcomp, int black) {
 
     nextBlack = black;
     nextExpcomp = expcomp;
-    g_idle_add (aexpcomputed, this);
+    g_idle_add (autoExpChangedUI, this);
 
 //    Glib::signal_idle().connect (sigc::mem_fun(*this, &ToneCurve::autoExpComputed_));
 }