diff --git a/rtdata/languages/default b/rtdata/languages/default
index 2968d3ef2..052d07c50 100644
--- a/rtdata/languages/default
+++ b/rtdata/languages/default
@@ -762,7 +762,7 @@ HISTORY_MSG_506;L*a*b Spot locYT
 HISTORY_MSG_507;L*a*b Spot center
 HISTORY_MSG_508;L*a*b Spot circrad
 HISTORY_MSG_509;L*a*b Spot quality method
-HISTORY_MSG_510;L*a*b Spot transit
+HISTORY_MSG_510;L*a*b Spot transition
 HISTORY_MSG_511;L*a*b Spot thresh
 HISTORY_MSG_512;L*a*b Spot deltaE-weakening
 HISTORY_MSG_513;L*a*b Spot scope
@@ -909,6 +909,7 @@ HISTORY_MSG_655;Local - SH mask slope
 HISTORY_MSG_656;Local - Color soft radius
 HISTORY_MSG_657;Local - Retinex soft radius
 HISTORY_MSG_658;Local - CBDL soft radius
+HISTORY_MSG_659;L*a*b Spot transition-weakening
 HISTORY_MSG_CLAMPOOG;Clip out-of-gamut colors
 HISTORY_MSG_COLORTONING_LABGRID_VALUE;CT - Color correction
 HISTORY_MSG_COLORTONING_LABREGION_AB;CT - Color correction
@@ -2121,6 +2122,9 @@ TP_LOCALLAB_SYM;Symmetrical (mouse)
 TP_LOCALLAB_CURVEEDITOR_TONES_LABEL;Tone curve
 TP_LOCALLAB_TRANSIT;Transition
 TP_LOCALLAB_TRANSIT_TOOLTIP;Adjust smoothness of transition between affected and unaffected areas.
+TP_LOCALLAB_TRANSITVALUE;Transition value
+TP_LOCALLAB_TRANSITWEAK;Transition weakening
+TP_LOCALLAB_TRANSITWEAK_TOOLTIP;Adjust weakening : change smoothness process - 1 linear - 2 parabolic - 3 cubic  
 TP_LOCALLAB_VIBRANCE;Vibrance
 TP_LOCALLAB_WARM;Warm - Cool & Color artifacts
 TP_LOCALLAB_WARM_TOOLTIP;This slider use Ciecam algorithm and acts as White Balance, it can warm or cool the area selected.\nIt can also in some cases reduce color artifacts.
diff --git a/rtengine/iplocallab.cc b/rtengine/iplocallab.cc
index 317d3c6cb..af637019d 100644
--- a/rtengine/iplocallab.cc
+++ b/rtengine/iplocallab.cc
@@ -184,6 +184,7 @@ struct local_params {
     double rad;
     double stren;
     int trans;
+    float transweak;
     int dehaze;
     bool inv;
     bool invex;
@@ -519,6 +520,7 @@ static void calcLocalParams(int sp, int oW, int oH, const LocallabParams& locall
     float blurcolor = (float) locallab.spots.at(sp).blurcolde;
     float blurSH = (float) locallab.spots.at(sp).blurSHde;
     int local_transit = locallab.spots.at(sp).transit;
+    float local_transitweak = (float)locallab.spots.at(sp).transitweak;
     float radius = (float) locallab.spots.at(sp).radius;
     double sharradius = ((double) locallab.spots.at(sp).sharradius);
     sharradius = CLIP42_35(sharradius);
@@ -610,6 +612,7 @@ static void calcLocalParams(int sp, int oW, int oH, const LocallabParams& locall
     }
 
     lp.trans = local_transit;
+    lp.transweak = local_transitweak;
     lp.rad = radius;
     lp.stren = strength;
     lp.sensbn = local_sensibn;
@@ -706,6 +709,7 @@ static void calcTransitionrect(const float lox, const float loy, const float ach
         } else {
             zone = 1;
             localFactor = calcLocalFactorrect(lox, loy, lp.xc, lp.lx, lp.yc, lp.ly, ach);
+            localFactor = pow(localFactor, lp.transweak);
         }
 
     } else if (lox >= lp.xc && lox < lp.xc + lp.lx && loy < lp.yc && loy > lp.yc - lp.lyT) {
@@ -714,6 +718,7 @@ static void calcTransitionrect(const float lox, const float loy, const float ach
         } else {
             zone = 1;
             localFactor = calcLocalFactorrect(lox, loy, lp.xc, lp.lx, lp.yc, lp.lyT, ach);
+            localFactor = pow(localFactor, lp.transweak);
         }
 
 
@@ -723,6 +728,7 @@ static void calcTransitionrect(const float lox, const float loy, const float ach
         } else {
             zone = 1;
             localFactor = calcLocalFactorrect(lox, loy, lp.xc, lp.lxL, lp.yc, lp.lyT, ach);
+            localFactor = pow(localFactor, lp.transweak);
         }
 
     } else if (lox < lp.xc && lox > lp.xc - lp.lxL && loy > lp.yc && loy < lp.yc + lp.ly) {
@@ -731,6 +737,7 @@ static void calcTransitionrect(const float lox, const float loy, const float ach
         } else {
             zone = 1;
             localFactor = calcLocalFactorrect(lox, loy, lp.xc, lp.lxL, lp.yc, lp.ly, ach);
+            localFactor = pow(localFactor, lp.transweak);
         }
 
     }
@@ -755,6 +762,7 @@ static void calcTransition(const float lox, const float loy, const float ach, co
 
             if (zone) {
                 localFactor = calcLocalFactor(lox, loy, lp.xc, lp.lx, lp.yc, lp.ly, ach);
+                localFactor = pow(localFactor, lp.transweak);
             }
         }
     } else if (lox >= lp.xc && lox < lp.xc + lp.lx && loy < lp.yc && loy > lp.yc - lp.lyT) {
@@ -766,6 +774,7 @@ static void calcTransition(const float lox, const float loy, const float ach, co
 
             if (zone) {
                 localFactor = calcLocalFactor(lox, loy, lp.xc, lp.lx, lp.yc, lp.lyT, ach);
+                localFactor = pow(localFactor, lp.transweak);
             }
         }
     } else if (lox < lp.xc && lox > lp.xc - lp.lxL && loy <= lp.yc && loy > lp.yc - lp.lyT) {
@@ -777,6 +786,7 @@ static void calcTransition(const float lox, const float loy, const float ach, co
 
             if (zone) {
                 localFactor = calcLocalFactor(lox, loy, lp.xc, lp.lxL, lp.yc, lp.lyT, ach);
+                localFactor = pow(localFactor, lp.transweak);
             }
         }
     } else if (lox < lp.xc && lox > lp.xc - lp.lxL && loy > lp.yc && loy < lp.yc + lp.ly) {
@@ -788,6 +798,7 @@ static void calcTransition(const float lox, const float loy, const float ach, co
 
             if (zone) {
                 localFactor = calcLocalFactor(lox, loy, lp.xc, lp.lxL, lp.yc, lp.ly, ach);
+                localFactor = pow(localFactor, lp.transweak);
             }
         }
     }
diff --git a/rtengine/procevents.h b/rtengine/procevents.h
index c7c82b890..3f20ac273 100644
--- a/rtengine/procevents.h
+++ b/rtengine/procevents.h
@@ -685,6 +685,7 @@ enum ProcEventCode {
     Evlocallabsoftradiuscol = 655,
     Evlocallabsoftradiusret = 656,
     Evlocallabsoftradiuscb = 657,
+    EvLocallabSpotTransitweak = 658,
 
     NUMOFEVENTS
 };
diff --git a/rtengine/procparams.cc b/rtengine/procparams.cc
index aa3dc3598..bdda44411 100644
--- a/rtengine/procparams.cc
+++ b/rtengine/procparams.cc
@@ -2357,6 +2357,7 @@ LocallabParams::LocallabSpot::LocallabSpot() :
     thresh(2.0),
     iter(2.0),
     balan(1.0),
+    transitweak(1.0),
     avoid(false),
     // Color & Light
     expcolor(false),
@@ -2537,6 +2538,7 @@ bool LocallabParams::LocallabSpot::operator ==(const LocallabSpot& other) const
         && thresh == other.thresh
         && iter == other.iter
         && balan == other.balan
+        && transitweak == other.transitweak
         && avoid == other.avoid
         // Color & Light
         && expcolor == other.expcolor
@@ -3673,6 +3675,7 @@ int ProcParams::save(const Glib::ustring& fname, const Glib::ustring& fname2, bo
                 saveToKeyfile(!pedited || pedited->locallab.spots.at(i).thresh, "Locallab", "Thresh_" + std::to_string(i), spot.thresh, keyFile);
                 saveToKeyfile(!pedited || pedited->locallab.spots.at(i).iter, "Locallab", "Iter_" + std::to_string(i), spot.iter, keyFile);
                 saveToKeyfile(!pedited || pedited->locallab.spots.at(i).balan, "Locallab", "Balan_" + std::to_string(i), spot.balan, keyFile);
+                saveToKeyfile(!pedited || pedited->locallab.spots.at(i).transitweak, "Locallab", "Transitweak_" + std::to_string(i), spot.transitweak, keyFile);
                 saveToKeyfile(!pedited || pedited->locallab.spots.at(i).avoid, "Locallab", "Avoid_" + std::to_string(i), spot.avoid, keyFile);
                 // Color & Light
                 saveToKeyfile(!pedited || pedited->locallab.spots.at(i).expcolor, "Locallab", "Expcolor_" + std::to_string(i), spot.expcolor, keyFile);
@@ -4938,6 +4941,7 @@ int ProcParams::load(const Glib::ustring& fname, ParamsEdited* pedited)
                 assignFromKeyfile(keyFile, "Locallab", "Thresh_" + std::to_string(i), pedited, spot.thresh, spotEdited.thresh);
                 assignFromKeyfile(keyFile, "Locallab", "Iter_" + std::to_string(i), pedited, spot.iter, spotEdited.iter);
                 assignFromKeyfile(keyFile, "Locallab", "Balan_" + std::to_string(i), pedited, spot.balan, spotEdited.balan);
+                assignFromKeyfile(keyFile, "Locallab", "Transitweak_" + std::to_string(i), pedited, spot.transitweak, spotEdited.transitweak);
                 assignFromKeyfile(keyFile, "Locallab", "Avoid_" + std::to_string(i), pedited, spot.avoid, spotEdited.avoid);
                 // Color & Light
                 assignFromKeyfile(keyFile, "Locallab", "Expcolor_" + std::to_string(i), pedited, spot.expcolor, spotEdited.expcolor);
diff --git a/rtengine/procparams.h b/rtengine/procparams.h
index 0af821e71..8c032ed6c 100644
--- a/rtengine/procparams.h
+++ b/rtengine/procparams.h
@@ -957,6 +957,7 @@ struct LocallabParams {
         double thresh;
         double iter;
         double balan;
+        double transitweak;
         bool avoid;
         // Color & Light
         bool expcolor;
diff --git a/rtengine/refreshmap.cc b/rtengine/refreshmap.cc
index d3dc43d60..6bdce4598 100644
--- a/rtengine/refreshmap.cc
+++ b/rtengine/refreshmap.cc
@@ -684,7 +684,8 @@ int refreshmap[rtengine::NUMOFEVENTS] = {
     LUMINANCECURVE,      //EvLocallabslomaskSH
     LUMINANCECURVE,      //EvLocallabsoftradiuscol
     LUMINANCECURVE,      //EvLocallabsoftradiusret
-    LUMINANCECURVE      //EvLocallabsoftradiuscb
+    LUMINANCECURVE,      //EvLocallabsoftradiuscb
+    LUMINANCECURVE   // EvLocallabSpotTransitweak
 };
 
 
diff --git a/rtgui/controlspotpanel.cc b/rtgui/controlspotpanel.cc
index f06280768..d1d851fe4 100644
--- a/rtgui/controlspotpanel.cc
+++ b/rtgui/controlspotpanel.cc
@@ -57,10 +57,11 @@ ControlSpotPanel::ControlSpotPanel():
     centerX_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_CENTER_X"), -1000, 1000, 1, 0))),
     centerY_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_CENTER_Y"), -1000, 1000, 1, 0))),
     circrad_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_CIRCRADIUS"), 2, 150, 1, 18))),
-    transit_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_TRANSIT"), 5, 95, 1, 60))),
+    transit_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_TRANSITVALUE"), 5, 95, 1, 60))),
     thresh_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_THRESDELTAE"), 0.0, 8.0, 0.1, 2.0))),
     iter_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_PROXI"), 0.2, 4.0, 0.1, 2.0))),
     balan_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_BALAN"), 0.3, 1.7, 0.1, 1.0, Gtk::manage(new RTImage("rawtherapee-logo-16.png")), Gtk::manage(new RTImage("circle-white-small.png"))))),
+    transitweak_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_TRANSITWEAK"), 0.5, 4.0, 0.1, 1.0))),
 
     avoid_(Gtk::manage(new Gtk::CheckButton(M("TP_LOCALLAB_AVOID")))),
 
@@ -227,9 +228,20 @@ ControlSpotPanel::ControlSpotPanel():
     ctboxqualitymethod->pack_start(*qualityMethod_);
     pack_start(*ctboxqualitymethod);
 
-    pack_start(*transit_);
+    Gtk::Frame* const transitFrame = Gtk::manage(new Gtk::Frame(M("TP_LOCALLAB_TRANSIT")));
+    transitFrame->set_label_align(0.025, 0.5);
+    transitFrame->set_tooltip_text(M("TP_LOCALLAB_TRANSIT_TOOLTIP"));
+    ToolParamBlock* const transitBox = Gtk::manage(new ToolParamBlock());
     transit_->set_tooltip_text(M("TP_LOCALLAB_TRANSIT_TOOLTIP"));
+    transitweak_->set_tooltip_text(M("TP_LOCALLAB_TRANSITWEAK_TOOLTIP"));
     transit_->setAdjusterListener(this);
+    transitweak_->setAdjusterListener(this);
+
+    transitBox->pack_start(*transit_);
+    transitBox->pack_start(*transitweak_);
+    transitFrame->add(*transitBox);
+    pack_start(*transitFrame);
+    
 
     Gtk::Frame* const artifFrame = Gtk::manage(new Gtk::Frame(M("TP_LOCALLAB_ARTIF")));
     artifFrame->set_label_align(0.025, 0.5);
@@ -487,6 +499,7 @@ void ControlSpotPanel::load_ControlSpot_param()
     thresh_->setValue(static_cast<double>(row[spots_.thresh]));
     iter_->setValue(static_cast<double>(row[spots_.iter]));
     balan_->setValue(static_cast<double>(row[spots_.balan]));
+    transitweak_->setValue(static_cast<double>(row[spots_.transitweak]));
     avoid_->set_active(row[spots_.avoid]);
 }
 
@@ -875,6 +888,7 @@ void ControlSpotPanel::adjusterChanged(Adjuster* a, double newval)
         }
     }
 
+
     if (a == thresh_) {
         row[spots_.thresh] = thresh_->getValue();
 
@@ -899,7 +913,15 @@ void ControlSpotPanel::adjusterChanged(Adjuster* a, double newval)
             listener->panelChanged(EvLocallabSpotbalan, balan_->getTextValue());
         }
     }
-    
+
+    if (a == transitweak_) {
+        row[spots_.transitweak] = transitweak_->getValue();
+
+        if (listener) {
+            listener->panelChanged(EvLocallabSpotTransitweak, transitweak_->getTextValue());
+        }
+    }
+
 }
 
 void ControlSpotPanel::avoidChanged()
@@ -965,6 +987,7 @@ void ControlSpotPanel::disableParamlistener(bool cond)
     thresh_->block(cond);
     iter_->block(cond);
     balan_->block(cond);
+    transitweak_->block(cond);
     avoidConn_.block(cond);
 }
 
@@ -990,6 +1013,7 @@ void ControlSpotPanel::setParamEditable(bool cond)
     thresh_->set_sensitive(cond);
     iter_->set_sensitive(cond);
     balan_->set_sensitive(cond);
+    transitweak_->set_sensitive(cond);
     avoid_->set_sensitive(cond);
 }
 
@@ -1695,6 +1719,7 @@ ControlSpotPanel::SpotRow* ControlSpotPanel::getSpot(int id)
             r->thresh = row[spots_.thresh];
             r->iter = row[spots_.iter];
             r->balan = row[spots_.balan];
+            r->transitweak = row[spots_.transitweak];
             r->avoid = row[spots_.avoid];
 
             return r;
@@ -1817,6 +1842,7 @@ void ControlSpotPanel::addControlSpot(SpotRow* newSpot)
     row[spots_.thresh] = newSpot->thresh;
     row[spots_.iter] = newSpot->iter;
     row[spots_.balan] = newSpot->balan;
+    row[spots_.transitweak] = newSpot->transitweak;
     row[spots_.avoid] = newSpot->avoid;
     updateParamVisibility();
     disableParamlistener(false);
@@ -1861,6 +1887,7 @@ int ControlSpotPanel::updateControlSpot(SpotRow* spot)
             row[spots_.thresh] = spot->thresh;
             row[spots_.iter] = spot->iter;
             row[spots_.balan] = spot->balan;
+            row[spots_.transitweak] = spot->transitweak;
             row[spots_.avoid] = spot->avoid;
 
             updateControlSpotCurve(row);
@@ -1951,6 +1978,7 @@ ControlSpotPanel::SpotEdited* ControlSpotPanel::getEditedStates()
     se->thresh = thresh_->getEditedState();
     se->iter = iter_->getEditedState();
     se->balan = balan_->getEditedState();
+    se->transitweak = transitweak_->getEditedState();
     se->avoid = !avoid_->get_inconsistent();
 
     return se;
@@ -2018,6 +2046,7 @@ void ControlSpotPanel::setEditedStates(SpotEdited* se)
     thresh_->setEditedState(se->thresh ? Edited : UnEdited);
     iter_->setEditedState(se->iter ? Edited : UnEdited);
     balan_->setEditedState(se->balan ? Edited : UnEdited);
+    transitweak_->setEditedState(se->transitweak ? Edited : UnEdited);
     avoid_->set_inconsistent(multiImage && !se->avoid);
 
     // Update Control Spot GUI according to widgets edited states
@@ -2061,6 +2090,7 @@ void ControlSpotPanel::setDefaults(const rtengine::procparams::ProcParams * defP
     thresh_->setDefault(defSpot->thresh);
     iter_->setDefault(defSpot->iter);
     balan_->setDefault(defSpot->balan);
+    transitweak_->setDefault(defSpot->transitweak);
 
     // Set default edited states for adjusters
     if (!pedited) {
@@ -2078,6 +2108,7 @@ void ControlSpotPanel::setDefaults(const rtengine::procparams::ProcParams * defP
         thresh_->setDefaultEditedState(Irrelevant);
         iter_->setDefaultEditedState(Irrelevant);
         balan_->setDefaultEditedState(Irrelevant);
+        transitweak_->setDefaultEditedState(Irrelevant);
     } else {
         const LocallabParamsEdited::LocallabSpotEdited* defSpotState = new LocallabParamsEdited::LocallabSpotEdited(true);
 
@@ -2099,6 +2130,7 @@ void ControlSpotPanel::setDefaults(const rtengine::procparams::ProcParams * defP
         thresh_->setDefaultEditedState(defSpotState->thresh ? Edited : UnEdited);
         iter_->setDefaultEditedState(defSpotState->iter ? Edited : UnEdited);
         balan_->setDefaultEditedState(defSpotState->balan ? Edited : UnEdited);
+        transitweak_->setDefaultEditedState(defSpotState->transitweak ? Edited : UnEdited);
     }
 }
 
@@ -2121,6 +2153,7 @@ void ControlSpotPanel::setBatchMode(bool batchMode)
     thresh_->showEditedCB();
     iter_->showEditedCB();
     balan_->showEditedCB();
+    transitweak_->showEditedCB();
 
     // Set batch mode for comboBoxText
     shape_->append(M("GENERAL_UNCHANGED"));
@@ -2158,6 +2191,7 @@ ControlSpotPanel::ControlSpots::ControlSpots()
     add(thresh);
     add(iter);
     add(balan);
+    add(transitweak);
     add(avoid);
 }
 
diff --git a/rtgui/controlspotpanel.h b/rtgui/controlspotpanel.h
index c43384ed5..0c9e72d25 100644
--- a/rtgui/controlspotpanel.h
+++ b/rtgui/controlspotpanel.h
@@ -63,6 +63,7 @@ public:
         double thresh;
         double iter;
         double balan;
+        double transitweak;
         bool avoid;
     };
 
@@ -92,6 +93,7 @@ public:
         bool thresh;
         bool iter;
         bool balan;
+        bool transitweak;
         bool avoid;
     };
 
@@ -283,6 +285,7 @@ private:
         Gtk::TreeModelColumn<double> thresh;
         Gtk::TreeModelColumn<double> iter;
         Gtk::TreeModelColumn<double> balan;
+        Gtk::TreeModelColumn<double> transitweak;
         Gtk::TreeModelColumn<bool> avoid;
     };
 
@@ -340,6 +343,7 @@ private:
     Adjuster* const thresh_;
     Adjuster* const iter_;
     Adjuster* const balan_;
+    Adjuster* const transitweak_;
 
     Gtk::CheckButton* const avoid_;
     sigc::connection avoidConn_;
diff --git a/rtgui/locallab.cc b/rtgui/locallab.cc
index 1e9b95385..8c403a32c 100644
--- a/rtgui/locallab.cc
+++ b/rtgui/locallab.cc
@@ -1303,6 +1303,7 @@ void Locallab::read(const ProcParams* pp, const ParamsEdited* pedited)
         r->thresh = pp->locallab.spots.at(i).thresh;
         r->iter = pp->locallab.spots.at(i).iter;
         r->balan = pp->locallab.spots.at(i).balan;
+        r->transitweak = pp->locallab.spots.at(i).transitweak;
         r->avoid = pp->locallab.spots.at(i).avoid;
 
         expsettings->addControlSpot(r);
@@ -1404,6 +1405,7 @@ void Locallab::write(ProcParams* pp, ParamsEdited* pedited)
             r->thresh = newSpot->thresh;
             r->iter = newSpot->iter;
             r->balan = newSpot->balan;
+            r->transitweak = newSpot->transitweak;
             r->avoid = newSpot->avoid;
             expsettings->addControlSpot(r);
 
@@ -1591,6 +1593,7 @@ void Locallab::write(ProcParams* pp, ParamsEdited* pedited)
             r->thresh = newSpot->thresh;
             r->iter = newSpot->iter;
             r->balan = newSpot->balan;
+            r->transitweak = newSpot->transitweak;
             r->avoid = newSpot->avoid;
             expsettings->addControlSpot(r);
 
@@ -1680,6 +1683,7 @@ void Locallab::write(ProcParams* pp, ParamsEdited* pedited)
                     pp->locallab.spots.at(pp->locallab.selspot).thresh = r->thresh;
                     pp->locallab.spots.at(pp->locallab.selspot).iter = r->iter;
                     pp->locallab.spots.at(pp->locallab.selspot).balan = r->balan;
+                    pp->locallab.spots.at(pp->locallab.selspot).transitweak = r->transitweak;
                     pp->locallab.spots.at(pp->locallab.selspot).avoid = r->avoid;
                     // Color & Light
                     pp->locallab.spots.at(pp->locallab.selspot).expcolor = expcolor->getEnabled();
@@ -1889,6 +1893,7 @@ void Locallab::write(ProcParams* pp, ParamsEdited* pedited)
                         pe->locallab.spots.at(pp->locallab.selspot).transit = pe->locallab.spots.at(pp->locallab.selspot).transit || se->transit;
                         pe->locallab.spots.at(pp->locallab.selspot).thresh = pe->locallab.spots.at(pp->locallab.selspot).thresh || se->thresh;
                         pe->locallab.spots.at(pp->locallab.selspot).iter = pe->locallab.spots.at(pp->locallab.selspot).iter || se->iter;
+                        pe->locallab.spots.at(pp->locallab.selspot).transitweak = pe->locallab.spots.at(pp->locallab.selspot).transitweak || se->transitweak;
                         pe->locallab.spots.at(pp->locallab.selspot).balan = pe->locallab.spots.at(pp->locallab.selspot).balan || se->balan;
                         pe->locallab.spots.at(pp->locallab.selspot).avoid = pe->locallab.spots.at(pp->locallab.selspot).avoid || se->avoid;
                         // Color & Light
@@ -2072,6 +2077,7 @@ void Locallab::write(ProcParams* pp, ParamsEdited* pedited)
                         pedited->locallab.spots.at(pp->locallab.selspot).thresh = pedited->locallab.spots.at(pp->locallab.selspot).thresh || se->thresh;
                         pedited->locallab.spots.at(pp->locallab.selspot).iter = pedited->locallab.spots.at(pp->locallab.selspot).iter || se->iter;
                         pedited->locallab.spots.at(pp->locallab.selspot).balan = pedited->locallab.spots.at(pp->locallab.selspot).balan || se->balan;
+                        pedited->locallab.spots.at(pp->locallab.selspot).transitweak = pedited->locallab.spots.at(pp->locallab.selspot).transitweak || se->transitweak;
                         pedited->locallab.spots.at(pp->locallab.selspot).avoid = pedited->locallab.spots.at(pp->locallab.selspot).avoid || se->avoid;
                         // Color & Light
                         pedited->locallab.spots.at(pp->locallab.selspot).expcolor = pedited->locallab.spots.at(pp->locallab.selspot).expcolor || !expcolor->get_inconsistent();
@@ -4569,6 +4575,7 @@ void Locallab::updateLocallabGUI(const rtengine::procparams::ProcParams* pp, con
                 se->thresh = spotState->thresh;
                 se->iter = spotState->iter;
                 se->balan = spotState->balan;
+                se->transitweak = spotState->transitweak;
                 se->avoid = spotState->avoid;
                 expsettings->setEditedStates(se);
 
diff --git a/rtgui/paramsedited.cc b/rtgui/paramsedited.cc
index 00a35ed11..df2037dba 100644
--- a/rtgui/paramsedited.cc
+++ b/rtgui/paramsedited.cc
@@ -947,6 +947,7 @@ void ParamsEdited::initFrom(const std::vector<rtengine::procparams::ProcParams>&
                 locallab.spots.at(j).thresh = locallab.spots.at(j).thresh && pSpot.thresh == otherSpot.thresh;
                 locallab.spots.at(j).iter = locallab.spots.at(j).iter && pSpot.iter == otherSpot.iter;
                 locallab.spots.at(j).balan = locallab.spots.at(j).balan && pSpot.balan == otherSpot.balan;
+                locallab.spots.at(j).transitweak = locallab.spots.at(j).transitweak && pSpot.transitweak == otherSpot.transitweak;
                 locallab.spots.at(j).avoid = locallab.spots.at(j).avoid && pSpot.avoid == otherSpot.avoid;
                 // Color & Light
                 locallab.spots.at(j).expcolor = locallab.spots.at(j).expcolor && pSpot.expcolor == otherSpot.expcolor;
@@ -2596,6 +2597,7 @@ void ParamsEdited::combine(rtengine::procparams::ProcParams& toEdit, const rteng
             toEdit.locallab.spots.at(i).transit = mods.locallab.spots.at(i).transit;
         }
 
+
         if (locallab.spots.at(i).thresh) {
             toEdit.locallab.spots.at(i).thresh = mods.locallab.spots.at(i).thresh;
         }
@@ -2608,6 +2610,10 @@ void ParamsEdited::combine(rtengine::procparams::ProcParams& toEdit, const rteng
             toEdit.locallab.spots.at(i).balan = mods.locallab.spots.at(i).balan;
         }
 
+        if (locallab.spots.at(i).transitweak) {
+            toEdit.locallab.spots.at(i).transitweak = mods.locallab.spots.at(i).transitweak;
+        }
+
         if (locallab.spots.at(i).avoid) {
             toEdit.locallab.spots.at(i).avoid = mods.locallab.spots.at(i).avoid;
         }
@@ -4139,6 +4145,7 @@ LocallabParamsEdited::LocallabSpotEdited::LocallabSpotEdited(bool v) :
     thresh(v),
     iter(v),
     balan(v),
+    transitweak(v),
     avoid(v),
     // Color & Light
     expcolor(v),
@@ -4316,6 +4323,7 @@ void LocallabParamsEdited::LocallabSpotEdited::set(bool v)
     thresh = v;
     iter = v;
     balan = v;
+    transitweak = v;
     avoid = v;
     // Color & Light
     expcolor = v;
diff --git a/rtgui/paramsedited.h b/rtgui/paramsedited.h
index 21ba52f4d..411b90867 100644
--- a/rtgui/paramsedited.h
+++ b/rtgui/paramsedited.h
@@ -374,6 +374,7 @@ public:
         bool thresh;
         bool iter;
         bool balan;
+        bool transitweak;
         bool avoid;
         // Color & Light
         bool expcolor;