diff --git a/rtengine/iplocallab.cc b/rtengine/iplocallab.cc
index 51d033e4e..e8fe341ec 100644
--- a/rtengine/iplocallab.cc
+++ b/rtengine/iplocallab.cc
@@ -6507,7 +6507,13 @@ void ImProcFunctions::transit_shapedetect2(int call, int senstype, const LabImag
                         transformed->b[y + ystart][x + xstart] = CLIPC(difb);
                     } else if (previewexp || previewvib || previewcol || previewSH || previewtm || previewlc) {//show deltaE
                         difb = reducdE * 10000.f * lp.colorde;
-                    
+                        float darklim = 5000.f;
+                        if(transformed->L[y + ystart][x + xstart] < darklim) {//enhance dark luminance as user can see!
+                            float dark = transformed->L[y + ystart][x + xstart];
+                            float aa = -1.f;
+                            float bb = darklim;
+                            transformed->L[y + ystart][x + xstart] = dark * aa + bb;
+                        }
                         if(lp.colorde <= 0) {
                             transformed->a[y + ystart][x + xstart] = 0.f;
                             transformed->b[y + ystart][x + xstart] = difb;
diff --git a/rtgui/controlspotpanel.cc b/rtgui/controlspotpanel.cc
index 8b17d7148..777db7553 100644
--- a/rtgui/controlspotpanel.cc
+++ b/rtgui/controlspotpanel.cc
@@ -70,7 +70,7 @@ ControlSpotPanel::ControlSpotPanel():
     iter_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_PROXI"), 0.2, 10.0, 0.1, 2.0))),
     balan_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_BALAN"), 0.2, 2.5, 0.1, 1.0, Gtk::manage(new RTImage("rawtherapee-logo-16.png")), Gtk::manage(new RTImage("circle-white-small.png"))))),
     balanh_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_BALANH"), 0.2, 2.5, 0.1, 1.0, Gtk::manage(new RTImage("rawtherapee-logo-16.png")),Gtk::manage(new RTImage("circle-red-green-small.png"))))),
-    colorde_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_COLORDE"), -11, 11, 2, -5, Gtk::manage(new RTImage("circle-blue-small.png")),Gtk::manage(new RTImage("circle-green-small.png"))))),
+    colorde_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_COLORDE"), -15, 15, 2, -5, Gtk::manage(new RTImage("circle-blue-small.png")),Gtk::manage(new RTImage("circle-green-small.png"))))),
     transitweak_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_TRANSITWEAK"), 0.5, 15.0, 0.1, 1.0))),
     transitgrad_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_TRANSITGRAD"), -1.0, 1.0, 0.01, 0.0))),
     scopemask_(Gtk::manage(new Adjuster(M("TP_LOCALLAB_SCOPEMASK"), 0, 100, 1, 60))),
diff --git a/rtgui/locallab.cc b/rtgui/locallab.cc
index 6b4f79c6e..2500ce086 100644
--- a/rtgui/locallab.cc
+++ b/rtgui/locallab.cc
@@ -482,7 +482,7 @@ detailSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_DETAILSH"), -5, 5, 1, 0))),
 fatamountSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_FATAMOUNT"), 1., 100., 1., 1.))),
 fatanchorSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_FATANCHOR"), 1., 100., 1., 50., Gtk::manage(new RTImage("circle-black-small.png")), Gtk::manage(new RTImage("circle-white-small.png"))))),
 gamSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_GAMSH"), 0.25, 15.0, 0.01, 2.4))),
-sloSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_SLOSH"), 0.0, 100.0, 0.01, 12.92))),
+sloSH(Gtk::manage(new Adjuster(M("TP_LOCALLAB_SLOSH"), 0.0, 150.0, 0.01, 12.92))),
 // Vibrance
 saturated(Gtk::manage(new Adjuster(M("TP_VIBRANCE_SATURATED"), -100., 100., 1., 0.))),
 pastels(Gtk::manage(new Adjuster(M("TP_VIBRANCE_PASTELS"), -100., 100., 1., 0.))),