diff --git a/Code/Mantid/MantidQt/SliceViewer/src/ColorBarWidget.cpp b/Code/Mantid/MantidQt/SliceViewer/src/ColorBarWidget.cpp
index e21a726051e01d101ffa1f429f5eaf66e3938cd3..ab398d58d8cbbd17d449692e06fd88fa761fc132 100644
--- a/Code/Mantid/MantidQt/SliceViewer/src/ColorBarWidget.cpp
+++ b/Code/Mantid/MantidQt/SliceViewer/src/ColorBarWidget.cpp
@@ -34,6 +34,7 @@ ColorBarWidget::ColorBarWidget(QWidget *parent)
   ui.cmbScaleType->addItem(tr("logarithmic"));
   ui.cmbScaleType->addItem(tr("power"));
   m_colorMap.changeScaleType( GraphOptions::Linear );
+  ui.dspnN->setMinimum(-100.0);
   ui.dspnN->setEnabled(false);
 
   // Create and add the color bar