Index: src/jalview/bin/HiDPISetting.java
===================================================================
diff -u -N -r07d425923a64af71ce7d41a11061abd537e99276 -rb7510c12a0fb9028617e25a4b6edb3cc4011142f
--- src/jalview/bin/HiDPISetting.java	(.../HiDPISetting.java)	(revision 07d425923a64af71ce7d41a11061abd537e99276)
+++ src/jalview/bin/HiDPISetting.java	(.../HiDPISetting.java)	(revision b7510c12a0fb9028617e25a4b6edb3cc4011142f)
@@ -68,16 +68,31 @@
 
     // get and use command line property values first
     String setHiDPIProperty = System.getProperty(setHiDPIPropertyName);
-    setHiDPI = setHiDPIProperty != null
-            && setHiDPIProperty.equalsIgnoreCase("true");
+    boolean setHiDPIPropertyBool = Boolean.parseBoolean(setHiDPIProperty);
 
+    // allow -DsetHiDPI=false to turn off HiDPI scaling
+    if (setHiDPIProperty != null && !setHiDPIPropertyBool)
+    {
+      clear();
+      doneInit = true;
+      return;
+    }
+
+    setHiDPI = setHiDPIProperty != null && setHiDPIPropertyBool;
+
     String setHiDPIScaleProperty = System
             .getProperty(setHiDPIScalePropertyName);
     if (setHiDPIScaleProperty != null)
     {
       try
       {
         setHiDPIScale = Integer.parseInt(setHiDPIScaleProperty);
+        // if setHiDPIScale property is validly set and setHiDPI property wasn't
+        // attempted to be set we assume setHiDPIScale to be true
+        if (setHiDPIProperty == null)
+        {
+          setHiDPI = true;
+        }
       } catch (NumberFormatException e)
       {
         System.err.println(setHiDPIScalePropertyName + " property give ("