diff --git a/js/backend.admin.js b/js/backend.admin.js
index 8df40cac9898d62c75ed9a705b74cf0f140d1166..99222ba56246b57190c6d7bff3b8c8db88a789e8 100644
--- a/js/backend.admin.js
+++ b/js/backend.admin.js
@@ -1921,6 +1921,7 @@ Pianos4Backend.ImageManager = function( parent, params )
         var suspected_resolution = parseInt( img.resolution );
         var ruler_offset = 0;
         var ruler_mirror = false;
+        var img_ratio = null;
         
         var draw_ruler = function()
         {
@@ -1943,6 +1944,7 @@ Pianos4Backend.ImageManager = function( parent, params )
                     $( "#gruler" )
                         .attr( "transform", "scale( " + suspected_resolution / 25.4 / ruler_size_px_per_mm + " ) translate( " + ruler_start_x + " " + ruler_start_y + " ) rotate( " + angle + " ) translate( " + ruler_offset + " -1 ) translate( 0 2 ) scale( 1 -1 )" );
                 }
+                console.log( suspected_resolution / img_ratio );
             }
         }
         
@@ -1953,7 +1955,7 @@ Pianos4Backend.ImageManager = function( parent, params )
             
             var ratio_width = $( "#image_editor_img_svg > svg" ).width() / img.width;
             var ratio_height = $( "#image_editor_img_svg > svg" ).height() / img.height;
-            var ratio = Math.min( ratio_width, ratio_height );
+            img_ratio = Math.min( ratio_width, ratio_height );
             
             $( "#gruler" )
                 .on( "click", function( event )