diff --git a/backend/lexmark.c b/backend/lexmark.c
index e91b07694..1d25b1f42 100644
--- a/backend/lexmark.c
+++ b/backend/lexmark.c
@@ -1059,6 +1059,7 @@ sane_start (SANE_Handle handle)
   Lexmark_Device *lexmark_device;
   SANE_Int offset;
   SANE_Status status;
+  int resolution;
 
   DBG (2, "sane_start: handle=%p\n", (void *) handle);
 
@@ -1110,8 +1111,13 @@ sane_start (SANE_Handle handle)
       sanei_lexmark_low_search_home_bwd (lexmark_device);
     }
 
-  /* do calibration before offset detection */
-  sanei_lexmark_low_set_scan_regs (lexmark_device, 0, SANE_FALSE);
+  /* do calibration before offset detection , use sensor max dpi, not motor's one */
+  resolution = lexmark_device->val[OPT_RESOLUTION].w;
+  if(resolution > 600)
+  {
+	  resolution = 600;
+  }
+  sanei_lexmark_low_set_scan_regs (lexmark_device, resolution, 0, SANE_FALSE);
   status = sanei_lexmark_low_calibration (lexmark_device);
   if (status != SANE_STATUS_GOOD)
     {
@@ -1131,7 +1137,7 @@ sane_start (SANE_Handle handle)
   /* Set the shadow registers for scan with the options (resolution, mode, 
      size) set in the front end. Pass the offset so we can get the vert.
      start. */
-  sanei_lexmark_low_set_scan_regs (lexmark_device, offset, SANE_TRUE);
+  sanei_lexmark_low_set_scan_regs (lexmark_device, lexmark_device->val[OPT_RESOLUTION].w, offset, SANE_TRUE);
   
   if (sanei_lexmark_low_start_scan (lexmark_device) == SANE_STATUS_GOOD)
     {
diff --git a/backend/lexmark.h b/backend/lexmark.h
index 752e2f96f..b75bb0e0e 100644
--- a/backend/lexmark.h
+++ b/backend/lexmark.h
@@ -251,6 +251,7 @@ void sanei_lexmark_low_move_fwd (SANE_Int distance, Lexmark_Device * dev,
 SANE_Bool sanei_lexmark_low_search_home_bwd (Lexmark_Device * dev);
 SANE_Int sanei_lexmark_low_find_start_line (Lexmark_Device * dev);
 SANE_Status sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev,
+					       SANE_Int resolution,
 					       SANE_Int offset,
 					       SANE_Bool calibrated);
 SANE_Status sanei_lexmark_low_start_scan (Lexmark_Device * dev);
diff --git a/backend/lexmark_low.c b/backend/lexmark_low.c
index be3a137b4..744b04f59 100644
--- a/backend/lexmark_low.c
+++ b/backend/lexmark_low.c
@@ -2552,17 +2552,14 @@ sanei_lexmark_low_find_start_line (Lexmark_Device * dev)
 
 
 SANE_Status
-sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
+sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int resolution, SANE_Int offset,
 				   SANE_Bool calibrated)
 {
-  SANE_Int yres;
   SANE_Bool isColourScan;
 
   DBG (2, "sanei_lexmark_low_set_scan_regs:\n");
-  /* resolution */
-  yres = dev->val[OPT_RESOLUTION].w;
 
-  DBG (7, "sanei_lexmark_low_set_scan_regs: yres=%d DPI\n", yres);
+  DBG (7, "sanei_lexmark_low_set_scan_regs: resolution=%d DPI\n", resolution);
 
   /* colour mode */
   if (strcmp (dev->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_COLOR) == 0)
@@ -2595,14 +2592,14 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
       break;
     }
 
-  low_set_scan_area (yres,
+  low_set_scan_area (resolution,
 		       dev->val[OPT_TL_X].w,
 		       dev->val[OPT_TL_Y].w,
 		       dev->val[OPT_BR_X].w,
 		       dev->val[OPT_BR_Y].w,
 		       offset,
 		       dev->model.motor_type == A920_MOTOR && isColourScan
-		       && (yres == 600), dev->shadow_regs, dev);
+		       && (resolution == 600), dev->shadow_regs, dev);
 
   /* may be we could use a sensor descriptor that would held the max horiz dpi */
   if (dev->val[OPT_RESOLUTION].w < 600)
@@ -2611,7 +2608,7 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
     dev->shadow_regs[0x7a] = 1;
 
   /* 75dpi x 75dpi */
-  if (yres == 75)
+  if (resolution == 75)
     {
       DBG (5, "sanei_lexmark_low_set_scan_regs(): 75 DPI resolution\n");
 
@@ -2885,7 +2882,7 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
     }
 
   /* 150dpi x 150dpi */
-  if (yres == 150)
+  if (resolution == 150)
     {
       DBG (5, "sanei_lexmark_low_set_scan_regs(): 150 DPI resolution\n");
 
@@ -3180,7 +3177,7 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
     }
 
   /*300dpi x 300dpi */
-  if (yres == 300)
+  if (resolution == 300)
     {
       DBG (5, "sanei_lexmark_low_set_scan_regs(): 300 DPI resolution\n");
 
@@ -3434,7 +3431,7 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
     }
 
   /* 600dpi x 600dpi */
-  if (yres == 600)
+  if (resolution == 600)
     {
       DBG (5, "sanei_lexmark_low_set_scan_regs(): 600 DPI resolution\n");
 
@@ -3723,7 +3720,7 @@ sanei_lexmark_low_set_scan_regs (Lexmark_Device * dev, SANE_Int offset,
       dev->shadow_regs[0x79] = 0x40;
     }
   /*600dpi x 1200dpi */
-  if (yres == 1200)
+  if (resolution == 1200)
     {
       DBG (5, "sanei_lexmark_low_set_scan_regs(): 1200 DPI resolution\n");