diff --git a/src/main/java/bigtrace/BigTraceData.java b/src/main/java/bigtrace/BigTraceData.java
index a863a8d..7b3938b 100644
--- a/src/main/java/bigtrace/BigTraceData.java
+++ b/src/main/java/bigtrace/BigTraceData.java
@@ -3,7 +3,6 @@
 import java.awt.Color;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.concurrent.atomic.AtomicInteger;
 
 import bigtrace.gui.BCsettings;
 import bigtrace.gui.RenderSettings;
diff --git a/src/main/java/bigtrace/volume/ExtractROIBox.java b/src/main/java/bigtrace/volume/ExtractROIBox.java
index 1b0d2bd..9d8543e 100644
--- a/src/main/java/bigtrace/volume/ExtractROIBox.java
+++ b/src/main/java/bigtrace/volume/ExtractROIBox.java
@@ -78,9 +78,9 @@ protected Void doInBackground() throws Exception {
 		//output calibration
 		cal.setUnit(bt.btData.sVoxelUnit);
 		cal.setTimeUnit(bt.btData.sTimeUnit);
-		cal.pixelWidth = BigTraceData.dMinVoxelSize;
-		cal.pixelHeight= BigTraceData.dMinVoxelSize;
-		cal.pixelDepth = BigTraceData.dMinVoxelSize;
+		cal.pixelWidth = BigTraceData.globCal[0];
+		cal.pixelHeight= BigTraceData.globCal[1];
+		cal.pixelDepth = BigTraceData.globCal[2];
 		final int nTotROIs = listROIs.size();  
 		if(nTotROIs == 0)
 			return null;