diff --git a/convert-scan-for-pyfai.py b/convert-scan-for-pyfai.py
index d53a47a..0418aac 100644
--- a/convert-scan-for-pyfai.py
+++ b/convert-scan-for-pyfai.py
@@ -1,13 +1,23 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+# author J.Beale
 
 """
 # aim
-make image file for input into pyFAI for initial detector 
+make image file to input into pyFAI for initial detector beam-centre and detector distance calibration
+refer to Cristallina8M-calibration for complete protocol
+https://docs.google.com/document/d/1RoeUUogvRxX4M6uqGwkjf3dVJBabiMUx4ZxwcA5e9Dc/edit#
 
 # protocol
 take scan of LaB6
-vanile settings for crystallina 8M are 100 scan positions, 10 shots per position
-run this on output
+## IMPORTANT ##
+- save image as photon-counts - in slic/run_control scale=beam energy
+- detector_geometry=TRUE - saves detector panels in their correct orientation
+## scan inputs ##
+- <0.01 trans
+- motor scan > 10 um per step
+- 10 images per step, 100 steps
+- use scan.json as input for this script
 
 # usage
 python make-tiff.py -j <jugfrau-name> -s <path to scan file> -n <name of output file>
@@ -52,7 +62,7 @@ if __name__ == "__main__":
     parser.add_argument(
         "-j",
         "--jungfrau",
-        help="name of the jungfrau used",
+        help="name of the jungfrau used, i.e., JF17T16V01 for Cristallina MX",
         type=str,
         default="JF17T16V01"
     )