bring doc page up to date, re #12610

Code/Mantid/docs/source/interfaces/Engineering_Diffraction.rst

@@ -7,36 +7,97 @@ Engineering Diffraction
 Overview
 --------
 
-This custom interface integrates several taks related to engineeering
-diffraction. This is under heavy development, at the moment the
-interface only provides calibration related functionality. The
+This custom interface integrates several tasks related to engineeering
+diffraction. The interface is under heavy development, and at the
+moment it only provides calibration related functionality. The
 following sections will describe the different sections or tabs of the
 interface.
 
 .. interface:: Engineering Diffraction
   :align: center
   :width: 400
 
+General options
+^^^^^^^^^^^^^^^
+Instrument
+ Select the instrument. Only ENGIN-X (ISIS) is supported in this version.
+
+?
+  Shows this documentation page.
+
+Close
+  Close the interface
+
 Calibration
 -----------
 
 This tab provides a graphical interface to calculate calibrations and
 visualize them.
 
-.. interface:: Engineering Diffraction
-  :widget: wCalib
-  :align: right
-  :width: 300
+It is possible to load an existing calibration (as a CSV file) and to
+generate a new calibration file (which becomes the new current
+calibration).
+
+Parameters
+^^^^^^^^^^
+
+These parameters are required to generate new calibrations:
+
+Vanadium#
+  Number of the vanadium run used to correct calibration and experiment
+  runs.
+
+CeO2#
+  Number of the Ceria (short) run used to calibrate experiment runs.
 
 Settings
 --------
 
 Controls several settings, including the input folders where the
-intrument run files can be found.
+instrument run files can be found. Other advanced options can also be
+controlled to customize the way the underlying calculations are
+performed.
 
-.. interface:: Engineering Diffraction
-  :widget: wSettings
-  :align: right
-  :width: 300
+Calibration Parameters
+^^^^^^^^^^^^^^^^^^^^^^
+
+The calibration settings are organized in three blocks:
+1. Input directories
+2. Pixel calibration
+3. Advanced settings
+
+The input directories will be used when looking for run files
+(Vanadium and Ceria). They effectivel ybecome part of the search path
+of Mantid when using this interface.
+
+The pixel calibration file contains the calibration of every pixel of
+all banks, as produced by the algorithm :ref:`EnggCalibrateFull
+<algm-EnggCalibrateFull>`.
+
+The Following advanced settings are available to customize the
+behavior of this interface:
+
+Force recalculate
+  Vanadium corrections will be recalculated even if previous correction
+  results are available for the current Vanadium run number.
+
+Tempalte .prm file
+  Use a different template file for the output GSAS IPAR that is
+  generated in the Calibration tab.
+
+Rebin for Calibrate
+  This sets a rebin width parameter that can be used by underlying
+  algorithms such as :ref:`EnggCalibrate <algm-EnggCalibrate>` and
+  :ref:`EnggFocus <algm-EnggFocus>`
+
+Algorithms
+----------
+
+Most of the functionality provided by this interface is based on the
+engineering diffraction Mantid algorithms (which are named with the
+prefix *Engg*. This includes :ref:`EnggCalibrate
+<algm-EnggCalibrate>`, :ref:`EnggCalibrateFull
+<algm-EnggCalibrateFull>`, :ref:`Engg <algm-EnggCalibrateFull>`,
+explained in detail in the Mantid algorithm description.
 
 .. categories:: Interfaces Diffraction