diff --git a/Readme.md b/Readme.md
index a9d4248..f3d9981 100644
--- a/Readme.md
+++ b/Readme.md
@@ -4,21 +4,22 @@ exif_rad.py is a simple unix-style cross-platform Python 3 tool which can write
 
 It can scan a couple of images, extract their Exif-tags, and compare the `DateTimeOriginal` with other sources.
 
-By now it can parse a .his (CSV) file from a [GeigerLog](https://sourceforge.net/projects/geigerlog/) file export and calculate the radiation in µS/h using the factor in `SIFACTOR`.
+By now it can parse a .his (CSV) file from a [GeigerLog](https://sourceforge.net/projects/Geigerlog/) file export and calculate the radiation in µS/h using the factor in `SIFACTOR`.
 
 It then creates a `UserComment` Exif tag with the actual measured radiation at the time the photo has been taken.
 
 ## Dependencies
-Right now it depends on the following Python 3 libraries:
+Right now it depends on the following non-core Python 3 libraries:
 
   * [piexif](https://pypi.org/project/pyexif/): Python module for working with EXIF image data.
 
 ## Requirements
-  * GeigerCounter log file in csv format as it is being exported by the software GeigerLog. Such files look like this: `149654, 2020-02-27 05:12:42,    13.0,     0.0`
+  * GeigerCounter log file in csv format as it is being exported by the software GeigerLog. Such files look like this:
+  `# ID  , time in isoformat  ,    CP/M,    CP/S`
+  `149654, 2020-02-27 05:12:42,    13.0,     0.0`
   * A bunch of images (jpg, cr2, etc.) with its time of creation stored in `DateTimeOriginal`
-  * A gpx track
 
-All sources are matched by their timestamp, so all sources have to be recorded during the same time (and timezone)
+All sources are matched by their timestamp, so all sources have to be recorded during the same time (and timezone). The Geiger counter has to log a value every second, as the script compares the timestamps exactly.
 
 ## Usage
 
@@ -40,9 +41,40 @@ optional arguments:
                         Directory to output processed photos (default: .)
 ```
 
+## GeigerLog setup
+
+The Software is Open-Source and can be downloaded from [Sourceforge](https://sourceforge.net/projects/Geigerlog/).
+
+### Configure GeigerLog to use the GMC-Geiger counter
+
+The GMC device has to be enabled in the `geigerlog.cfg` which is located in the main program directory. Because GS (GammaScout) is preactivated, it can be disabled, while you want to enable GMC
+
+```-#GSActivation = no
+-GSActivation = yes
++GSActivation = no
++#GSActivation = yes
+```
+
+The GMC* defaults are quite sane, but you might want to set the correct serial port:
+
+`usbport   = /dev/ttyUSB0`
+
+### Using GeigerLog to download history
+
+Now the program can be started by double-clicking `geigerlog` or by executing `./geigerlog` on the command prompt.
+Once connected to the device (in any power state) by pressing 'Ctrl+C' , you can download the history ('History' -> 'GMC Series' -> 'Get History from Device'). You will be asked to choose a filename for the hisdb-file (SQLITE format).
+
+GeigerLog now presents you a rendering of the radiation over time in its main window:
+
+![alt text][main_window]
+
+[main_window]: images/geigerlog_main_window.png "GeigerLog Main Window with graph"
+
+Once imported, you can export the history into a hisdb.his-file, which is basically the CSV-file `exif_rad.py` can process. Choose 'History' -> Save History Data into .his file (CSV)'.
+
 
 ## future possibilities
 
   * In the future it should also be able to do the same with a gpx-file to extract geolocations and to write them into the appropiate Exif-fields.
   * It might get a setup.py if I want to waste my time on it.
-  * I might want to get rid of the requirement to use a bloated GUI application to download the history data off the geigercounter. There must be a neat working command line tool. Maybe I'll write it myswlf.
+  * I might want to get rid of the requirement to use a bloated GUI application to download the history data off the Geigercounter. There must be a neat working command line tool. Maybe I'll write it myself.
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