diff --git a/CHANGELOG.md b/CHANGELOG.md
index 533955e..28ce529 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 - Added GPX parser
+- Added optional dry-run modifier
 
 ## [0.2] - 2020-02-05
 ### Added
diff --git a/exif_rad.py b/exif_rad.py
index 9f661c6..e9c068f 100755
--- a/exif_rad.py
+++ b/exif_rad.py
@@ -30,6 +30,8 @@ parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFo
     them into the Exif tags of given photos.''')
 parser.add_argument('-si', '--sifactor', type=float, default=0.0065, 
                     help='Factor to multiply recorded CPM with.')
+parser.add_argument('-d', '--dry', action='store_true', 
+                    help='Dry-run, do not actually write anything.')
 parser.add_argument('csv', metavar='CSV', type=str, 
                     help='Geiger counter history file in CSV format.')
 parser.add_argument('-g', '--gpx', metavar='GPX', type=str,
@@ -60,8 +62,13 @@ for srcphoto in args.photos:
     else:
         # be os aware and use the correct directory delimiter for destfile
         dstphoto = os.path.join(args.outdir, photo_basename)
-        shutil.copy(srcphoto, dstphoto)
-        photo = dstphoto
+        print('dry-run:', args.dry)
+        if args.dry == 'True':
+            print('Copying file!')
+            shutil.copy(srcphoto, dstphoto)
+            photo = dstphoto
+        else:
+            photo = srcphoto
 
     # Load Exif data from image
     metadata = pyexiv2.ImageMetadata(photo)
@@ -89,7 +96,8 @@ for srcphoto in args.photos:
                 # print found radiation levels
                 print('{:<15} {:<20} {:<22}'.format(photo_basename, str(pictime), new_comment))
                 # Write Exif tags to file
-                metadata.write()
+                if args.dry == 'True':
+                    metadata.write()
                 break
         else:
             print('{:<15} {:<20} {:<22}'.format(photo_basename, str(pictime), 'NOT FOUND!'))
@@ -97,7 +105,7 @@ for srcphoto in args.photos:
     f.close()
 
     # Import GPX track(s)
-    if hasattr(args, 'gpx'):
+    if args.gpx is not None:
         gpx_file = open(args.gpx, 'r')
         gpxreader = gpxpy.parse(gpx_file)