diff --git a/eodb/events/management/commands/activity.py b/eodb/events/management/commands/activity.py
index 45af984..acf83fd 100644
--- a/eodb/events/management/commands/activity.py
+++ b/eodb/events/management/commands/activity.py
@@ -20,16 +20,12 @@ class Command(GraphCommand):
     def handle(self, *args, **options):
         title = 'Git activity'
 
-        datetime_var = 'author_datetime'
-        if options.get('committime'):
-            datetime_var = 'commit_datetime'
-
         total_events = {}
         plots = []
         for i, (legend, serie) in enumerate(self.get_series(options)):
             events = {}
             for commit in serie:
-                commit_date = getattr(commit, datetime_var).date()
+                commit_date = self.get_event_datetime(commit, options).date()
                 if options.get('groupby') == 'weeks':
                     graph_date = commit_date - datetime.timedelta(days=commit_date.weekday())
                 elif options.get('groupby') == 'months':
diff --git a/eodb/events/management/commands/common.py b/eodb/events/management/commands/common.py
index a5474d3..287bf2d 100644
--- a/eodb/events/management/commands/common.py
+++ b/eodb/events/management/commands/common.py
@@ -5,6 +5,7 @@ import matplotlib.pyplot as plt
 from django.core.management.base import BaseCommand, CommandError
 from django.db.models import Q
 from django.utils.dateparse import parse_date
+from django.utils.timezone import make_aware, make_naive
 
 from eodb.events.models import Commit, Email, Redmine, Formdata
 
@@ -19,6 +20,8 @@ class GraphCommand(BaseCommand):
         parser.add_argument('--events', default='git',
                 help='use event of this type (git (default), emails, redmine)')
         parser.add_argument('--notitle', action='store_true')
+        parser.add_argument('--entrouvert', action='store_true',
+                help='limit to @entrouvert persons')
         parser.add_argument('--filename', metavar='FILENAME')
 
     def get_series(self, options):
@@ -39,14 +42,22 @@ class GraphCommand(BaseCommand):
         else:
             yield (None, self.get_events(options))
 
+    def get_event_datetime(self, event, options):
+        datetime_var = 'author_datetime'
+        if options.get('committime'):
+            datetime_var = 'commit_datetime'
+        return make_aware(make_naive(getattr(event, datetime_var)))
+
     def get_events(self, options):
-        if options['events'] in ('formdata',):
-            domain_filter = Q(author_datetime__isnull=False)
-        else:
+        if options.get('entrouvert'):
             domain_filter = Q(author_email__endswith='@entrouvert.com') | \
                             Q(author_email__endswith='@entrouvert.org')
-        filters = {}
+        elif options['events'] in ('formdata',):
+            domain_filter = Q(author_datetime__isnull=False)
+        else:
+            domain_filter = Q()
 
+        filters = {}
         if options.get('username'):
             filters['author_email__startswith'] = options['username'] + '@'
 
diff --git a/eodb/events/management/commands/punchcard.py b/eodb/events/management/commands/punchcard.py
index 3f29d0b..b1d4af2 100644
--- a/eodb/events/management/commands/punchcard.py
+++ b/eodb/events/management/commands/punchcard.py
@@ -12,10 +12,6 @@ class Command(GraphCommand):
             for j in range(24):
                 infos[(i, j)] = 0
 
-        datetime_var = 'author_datetime'
-        if options.get('committime'):
-            datetime_var = 'commit_datetime'
-
         def hour_shift(x):
             x = x - 4
             if x < 0:
@@ -23,7 +19,9 @@ class Command(GraphCommand):
             return x
 
         for commit in self.get_events(options):
-            coords = (getattr(commit, datetime_var).weekday(), hour_shift(getattr(commit, datetime_var).hour))
+            coords = (
+                    self.get_event_datetime(commit, options).weekday(),
+                    hour_shift(self.get_event_datetime(commit, options)).hour))
             infos[coords] = infos[coords] + 1
 
         draw_punchcard(infos,
diff --git a/eodb/events/management/commands/times.py b/eodb/events/management/commands/times.py
index 081ff2e..c9127d1 100644
--- a/eodb/events/management/commands/times.py
+++ b/eodb/events/management/commands/times.py
@@ -17,16 +17,12 @@ class Command(GraphCommand):
         parser.add_argument('--density', action='store_true')
 
     def handle(self, *args, **options):
-        datetime_var = 'author_datetime'
-        if options.get('committime'):
-            datetime_var = 'commit_datetime'
-
         event_dates = []
         event_times = []
         plots = []
         for i, (legend, serie) in enumerate(self.get_series(options)):
             for commit in serie:
-                graph_date = getattr(commit, datetime_var)
+                graph_date = self.get_event_datetime(commit, options)
                 graph_date -= datetime.timedelta(hours=4)
                 event_dates.append(matplotlib.dates.date2num(graph_date.date()))
                 event_times.append(graph_date.hour + graph_date.minute / 60. + graph_date.second / 3600)
diff --git a/eodb/events/management/commands/violins.py b/eodb/events/management/commands/violins.py
index dd80e53..4357d7f 100644
--- a/eodb/events/management/commands/violins.py
+++ b/eodb/events/management/commands/violins.py
@@ -14,10 +14,6 @@ np.random.seed(19680801)
 class Command(GraphCommand):
 
     def handle(self, *args, **options):
-        datetime_var = 'author_datetime'
-        if options.get('committime'):
-            datetime_var = 'commit_datetime'
-
         data = []
         zones = []
         for i, (legend, serie) in enumerate(self.get_series(options)):
@@ -25,7 +21,7 @@ class Command(GraphCommand):
             events = []
             data.append(events)
             for event in serie:
-                event_date = getattr(event, datetime_var)
+                event_date = self.get_event_datetime(event, options)
                 hour = event_date.hour
                 if hour < 5:
                     hour += 24