diff --git a/dashboard.py b/dashboard.py
index b650c7e..840be2d 100644
--- a/dashboard.py
+++ b/dashboard.py
@@ -176,6 +176,7 @@ class TimeSeries(Widget):
                 x0 = tickmarks[-1]["x"]
                 d0 = datetime.datetime.fromtimestamp(t0)
 
+                log.debug("step_i = %s", step_i)
                 if steps[step_i] == "s":
                     d1 = datetime.datetime(d0.year, d0.month, d0.day, d0.hour, d0.minute, d0.second)
                     t1 = d1.timestamp()
@@ -287,6 +288,7 @@ class TimeSeries(Widget):
                         t1 = d1.timestamp()
                         x1 = t2x(t1)
                         if x0 - x1 < min_step:
+                            log.debug("t0 = %s, x0 = %s, t1 = %s, x1 = %s", t0, x0, t1, x1)
                             step_i += 1
                             continue
                 if x1 < 0:
@@ -383,7 +385,7 @@ class TimeSeries(Widget):
             log.debug("")
 
 
-        log.debug("in graph")
+        log.debug("in graph for %s", self.lts.id)
         data = self.lts.data
         n = len(data)
         t_last = data[-1][0]
@@ -391,6 +393,7 @@ class TimeSeries(Widget):
             return "(not enough data)"
         dt = (t_last - data[-5][0]) / 4
         k = math.log((t_last - data[0][0]) / dt / n + 1)
+        log.debug("times = [%s ... %s ... %s]", data[0][0], data[-5][0], data[-1][0])
 
         max_value = max([d[3] if len(d) >= 4 else d[1] for d in self.lts.data])
         max_value = max(max_value, 0.001) # ensure positive