diff --git a/figures/clocks/reference-clock.pdf b/figures/clocks/reference-clock.pdf
index 1016fd7..93bbe97 100644
Binary files a/figures/clocks/reference-clock.pdf and b/figures/clocks/reference-clock.pdf differ
diff --git a/figures/clocks/src/reference-clock.py b/figures/clocks/src/reference-clock.py
index 42b1d66..240a168 100755
--- a/figures/clocks/src/reference-clock.py
+++ b/figures/clocks/src/reference-clock.py
@@ -12,13 +12,18 @@ import scipy.signal as sig
 
 ### Functions
 
-def plot_signal( ax, t, t_edge, s_edge, name=None, box_kw={'hatch': '/'}, line_kw={}, annotate_t_edge=True,**plot_kw):
+def plot_signal( ax, t, t_edge, s_edge, name=None, box_kw={'hatch': '/'}, line_kw={}, annotate_t_edge=True, divide_s_edge=False,**plot_kw):
     """
     Plot a signal directly on an axis.
     Uses t_edge to trigger height
     """
-    lower = (t > t_edge)
-    upper = (t > t_edge + s_edge)
+    if divide_s_edge:
+        lower = (t > t_edge - s_edge/2)
+        upper = (t > t_edge + s_edge/2)
+    else:
+        lower = (t > t_edge)
+        upper = (t > t_edge + s_edge)
+
 
     # merge dictionaries correctly
     line_kw = { **plot_kw, **line_kw }
@@ -35,7 +40,6 @@ def plot_signal( ax, t, t_edge, s_edge, name=None, box_kw={'hatch': '/'}, line_k
     l2 = ax.plot(t, upper, **line_kw)
 
     # plot the shaded box of width t_sigma
-
     l3 = ax.fill_between(t, upper, lower, **box_kw)
 
     # annotations
@@ -45,12 +49,15 @@ def plot_signal( ax, t, t_edge, s_edge, name=None, box_kw={'hatch': '/'}, line_k
             y = 1
             ax.annotate("$t_\mathrm{{{}}}$".format(name),
                     xy=(t_edge, y), xytext=(t_edge-3, y),
-                    va='top', ha='center'
+                    va='bottom', ha='center'
             )
 
         # annotate s_edge
         y = 0.3
-        annotate_width(ax, "$\sigma_\mathrm{{{}}}$".format(name), t_edge, t_edge+s_edge, y)
+        if divide_s_edge:
+            annotate_width(ax, "$\sigma_\mathrm{{{}}}$".format(name), t_edge-s_edge/2, t_edge+s_edge/2, y)
+        else:
+            annotate_width(ax, "$\sigma_\mathrm{{{}}}$".format(name), t_edge, t_edge+s_edge, y)
 
     return [l, l2, l3]
 
@@ -88,7 +95,7 @@ def annotate_width(ax, name, x1, x2, y, text_kw={}, arrow_kw={}):
 
 
 ## Main
-def main():
+def main(ref=(10,5), A=(40,10), B=(70,12) ):
     """
     Create a figure with two signals at times t1 and t2 (accuracy s1, s2)
     as compared to a reference timer tr (sr), with annotations.
@@ -96,24 +103,21 @@ def main():
     
     t = np.linspace(0, 100, 1e3)
 
-    t_A = 40
-    t_B = 70
-    t_ref = 10
-
-    s_A = 10
-    s_B = 10
-    s_ref = 5
+    t_A, s_A = A
+    t_B, s_B = B
+    t_ref, s_ref = ref
    
     box_kw = {
-            "alpha": 0.3,
+            "alpha": 0.6,
             "hatch": '\\',
     }
     line_kw = {
             }
 
     vline_kw = {
-            "linestyle": '--',
+            "linestyle": (0,(4,2)),
             "color": "k",
+            "alpha":0.8,
             }
  
     fig, axs = plt.subplots(3,1,sharex=True, gridspec_kw={'hspace': 0});
@@ -122,10 +126,14 @@ def main():
     axs[-1].set_xticks([])
     axs[-1].set_xticklabels([])
     for ax in axs:
-        ax.set_ylim(-0.2, 1.2)
+        ax.set_ylim(-0.25, 1.25)
         ax.set_yticks([])
         ax.set_yticklabels([])
         ax.grid()
+        ax.spines['top'].set_visible(False)
+        ax.spines['right'].set_visible(False)
+        ax.spines['bottom'].set_visible(False)
+        ax.spines['left'].set_visible(False)
 
     # Create the plots
     i = -1
@@ -133,20 +141,20 @@ def main():
     # Signal A
     i+=1
     y = 0.6
-    axs[i].set_ylabel("Signal A")
+    axs[i].set_ylabel("Signal A", rotation=0)
     plot_diff_time(axs[i], "$t_\\mathrm{A}}$", t_ref, t_A, y, vline_kw=vline_kw)
     plot_signal(axs[i], t, t_A, s_A, name="A", box_kw=box_kw, line_kw=line_kw, annotate_t_edge=False)
 
     # Reference
     i+=1
-    axs[i].set_ylabel("Reference")
+    axs[i].set_ylabel("Reference", rotation=0)
     axs[i].axvline(t_ref, **vline_kw)
     plot_signal(axs[i], t, t_ref, s_ref, name="ref", box_kw=box_kw, line_kw=line_kw, color='g')
     plot_diff_time(axs[i], "$t_\\mathrm{C}$", t_A, t_B, 0.3, vline_kw=vline_kw)
 
     # Signal B
     i+=1
-    axs[i].set_ylabel("Signal B")
+    axs[i].set_ylabel("Signal B", rotation=0)
     plot_diff_time(axs[i], "$t_\\mathrm{B}}$", t_ref, t_B, y, vline_kw=vline_kw)
     plot_signal(axs[i], t, t_B, s_B, name="B", box_kw=box_kw, line_kw=line_kw, color='purple', annotate_t_edge=False)
 
@@ -170,7 +178,8 @@ if __name__ == "__main__":
     fig, _ = main()
 
     if args.fname is not None:
-        plt.savefig(args.fname)
+        plt.tight_layout()
+        plt.savefig(args.fname, transparent=True)
     else:
         plt.show()
 
diff --git a/presentations/2022-12-15_group_meeting/Makefile b/presentations/2022-12-15_group_meeting/Makefile
new file mode 100644
index 0000000..449c34a
--- /dev/null
+++ b/presentations/2022-12-15_group_meeting/Makefile
@@ -0,0 +1,24 @@
+# vim:ft=make
+-include config.mk
+
+.PHONY: all clean dist-clean
+
+### Variables
+MAIN_SRC  ?= main.tex
+TEXENGINE ?= latexmk --pdf
+
+MAIN_TARGET = $(patsubst %.tex,%.pdf,$(MAIN_SRC))
+
+### Targets
+all: $(MAIN_TARGET)
+
+dist: all clean
+
+$(MAIN_TARGET): $(MAIN_SRC)
+	$(TEXENGINE) $^
+
+dist-clean: clean
+	@rm -vf *.pdf *.eps *.dvi *.ps
+
+clean:
+	@rm -vf *.dat *.log *.out *.aux *.nav *.snm *.toc *.vrb *~ *.fls *.fdb_latexmk *-blx.bib *.bbl *.blg *.run.xml
diff --git a/presentations/2022-12-15_group_meeting/config.mk b/presentations/2022-12-15_group_meeting/config.mk
new file mode 100644
index 0000000..fb559e2
--- /dev/null
+++ b/presentations/2022-12-15_group_meeting/config.mk
@@ -0,0 +1 @@
+MAIN_SRC=2022-12-15_CRHEP.tex