Index: /trunk/MagicSoft/TDAS-Extractor/Calibration.tex
===================================================================
--- /trunk/MagicSoft/TDAS-Extractor/Calibration.tex	(revision 6630)
+++ /trunk/MagicSoft/TDAS-Extractor/Calibration.tex	(revision 6631)
@@ -804,6 +804,12 @@
 \begin{enumerate}
 \item The intrinsic arrival time spread of the photons on the PMT. This time spread 
-can be estimated roughly by the intrinsic width of the calibration pulses of about 2\,ns 
-for the faster UV pulses and 3--4\,ns for the green and blue pulses. It amounts to 
+can be estimated roughly by the intrinsic width $\delta t_{\mathrm{LED}}$ 
+of the calibration pulses of about 2\,ns 
+for the faster UV pulses and 3--4\,ns for the green and blue pulses. The resulting time
+resolution is given by:
+\begin{equation}
+\Delta t \approx \frac{\delta t_{\mathrm{LED}}}{\sqrt{Q/{\mathrm{phe}}}}
+\end{equation}
+
 
 For our