Index: /trunk/ippconfig/recipes/ppSim.config
===================================================================
--- /trunk/ippconfig/recipes/ppSim.config	(revision 41331)
+++ /trunk/ippconfig/recipes/ppSim.config	(revision 41332)
@@ -122,4 +122,5 @@
 
 # filter-dependent parameters
+# NOTE: these are only used if ZEROPOINT is set to NAN
 ZEROPTS  METADATA
 	g	F32	24.00
Index: /trunk/ippconfig/simtest/ppSim.config
===================================================================
--- /trunk/ippconfig/simtest/ppSim.config	(revision 41331)
+++ /trunk/ippconfig/simtest/ppSim.config	(revision 41332)
@@ -48,6 +48,7 @@
  SEEING      	 F32    1.0
  SCALE       	 F32    0.25
- ZEROPOINT   	 F32    25.0
- SKY.MAGS    	 F32    22.0
+ ZEROPOINT   	 F32    25.0            # if this value is not NAN, it overrides the per-filter zero points
+ 		 			# set in the ZEROPTS metadata (see recipes/ppSim.config)
+ SKY.MAGS    	 F32    22.0		# if SKY.RATE is set (not NAN), it overrides this value
 END