Index: trunk/ppSim/src/ppSimMakeSky.c
===================================================================
--- trunk/ppSim/src/ppSimMakeSky.c	(revision 16497)
+++ trunk/ppSim/src/ppSimMakeSky.c	(revision 17557)
@@ -13,15 +13,16 @@
     pmFPA  *fpa  = chip->parent;
 
-    float expTime     = psMetadataLookupF32(&status, config->arguments, "EXPTIME"); // Exposure time
-    float flatSigma   = psMetadataLookupF32(&status, config->arguments, "FLAT.SIGMA"); // Flat-field coefficient
-    float flatRate    = psMetadataLookupF32(&status, config->arguments, "FLAT.RATE"); // Flat-field rate
-    float shutterTime = psMetadataLookupF32(&status, config->arguments, "SHUTTER.TIME"); // Shutter time
+    psMetadata *recipe = psMetadataLookupMetadata(&status, config->recipes, PPSIM_RECIPE); // Recipe
 
-    float skyRate     = psMetadataLookupF32(&status, config->arguments, "SKY.RATE"); // Sky rate
+    float expTime     = psMetadataLookupF32(&status, recipe, "EXPTIME"); // Exposure time
+    float flatSigma   = psMetadataLookupF32(&status, recipe, "FLAT.SIGMA"); // Flat-field coefficient
+    float flatRate    = psMetadataLookupF32(&status, recipe, "FLAT.RATE"); // Flat-field rate
+    float shutterTime = psMetadataLookupF32(&status, recipe, "SHUTTER.TIME"); // Shutter time
+    float skyRate     = psMetadataLookupF32(&status, recipe, "SKY.RATE"); // Sky rate
     if (isnan(skyRate)) {
-	float zp      = psMetadataLookupF32(&status, config->arguments, "ZEROPOINT"); assert (status);
-	float scale   = psMetadataLookupF32(&status, config->arguments, "SCALE");     assert (status);
-	float skyMags = psMetadataLookupF32(&status, config->arguments, "SKY.MAGS");  assert (status);
-	skyRate = scale * scale * pow (10.0, -0.4*(skyMags - zp));
+	float zp      = psMetadataLookupF32(&status, recipe, "ZEROPOINT"); assert (status);
+	float scale   = psMetadataLookupF32(&status, recipe, "SCALE");     assert (status);
+	float skyMags = psMetadataLookupF32(&status, recipe, "SKY.MAGS");  assert (status);
+	skyRate = scale * scale * ppSimMagToFlux (skyMags, zp);
     }