Index: branches/eam_branches/relphot.20210521/src/ZeroPointModes.c
===================================================================
--- branches/eam_branches/relphot.20210521/src/ZeroPointModes.c	(revision 41602)
+++ branches/eam_branches/relphot.20210521/src/ZeroPointModes.c	(revision 41603)
@@ -49,5 +49,5 @@
       clean_mosaics(); // do this on every pass 
     }
-    if ((CurrentLoop >= 18) && (CurrentLoop <= 999)) {
+    if ((CurrentLoop >= 18) && (CurrentLoop < 21)) {
       // after iterating a few times on the TGroup & Mosaic zero points:
       // * identify the good / bad Mosaics
@@ -60,4 +60,16 @@
       clean_images(); // do this on every pass 
     }
+    if ((CurrentLoop >= 21) && (CurrentLoop <= 999)) {
+      // after iterating a few times on the TGroup & Mosaic zero points:
+      // * identify the good / bad Mosaics
+      // * fit the chips from the bad Mosaics
+      TGROUP_ZPT_MODE = TGROUP_ZPT_MODE_GOOD_NIGHT; // stop fitting the bad nights
+      MOSAIC_ZPT_MODE = MOSAIC_ZPT_MODE_BAD_NIGHT_GOOD_MOSAIC; // only fit good mosaics on bad nights
+      IMAGE_ZPT_MODE  = IMAGE_ZPT_MODE_BAD_NIGHT_BAD_MOSAIC; // only fit bad mosaics on bad nights
+      GRID_ZPT_MODE  = GRID_ZPT_MODE_ALL; // only fit bad mosaics on bad nights
+      clean_tgroups(); // do this on every pass 
+      clean_mosaics(); // do this on every pass 
+      clean_images(); // do this on every pass 
+    }
   }
 
@@ -68,5 +80,5 @@
       MOSAIC_ZPT_MODE = MOSAIC_ZPT_MODE_NONE;
     }
-    if ((CurrentLoop > 4) && (CurrentLoop <= 999)) {
+    if ((CurrentLoop > 4) && (CurrentLoop <= 8)) {
       // after iterating a few times on the TGroup zero points:
       // * identify the photometric nights
@@ -75,4 +87,14 @@
       MOSAIC_ZPT_MODE = MOSAIC_ZPT_MODE_NONE;
       IMAGE_ZPT_MODE  = IMAGE_ZPT_MODE_BAD_NIGHT;
+      clean_tgroups(); // do this on every pass or just sometimes?
+    }
+    if ((CurrentLoop > 8) && (CurrentLoop <= 999)) {
+      // after iterating a few times on the TGroup zero points:
+      // * identify the photometric nights
+      // * fit the images from the non-photometric nights
+      TGROUP_ZPT_MODE = TGROUP_ZPT_MODE_GOOD_NIGHT; // stop fitting the bad nights
+      MOSAIC_ZPT_MODE = MOSAIC_ZPT_MODE_NONE;
+      IMAGE_ZPT_MODE  = IMAGE_ZPT_MODE_BAD_NIGHT;
+      GRID_ZPT_MODE  = GRID_ZPT_MODE_ALL; // only fit bad mosaics on bad nights
       clean_tgroups(); // do this on every pass or just sometimes?
     }