Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/include/relphot.h
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/include/relphot.h	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/include/relphot.h	(revision 33807)
@@ -198,5 +198,5 @@
 int           args                PROTO((int argc, char **argv));
 int           args_client         PROTO((int argc, char **argv));
-int           bcatalog            PROTO((Catalog *subcatalog, Catalog *catalog));
+int           bcatalog            PROTO((Catalog *subcatalog, Catalog *catalog, int Ncat));
 void          clean_images        PROTO((void));
 void          clean_measures      PROTO((Catalog *catalog, int Ncatalog, int final, FlatCorrectionTable *flatcorr));
Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/StarOps.c
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/StarOps.c	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/StarOps.c	(revision 33807)
@@ -178,5 +178,9 @@
 
 	if (getImageEntry (m, Nc) < 0) {
-	  Mcal = Mmos = Mgrid = 0;
+	  // measurements without an image are either external reference photometry or
+	  // data for which the associated image has not been loaded (probably because of
+	  // overlaps).  Msys + measure.Mcal is our best guess of the true magnitude
+	  Mmos = Mgrid = 0;
+	  Mcal = catalog[Nc].measureT[m].Mcal; // check that this is zero for loaded REF value
 	} else {
 	  Mcal  = getMcal  (m, Nc, flatcorr, catalog);
@@ -429,4 +433,5 @@
 
 	  if (getImageEntry (m, i) < 0) {
+	  XXXX : likely problem -- compare with setMrel_catalog;
 	    // these detetions have no image (eg, ref values such as 2MASS)
 	    Mcal = Mmos = Mgrid = 0;
@@ -795,4 +800,7 @@
 	if (isnan(Mgrid)) continue;
 
+	// note that measurements for which the image is not selected will not up modified
+	// (that is a good thing! -- we keep a prior calibration)
+
 	// set the output calibration
 	catalog[i].measure[m].Mcal = Mcal + Mmos + Mgrid;
Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/bcatalog.c
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/bcatalog.c	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/bcatalog.c	(revision 33807)
@@ -3,5 +3,5 @@
 int LimitDensityCatalog_ByNmeasure (Catalog *subcatalog, Catalog *oldcatalog);
 
-int bcatalog (Catalog *subcatalog, Catalog *catalog) {
+int bcatalog (Catalog *subcatalog, Catalog *catalog, int Ncat) {
   
   off_t i, j, offset;
@@ -159,7 +159,15 @@
       subcatalog[0].measureT[Nmeasure].averef = Naverage;
       if (RESET) { 
-	if (!KEEP_UBERCAL) {
-	  subcatalog[0].measureT[Nmeasure].Mcal = 0;
-	  subcatalog[0].measureT[Nmeasure].dbFlags &= ~ID_MEAS_PHOTOM_UBERCAL;
+	// only reset Mcal for measures with a matching image
+	// do not reset Mcal for ubercal images unless explicitly requested
+	if (subcatalog[0].measureT[Nmeasure].dbFlags & ID_MEAS_PHOTOM_UBERCAL) {
+	  if (!KEEP_UBERCAL) {
+	    subcatalog[0].measureT[Nmeasure].Mcal = 0.0;
+	    subcatalog[0].measureT[Nmeasure].dbFlags &= ~ID_MEAS_PHOTOM_UBERCAL;
+	  } 
+	} else {
+	  if (getImageEntry (Nmeasure, Ncat) >= 0) {
+	    subcatalog[0].measureT[Nmeasure].Mcal = 0.0;
+	  }
 	}
 	subcatalog[0].measureT[Nmeasure].dbFlags &= ~PHOTOM_FLAGS;
Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/load_catalogs.c
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/load_catalogs.c	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/load_catalogs.c	(revision 33807)
@@ -68,5 +68,5 @@
 
     // select only the brighter stars
-    bcatalog (&catalog[i], &tcatalog);
+    bcatalog (&catalog[i], &tcatalog, i);
     dvo_catalog_unlock (&tcatalog);
     dvo_catalog_free (&tcatalog);
Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/select_images.c
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/select_images.c	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/select_images.c	(revision 33807)
@@ -122,12 +122,44 @@
     RmaxSkyRegion = RmaxSkyRegionAlt;
   }
-  
   double RmidSkyRegion = 0.5*(RminSkyRegion + RmaxSkyRegion);
   MARKTIME("create sky region coords: %f sec\n", dtime);
 
-  // if we overlap 0,360, RminSkyRegion will be 180 (or so)
-
   dsortindex (RmaxSky, index, skylist[0].Nregions);
   MARKTIME("sort sky coords: %f sec\n", dtime);
+
+  // generate a set of Rmin/Rmax values using this RmidSkyRegion for DEC bands of width
+  // dDecBand (0.1 deg).  DecIndex = (Dec + 90) / dDecBand
+  double *RminBand, *RmaxBand;
+  float dDecBand = 0.1;
+  int NDecBands = 180 / dDecBand + 1;
+  ALLOCATE (RminBand, double, NDecBands);
+  ALLOCATE (RmaxBand, double, NDecBands);
+  for (i = 0; i < NDecBands; i++) {
+    RminBand[i] = +360.0;
+    RmaxBand[i] = -360.0;
+  }
+  
+   /* compare with each region file */
+  for (i = 0; i < skylist[0].Nregions; i++) { 
+    int iDecBandMin = (skylist[0].regions[i][0].Dmin + 90.0) / dDecBand;
+    int iDecBandMax = (skylist[0].regions[i][0].Dmax + 90.0) / dDecBand;
+
+    double RminAlt = ohana_normalize_angle_to_midpoint (skylist[0].regions[i][0].Rmin, RmidSkyRegion);
+    double RmaxAlt = ohana_normalize_angle_to_midpoint (skylist[0].regions[i][0].Rmax, RmidSkyRegion);
+
+    for (j = iDecBandMin; j <= iDecBandMax; j++) {
+      RminBand[j] = MIN(RminBand[j], RminAlt);
+      RmaxBand[j] = MAX(RmaxBand[j], RmaxAlt);
+    }
+  }
+
+# if (0)
+  // XXX quick test
+  FILE *fout = fopen ("dec.bands.dat", "w");
+  for (i = 0; i < NDecBands; i++) {
+    fprintf (fout, "%d %f : %f - %f\n", (int) i, dDecBand * i - 90.0, RminBand[i], RmaxBand[i]);
+  }
+  fclose (fout);
+# endif
 
   if (VERBOSE) fprintf (stderr, "finding images\n");
@@ -209,4 +241,29 @@
     if (RminImage > RmaxSkyRegion) continue;
     if (RmaxImage < RminSkyRegion) continue;
+
+    // the above checks are only valid for the outermost region.  however, at a given
+    // declination, the range of RA is limited by the actual catalog boundaries
+    // check if this image is in range for the Dmax and Dmin locations
+
+    int iDecBandMin = (DminImage + 90.0) / dDecBand;
+    int iDecBandMax = (DmaxImage + 90.0) / dDecBand;
+
+    // the sky region RA is defined to be 0 - 360.0
+    if (RminImage > RmaxBand[iDecBandMin]) { 
+      fprintf (stderr, "skip image %s (%f,%f) on boundary\n", timage[i].name, 0.5*(RminImage + RmaxImage), 0.5*(DminImage + DmaxImage));
+      continue;
+    }
+    if (RminImage > RmaxBand[iDecBandMax]) {
+      fprintf (stderr, "skip image %s (%f,%f) on boundary\n", timage[i].name, 0.5*(RminImage + RmaxImage), 0.5*(DminImage + DmaxImage));
+      continue;
+    }
+    if (RmaxImage < RminBand[iDecBandMin]) {
+      fprintf (stderr, "skip image %s (%f,%f) on boundary\n", timage[i].name, 0.5*(RminImage + RmaxImage), 0.5*(DminImage + DmaxImage));
+      continue;
+    }
+    if (RmaxImage < RminBand[iDecBandMax]) {
+      fprintf (stderr, "skip image %s (%f,%f) on boundary\n", timage[i].name, 0.5*(RminImage + RmaxImage), 0.5*(DminImage + DmaxImage));
+      continue;
+    }
 
     // image overlaps region, keep it
Index: branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/setMrelFinal.c
===================================================================
--- branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/setMrelFinal.c	(revision 33799)
+++ branches/eam_branches/ipp-20120405/Ohana/src/relphot/src/setMrelFinal.c	(revision 33807)
@@ -66,7 +66,16 @@
 	  }
 	
-	  if (!KEEP_UBERCAL) {
-	    catalog[0].measure[m].Mcal = 0;
-	    catalog[0].measure[m].dbFlags &= ~ID_MEAS_PHOTOM_UBERCAL;
+	  // only reset Mcal for measures with a matching image
+	  // do not reset Mcal for ubercal images unless explicitly requested
+
+	  if (catalog[0].measure[m].dbFlags & ID_MEAS_PHOTOM_UBERCAL) {
+	    if (!KEEP_UBERCAL) {
+	      catalog[0].measure[m].Mcal = 0.0;
+	      catalog[0].measure[m].dbFlags &= ~ID_MEAS_PHOTOM_UBERCAL;
+	    } 
+	  } else {
+	    if (getImageEntry (m, 0) >= 0) {
+	      catalog[0].measure[m].Mcal = 0.0;
+	    }
 	  }
 	  catalog[0].measure[m].dbFlags &= ~PHOTOM_FLAGS;