Index: trunk/Ohana/src/libdvo/include/dvodb.h
===================================================================
--- trunk/Ohana/src/libdvo/include/dvodb.h	(revision 36490)
+++ trunk/Ohana/src/libdvo/include/dvodb.h	(revision 36630)
@@ -23,31 +23,60 @@
 /* magnitude types */
 enum {MAG_NONE, 
-      MAG_INST, 
-      MAG_CAT, 
-      MAG_APER, 
-      MAG_APER_INST, 
-      MAG_KRON, 
-      MAG_KRON_INST, 
-      MAG_KRON_ERR, 
-      MAG_SYS, 
-      MAG_REL, 
-      MAG_CAL, 
+
+      // these magnitude types are from the measurement table (or derived therein)
+      // the following imply PSF magnitudes:
+      MAG_INST, // -2.5*log(DN) [ie, not DN/sec]
+      MAG_CAT,  // MAG_INST + 2.5*log(exptime) + C_lambda + K_lambda*(airmass - 1)
+      MAG_SYS,  // MAG_CAT + \sum_i A_i * (color_i - color_o) [color correction for measure photcode]
+      MAG_REL,  // MAG_SYS - Mcal [specific zero point for image]
+      MAG_CAL,  // MAG_REL + \sum_i A_i * (color_i - color_o) [color correction for average photcode]
+      MAG_ERR,  // error on PSF MAG
+
+      // the following imply APERTURE magnitudes:
+      MAG_APER_INST, // -2.5*log(DN) [ie, not DN/sec]
+      MAG_APER_CAT,  // MAG_APER_INST + 2.5*log(exptime) + C_lambda + K_lambda*(airmass - 1)
+      MAG_APER_SYS,  // MAG_APER_CAT + \sum_i A_i * (color_i - color_o) [color correction for measure photcode]
+      MAG_APER_REL,  // MAG_APER_SYS - Mcal [specific zero point for image]
+      MAG_APER_CAL,  // MAG_APER_REL + \sum_i A_i * (color_i - color_o) [color correction for average photcode]
+      MAG_APER_ERR,  // error on APER MAG (if known, else psf error)
+      MAG_APER,      // in mextract -> MAG_APER_REL, in avextract -> MAG_APER_AVE
+
+      // the following imply KRON magnitudes:
+      MAG_KRON_INST, // -2.5*log(DN) [ie, not DN/sec]
+      MAG_KRON_CAT,  // MAG_KRON_INST + 2.5*log(exptime) + C_lambda + K_lambda*(airmass - 1)
+      MAG_KRON_SYS,  // MAG_KRON_CAT + \sum_i A_i * (color_i - color_o) [color correction for measure photcode]
+      MAG_KRON_REL,  // MAG_KRON_SYS - Mcal [specific zero point for image]
+      MAG_KRON_CAL,  // MAG_KRON_REL + \sum_i A_i * (color_i - color_o) [color correction for average photcode]
+      MAG_KRON_ERR,  // error on KRON MAG
+      MAG_KRON,      // in mextract -> MAG_KRON_REL, in avextract -> MAG_KRON_AVE
+
+      // these magnitude types are from the average (secfilt) table:
+      // the following imply PSF magnitudes (or fluxes)
       MAG_AVE, 
       MAG_REF, 
-      MAG_ERR, 
       MAG_STDEV, 
       MAG_AVE_ERR, 
+      MAG_CHISQ,
+      MAG_20, 
+      MAG_80, 
+      MAG_FLUX_PSF,
+      MAG_FLUX_PSF_ERR,
+
+      // the following imply APERTURE magnitudes:
+      MAG_APER_AVE,
+      MAG_APER_REF,
+
+      // the following imply KRON magnitudes or fluxes:
+      MAG_KRON_AVE,
+      MAG_KRON_REF,
+      MAG_FLUX_KRON,
+      MAG_FLUX_KRON_ERR,
+
+      // other secfilt fields of interest
       MAG_PHOT_FLAGS, 
-      MAG_CHISQ,
       MAG_NCODE,
       MAG_NPHOT,
-      MAG_20, 
-      MAG_80, 
       MAG_UC_DIST, 
       MAG_STACK_DET_ID, 
-      MAG_FLUX_PSF,
-      MAG_FLUX_PSF_ERR,
-      MAG_FLUX_KRON,
-      MAG_FLUX_KRON_ERR,
 };