--- ray/doc/man/man1/rcontrib.1	2016/09/12 20:31:34	1.13
+++ ray/doc/man/man1/rcontrib.1	2018/01/26 18:31:23	1.15
@@ -1,4 +1,4 @@
-.\" RCSid "$Id: rcontrib.1,v 1.13 2016/09/12 20:31:34 greg Exp $"
+.\" RCSid "$Id: rcontrib.1,v 1.15 2018/01/26 18:31:23 rschregle Exp $"
 .TH RCONTRIB 1 5/25/05 RADIANCE
 .SH NAME
 rcontrib - compute contribution coefficients in a RADIANCE scene
@@ -283,12 +283,13 @@ A command argument beginning with an at sign ('@') is 
 replaced by the contents of the given file.
 .PP
 .I Rcontrib
-has EXPERIMENTAL support for light source contributions from photon maps
-generated by
+supports light source contributions from photon maps generated by
 .I mkpmap(1)
 with its
 .I -apC
-option. In photon mapping mode,
+option. Enabling photon mapping is described in the
+.I rtrace 
+man page along with its relevant settings. In photon mapping mode,
 .I rcontrib
 only supports contributions from light sources, not arbitrary modifiers.
 The
@@ -298,7 +299,7 @@ discussed above. Ray coefficients are also supported v
 .I \-V-
 option. Using fewer photons than there are light sources for the photon
 density estimates results in omitted contributions, thus the bandwidth
-is clamped accordingly and a warning issued.
+is clamped accordingly and a warning is issued. 
 .SH EXAMPLES
 To compute the proportional contributions from sources modified
 by "light1" vs. "light2" on a set of illuminance values: