--- ray/doc/man/man1/rpict.1	2008/11/10 19:08:17	1.13
+++ ray/doc/man/man1/rpict.1	2014/01/25 18:27:39	1.16
@@ -1,4 +1,4 @@
-.\" RCSid "$Id: rpict.1,v 1.13 2008/11/10 19:08:17 greg Exp $"
+.\" RCSid "$Id: rpict.1,v 1.16 2014/01/25 18:27:39 greg Exp $"
 .TH RPICT 1 2/26/99 RADIANCE
 .SH NAME
 rpict - generate a RADIANCE picture
@@ -335,13 +335,13 @@ This option may be desirable in conjunction with the
 .I \-i
 option so that light sources do not appear in the output.
 .TP
-.BI -sj \ frac
-Set the specular sampling jitter to
-.I frac.
-This is the degree to which the highlights are sampled
-for rough specular materials.
-A value of one means that all highlights will be fully sampled
-using distributed ray tracing.
+.BI -ss \ samp
+Set the specular sampling to
+.I samp.
+For values less than 1, this is the degree to which the highlights
+are sampled for rough specular materials.
+A value greater than one causes multiple ray samples to be sent
+to reduce noise at a commmesurate cost.
 A value of zero means that no jittering will take place, and all
 reflections will appear sharp even when they should be diffuse.
 This may be desirable when used in combination with image sampling
@@ -365,15 +365,14 @@ accuracy and rendering time.
 .TP
 .BR -bv
 Boolean switch for back face visibility.
-With this switch off, back faces of opaque objects will be invisible
-to all rays.
+With this switch off, back faces of all objects will be invisible
+to view rays.
 This is dangerous unless the model was constructed such that
-all surface normals on opaque objects face outward.
+all surface normals face outward.
 Although turning off back face visibility does not save much
 computation time under most circumstances, it may be useful as a
 tool for scene debugging, or for seeing through one-sided walls from
 the outside.
-This option has no effect on transparent or translucent materials.
 .TP
 .BI -av " red grn blu"
 Set the ambient value to a radiance of
@@ -571,7 +570,8 @@ When "on", pure Monte Carlo sampling is used in all ca
 .TP
 .BI -lr \ N
 Limit reflections to a maximum of
-.I N.
+.I N,
+if N is a positive integer.
 If
 .I N
 is zero, then Russian roulette is used for ray
@@ -579,7 +579,7 @@ termination, and the
 .I -lw
 setting (below) must be positive.
 If N is a negative integer, then this sets the upper limit
-of reflections past which Russian roulette will not be used.
+of reflections past which Russian roulette will be used.
 In scenes with dielectrics and total internal reflection,
 a setting of 0 (no limit) may cause a stack overflow.
 .TP