--- ray/doc/man/man1/gensky.1	2003/05/22 16:14:24	1.2
+++ ray/doc/man/man1/gensky.1	2019/11/07 23:16:17	1.7
@@ -1,4 +1,4 @@
-.\" RCSid "$Id"
+.\" RCSid "$Id: gensky.1,v 1.7 2019/11/07 23:16:17 greg Exp $"
 .TH GENSKY 1 4/24/98 RADIANCE
 .SH NAME
 gensky - generate a RADIANCE description of the sky
@@ -37,14 +37,14 @@ YST   PST   MST   CST   EST   GMT
  9     8     7     6     5     0
 
 CET   EET   AST   GST   IST   JST  NZST
--1    -2    -3    -4    -5.5  -9   -12
+\-1    \-2    \-3    \-4    \-5.5  \-9   \-12
 
 Daylight savings time:
 YDT   PDT   MDT   CDT   EDT   BST
- 8     7     6     5     4     -1
+ 8     7     6     5     4     \-1
 
 CEST  EEST  ADT   GDT   IDT   JDT  NZDT
- -2    -3   -4    -5   -6.5   -10  -13
+ \-2    \-3   \-4    \-5   \-6.5   \-10  \-13
 .fi
 .PP
 If the time is preceded by a plus sign ('+'), then it is interpreted
@@ -97,13 +97,18 @@ suggests an ambient value in a comment at the beginnin
 description to use with the
 .I \-av
 option of the RADIANCE rendering programs.
-(See rview(1) and rpict(1).)
+(See rvu(1) and rpict(1).)
 This value is the cosine-weighted radiance of the sky in
 watts/steradian/meter2.
 .PP
 .I Gensky
 supports the following options.
 .TP 10n
+.BR \-y \ year
+If the year is specified, a more accurate solar position algorithm
+[Michalsky 1988] will be used in place of the formula in the IES
+Lighting Handbook.
+.TP
 .BR \-s
 Sunny sky without sun.
 The sky distribution will correspond to a standard CIE clear day.
@@ -211,20 +216,20 @@ degrees west of Greenwich.
 (Use negative angle for east.)
 This is used in the calculation of solar time.
 Be sure to give the correct longitude also!
-If solar time is given directly, then this option has no effect.
+If a time zone or solar time is given directly, then this option has no effect.
 .SH EXAMPLE
 To produce a sunny sky for July 4th at 2:30pm Eastern daylight time at a
 site latitude of 42 degrees, 89 degrees west longitude:
 .IP "" .2i
-gensky 7 4 14:30EDT +s -a 42 -o 89
+gensky 7 4 14:30EDT +s \-a 42 \-o 89
 .PP
 To produce a sunny sky distribution for a specific sun position but
 without the sun description:
 .IP "" .2i
-gensky -ang 23 -40 -s
+gensky \-ang 23 \-40 \-s
 .SH FILES
 /usr/local/lib/ray/skybright.cal
 .SH AUTHOR
 Greg Ward
 .SH "SEE ALSO"
-rpict(1), rview(1), xform(1)
+rpict(1), rvu(1), xform(1)