diff --git a/TimeSeries.pm b/TimeSeries.pm
index 3cded4b..9311873 100644
--- a/TimeSeries.pm
+++ b/TimeSeries.pm
@@ -33,7 +33,7 @@ use HTTP::Date qw(parse_date);
 use Time::Local qw(timegm_nocheck);
 use POSIX qw(strftime);
 
-our $VERSION = do { my @r=(q$Revision: 1.19 $=~/\d+/g);sprintf "%d."."%02d"x$#r,@r};
+our $VERSION = do { my @r=(q$Revision: 1.20 $=~/\d+/g);sprintf "%d."."%02d"x$#r,@r};
 
 our $debug;
 
@@ -324,7 +324,7 @@ sub plot {
     my ($self) = @_;
     #print Dumper($self);
 
-    my ($datafh, $datafn) = tempfile("tsplotXXXXXXXX", UNLINK => 1);
+    my ($datafh, $datafn) = tempfile("tsplotXXXXXXXX", UNLINK => !$self->{keeptempfiles});
     for my $i (@{$self->{data}}) {
 	my $time = $i->[0];
 	my $data = $i->[1];
@@ -345,12 +345,12 @@ sub plot {
     }
     close($datafh);
 
-    my ($ctlfh, $ctlfn) = tempfile(UNLINK => 1);
-    my ($psfh, $psfn) = tempfile(UNLINK => 1);
+    my ($ctlfh, $ctlfn) = tempfile(UNLINK => !$self->{keeptempfiles});
+    my ($psfh, $psfn) = tempfile(UNLINK => !$self->{keeptempfiles});
 
     # generic settings
 
-    print $ctlfh "set term postscript color\n";
+    print $ctlfh "set term postscript color solid 10\n";
     print $ctlfh "set output '$psfn'\n";
     print $ctlfh "set data style $self->{style}\n";
     print $ctlfh "set grid\n";