diff --git a/scripts/mkphotos.sh b/scripts/mkphotos.sh
index 4b26895..28befc9 100644
--- a/scripts/mkphotos.sh
+++ b/scripts/mkphotos.sh
@@ -4,6 +4,7 @@
 
 DIR="$(basename "$PWD")"
 TITLE="$(basename "$PWD" |sed 's/unlisted-//g' | cut -d"_" -f2- | tr '-' ' ')"
+PROCS="$(sysctl -n hw.ncpuonline)"
 
 mkdir -p thm mid
 
@@ -70,7 +71,7 @@ do
         echo "</tr><tr>"
     fi
 
-    while [ $(pgrep convert | wc -l) -ge 15 ]
+    while [ $(pgrep convert | wc -l) -gt $PROCS ]
     do sleep 0.3; done
 
 done