diff --git a/cmd/mtwebmapper/tilesupdater.go b/cmd/mtwebmapper/tilesupdater.go
index cc44edb..a4f9d2f 100644
--- a/cmd/mtwebmapper/tilesupdater.go
+++ b/cmd/mtwebmapper/tilesupdater.go
@@ -179,6 +179,8 @@ func (tu *tileUpdater) doUpdates() {
 
 	bth := common.NewBaseTileHash()
 
+	baseDir := filepath.Join(tu.mapDir, "8")
+
 	for {
 		tu.cond.L.Lock()
 		for len(tu.changes) == 0 {
@@ -188,8 +190,6 @@ func (tu *tileUpdater) doUpdates() {
 		tu.changes = map[xz]struct{}{}
 		tu.cond.L.Unlock()
 
-		baseDir := filepath.Join(tu.mapDir, "8")
-
 		jobs := make(chan *xzc)
 		var done sync.WaitGroup