diff --git a/grum/mainwin.py b/grum/mainwin.py
index a37de16..ec70f60 100644
--- a/grum/mainwin.py
+++ b/grum/mainwin.py
@@ -110,7 +110,7 @@ class MainWindow(QMainWindow):
         """
         Create a new image <name> using the configuration dict <cfg>.
         The configuration is forwarded to the constructor of ImageDescription.
-        Allowed keys are: title, xlabel, ylabel, image.
+        Allowed keys are: title, xlabel, ylabel, image, levels, cmap.
         """
         desc = self.add_new_desc_to_list(ImageDescription, name, cfg)
         if self.menu_settings.checkboxes["Open new plots"].isChecked():