diff --git a/imagewidget.cpp b/imagewidget.cpp
index 1b0849c..0a5ab5a 100644
--- a/imagewidget.cpp
+++ b/imagewidget.cpp
@@ -497,6 +497,7 @@ void ImageWidgetGL::paintGL()
     QBrush highlight = style()->standardPalette().highlight();
 
     f->glClear(GL_COLOR_BUFFER_BIT);
+    f->glBlendFunc(GL_ONE, GL_ZERO);
     if(m_showThumbnails)
     {
         m_vaoThumb->bind();