diff --git a/zesje/pregrader.py b/zesje/pregrader.py
index 4954bc8a7d2083f782ce0c03e42c74284e2e12f7..26b295848b344e5a1b386e5727d35ccac6aaead1 100644
--- a/zesje/pregrader.py
+++ b/zesje/pregrader.py
@@ -22,7 +22,11 @@ def add_feedback_to_solution(sub, exam, page, page_img, corner_keypoints):
     """
     problems_on_page = [problem for problem in exam.problems if problem.widget.page == page]
 
-    top_left_point, fixed_corner_keypoints = fix_corner_markers(corner_keypoints, page_img.shape)
+    fixed_corner_keypoints = fix_corner_markers(corner_keypoints, page_img.shape)
+
+    x_min = min(point[0] for point in fixed_corner_keypoints)
+    y_min = min(point[1] for point in fixed_corner_keypoints)
+    top_left_point = (x_min, y_min)
 
     for problem in problems_on_page:
         sol = Solution.query.filter(Solution.problem_id == problem.id, Solution.submission_id == sub.id).one_or_none()