diff --git a/python/lsst/obs/lsst/script/write_lsstcam_manual_defects.py b/python/lsst/obs/lsst/script/write_lsstcam_manual_defects.py
new file mode 100644
index 00000000..208188fa
--- /dev/null
+++ b/python/lsst/obs/lsst/script/write_lsstcam_manual_defects.py
@@ -0,0 +1,239 @@
+# This file is part of obs_lsst.
+#
+# Developed for the LSST Data Management System.
+# This product includes software developed by the LSST Project
+# (https://www.lsst.org).
+# See the COPYRIGHT file at the top-level directory of this distribution
+# for details of code ownership.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+import re
+import os
+import dateutil.parser
+from lsst.ip.isr import Defects
+from lsst.geom import Box2I, Point2I, Extent2I
+import lsst.utils
+from lsst.obs.lsst import LsstCam
+
+
+camera = LsstCam().getCamera()
+
+data_root = lsst.utils.getPackageDir("obs_lsst_data")
+
+valid_start = "1970-01-01T00:00:00"
+valid_date = dateutil.parser.parse(valid_start)
+datestr = "".join(re.split(r"[:-]", valid_date.isoformat()))
+
+total_masked_pixels = 0
+
+for det in camera:
+    print("Building manual defects from detector ", det.getName(), det.getId())
+    name = det.getName()
+    raft, sensor = name.split("_")
+
+    out_path = os.path.join(data_root, "lsstCam", "manual_defects", name.lower())
+    os.makedirs(out_path, exist_ok=True)
+    out_file = os.path.join(out_path, f"{datestr}.ecsv")
+
+    if os.path.isfile(out_file):
+        os.remove(out_file)
+
+    box_xywh = []
+
+    if det.getId() == 0:
+        box_xywh.extend(
+            (
+                # Scratch on detector.
+                (2345, 0, 125, 4000),
+            ),
+        )
+    elif det.getId() == 9:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2900, 2000, 10, 1142),
+                (3071, 2000, 7, 690),
+            ),
+        )
+    elif det.getId() == 15:
+        box_xywh.extend(
+            (
+                # Arcanum columnae
+                (2086, 2000, 12, 2000),
+            ),
+        )
+    elif det.getId() == 24:
+        box_xywh.extend(
+            (
+                # Ardenti negans
+                (1097, 2000, 15, 2000),
+            ),
+        )
+    elif det.getId() == 25:
+        box_xywh.extend(
+            (
+                # Negativa affirmativa
+                (1241, 0, 2, 2000),
+            ),
+        )
+    elif det.getId() == 34:
+        box_xywh.extend(
+            (
+                # Arcanum columnae
+                (3026, 0, 11, 3355),
+            ),
+        )
+    elif det.getId() == 52:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (1329, 2000, 9, 1590),
+            ),
+        )
+    elif det.getId() == 67:
+        box_xywh.extend(
+            (
+                # Ardenti negans
+                (3753, 2000, 30, 2000),
+                # Ardenti negans imperfecta
+                (407, 1480, 11, 520),
+            ),
+        )
+    elif det.getId() == 76:
+        box_xywh.extend(
+            (
+                # Negativa affirmativa
+                (3346, 2000, 4, 2000),
+            ),
+        )
+    elif det.getId() == 83:
+        box_xywh.extend(
+            (
+                # Negativa affirmativa
+                (1425, 0, 2, 2000),
+            ),
+        )
+    elif det.getId() == 90:
+        box_xywh.extend(
+            (
+                # Ardenti negans
+                (3031, 0, 21, 2000),
+            ),
+        )
+    elif det.getId() == 105:
+        box_xywh.extend(
+            (
+                # Ardenti negans
+                (629, 2000, 21, 2000),
+            ),
+        )
+    elif det.getId() == 116:
+        box_xywh.extend(
+            (
+                # Thermometrum vestigium
+                (2380, 0, 4, 2000),
+                (2374, 450, 15, 15),
+                (2397, 0, 2, 2000),
+            ),
+        )
+    elif det.getId() == 117:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2585, 1640, 10, 360),
+                (2590, 0, 1, 2000),
+            ),
+        )
+    elif det.getId() == 127:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2840, 482, 13, 1518),
+            ),
+        )
+    elif det.getId() == 128:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2974, 2000, 14, 1700),
+            ),
+        )
+    elif det.getId() == 132:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2970, 2000, 13, 1086),
+            ),
+        )
+    elif det.getId() == 134:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (383, 2000, 11, 1468),
+            ),
+        )
+    elif det.getId() == 139:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (3574, 2000, 13, 402),
+            ),
+        )
+    elif det.getId() == 145:
+        box_xywh.extend(
+            (
+                # Ardenti negans
+                (978, 18, 19, 2000),
+            ),
+        )
+    elif det.getId() == 154:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (2049, 225, 10, 1775),
+            ),
+        )
+    elif det.getId() == 155:
+        box_xywh.extend(
+            (
+                # Ardenti negans imperfecta
+                (1447, 2000, 15, 700),
+            ),
+        )
+
+    bboxes = [
+        Box2I(corner=Point2I(x, y), dimensions=Extent2I(w, h))
+        for x, y, w, h in box_xywh
+    ]
+
+    for x, y, w, h in box_xywh:
+        total_masked_pixels += w*h
+
+    defects = Defects(bboxes)
+
+    defects.updateMetadata(
+        OBSTYPE="manual_defects",
+        camera=camera,
+        detector=det,
+        setCalibId=True,
+        setCalibInfo=True,
+        CALIBDATE=valid_start,
+        INSTRUME="LSSTCam",
+        CALIB_ID=(f"raftName={raft} detectorName={name} "
+                  f"detector={det.getId()} calibDate={valid_start}"),
+    )
+
+    defects.writeText(out_file)
+
+print("Total number of manually masked pixels masked will be ", total_masked_pixels)