Merge pull request #113 from lsst/tickets/SP-2869

SP-2869: NB (and docs) unpopulated image mask planes

Author: plazas

DP1/200_Data_Products/202_Images/202_6_Pixel_mask_planes.ipynb

@@ -24,7 +24,7 @@
     "Data Release: [Data Preview 1](https://dp1.lsst.io/)\\\n",
     "Container Size: large \\\n",
     "LSST Science Pipelines version: r29.2. \\\n",
-    "Last verified to run: 2025-12-08 \\\n",
+    "Last verified to run: 2026-01-28 \\\n",
     "Repository: [github.com/lsst/tutorial-notebooks](https://github.com/lsst/tutorial-notebooks) \\\n",
     "DOI: [10.11578/rubin/dc.20250909.20](https://doi.org/10.11578/rubin/dc.20250909.20\\) "
    ]
@@ -312,10 +312,8 @@
     "| **INTRP** | Retain | Interpolated pixel (typically over `BAD`, `SAT`, or `CR`). Safe to retain for most analyses. |\n",
     "| **SUSPECT** | Conditional | Near-saturation or uncertain response. Keep or reject depending on science goals. |\n",
     "| **EDGE / SENSOR_EDGE** | Exclude | Marks detector edges; can propagate into coadds. |\n",
-    "| **NO_DATA** | Exclude | Region with no valid data (chip gap, missing coverage, failed amplifier). |\n",
     "| **CROSSTALK** | Retain | Electronic signal induced by a bright source in a neighboring amplifier. |\n",
-    "| **ITL_DIP** | Exclude | \"ITL dip\" artifact: dark vertical trails from bright sources on ITL CCDs. |\n",
-    "| **VIGNETTED** | Conditional | Lower-quality data due to vignetting; may be included if weighted properly. |"
+    "| **ITL_DIP** | Exclude | \"ITL dip\" artifact: dark vertical trails from bright sources on ITL CCDs. |"
    ]
   },
   {
@@ -360,6 +358,28 @@
     "> **Table 4:** Key mask planes in `deep_coadd`."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "49802322-2987-489a-b0c6-956d821a4a75",
+   "metadata": {},
+   "source": [
+    "### 2.3. Mask planes not populated in DP1\n",
+    "\n",
+    "In DP1, several mask planes defined by the LSST Science Pipelines are not populated in either `visit_image` or `deep_coadd` products.\n",
+    "This is expected and reflects DP1-specific processing, camera geometry, and pipeline configuration, and may differ in future data releases.\n",
+    "\n",
+    "#### 2.3.1 Visit images\n",
+    "The following planes are not set in DP1 `visit_image`s:\n",
+    "\n",
+    "`CLIPPED`, `DETECTED_NEGATIVE`, `INEXACT_PSF`, `INJECTED`, `INJECTED_TEMPLATE`, `NO_DATA`,\n",
+    "`REJECTED`, `SAT_TEMPLATE`, `SENSOR_EDGE`, `STREAK`, `UNMASKEDNAN`, `VIGNETTED`.\n",
+    "\n",
+    "#### 2.3.2 Deep coadd images\n",
+    "The following planes are not set in DP1 `deep_coadd`s:\n",
+    "\n",
+    "`BAD`, `CROSSTALK`, `DETECTED_NEGATIVE`, `ITL_DIP`, `NOT_DEBLENDED`, `STREAK`, `SUSPECT`, `UNMASKEDNAN`, `VIGNETTED`."
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "f062ce6d-9d48-46f0-8c10-5c9004658f61",