diff --git a/notebooks/photometry/01.04.01-image-segmentation-simulated-image.ipynb b/notebooks/photometry/01.04.01-image-segmentation-simulated-image.ipynb
index 6b9c64d..918c135 100644
--- a/notebooks/photometry/01.04.01-image-segmentation-simulated-image.ipynb
+++ b/notebooks/photometry/01.04.01-image-segmentation-simulated-image.ipynb
@@ -36,6 +36,7 @@
     "from photutils.datasets import make_100gaussians_image, make_gaussian_sources_image, make_noise_image\n",
     "from photutils.detection import find_peaks, DAOStarFinder\n",
     "from photutils.segmentation import detect_sources, make_2dgaussian_kernel, SourceCatalog\n",
+    "from photutils.utils import make_random_cmap\n",
     "\n",
     "plt.style.use('../photutils_notebook_style.mplstyle')"
    ]
diff --git a/notebooks/photometry/01.04.02-image-segmentation-XDF.ipynb b/notebooks/photometry/01.04.02-image-segmentation-XDF.ipynb
index 3710678..d078971 100644
--- a/notebooks/photometry/01.04.02-image-segmentation-XDF.ipynb
+++ b/notebooks/photometry/01.04.02-image-segmentation-XDF.ipynb
@@ -370,6 +370,8 @@
     "                            marker=\"s\", facecolor=\"none\", edgecolor=\"cyan\", s=200, \n",
     "                            alpha=0.5, label=\"DAOFind\")\n",
     "\n",
+    "    rand_cmap = make_random_cmap()\n",
+    "    rand_cmap.set_under('black')\n",
     "    sub_axs[\"segm\"].imshow(segm.data[slc], cmap=rand_cmap, vmin=1, vmax=len(sources_findpeaks), origin=\"lower\")\n",
     "    src_id = src[\"source_id\"]\n",
     "    # ax.text(2, 2, str(src_id), color='w', va='top')\n",