diff --git a/src/xrt/auxiliary/tracking/t_calibration.cpp b/src/xrt/auxiliary/tracking/t_calibration.cpp
index 7756eefd8..4061c65d5 100644
--- a/src/xrt/auxiliary/tracking/t_calibration.cpp
+++ b/src/xrt/auxiliary/tracking/t_calibration.cpp
@@ -477,6 +477,7 @@ process_stereo_samples(class Calibration &c, int cols, int rows)
 	CalibrationRawData raw = {};
 	assert(raw.isDataStorageValid());
 
+	raw.use_fisheye = c.use_fisheye;
 	raw.image_size_pixels.w = image_size.width;
 	raw.image_size_pixels.h = image_size.height;
 	raw.new_image_size_pixels.w = new_image_size.width;
diff --git a/src/xrt/auxiliary/tracking/t_file.cpp b/src/xrt/auxiliary/tracking/t_file.cpp
index 5030c2eb8..efe96ff9c 100644
--- a/src/xrt/auxiliary/tracking/t_file.cpp
+++ b/src/xrt/auxiliary/tracking/t_file.cpp
@@ -79,16 +79,13 @@ t_settings_stereo_refine(struct t_settings_stereo_raw *raw_data,
 	data.new_image_size_pixels = raw.new_image_size_pixels;
 	raw.disparity_to_depth_mat.copyTo(data.disparity_to_depth_mat);
 
-	//! @todo Load from file.
-	bool use_fisheye = false;
-
 	//! @todo Scale Our intrinsics if the frame size we request
 	//              calibration for does not match what was saved
 	cv::Size image_size(raw.image_size_pixels.w, raw.image_size_pixels.h);
 
 	// Generate undistortion maps - handle fisheye or rectilinear sources
 
-	if (use_fisheye) {
+	if (raw.use_fisheye) {
 		cv::fisheye::initUndistortRectifyMap(
 		    raw.l_intrinsics_mat,         // cameraMatrix
 		    raw.l_distortion_fisheye_mat, // distCoeffs
@@ -188,8 +185,8 @@ t_settings_stereo_load_v1(FILE *calib_file,
 	read_cv_mat(calib_file, &raw.r_intrinsics_mat, "r_intrinsics"); // 3 x 3
 	read_cv_mat(calib_file, &raw.l_distortion_mat, "l_distortion"); // 1 x 5
 	read_cv_mat(calib_file, &raw.r_distortion_mat, "r_distortion"); // 1 x 5
-	read_cv_mat(calib_file, &raw.l_distortion_fisheye_mat, "l_distortion_fisheye");
-	read_cv_mat(calib_file, &raw.r_distortion_fisheye_mat, "r_distortion_fisheye");
+	read_cv_mat(calib_file, &raw.l_distortion_fisheye_mat, "l_distortion_fisheye"); // 4 x 1
+	read_cv_mat(calib_file, &raw.r_distortion_fisheye_mat, "r_distortion_fisheye"); // 4 x 1
 	read_cv_mat(calib_file, &raw.l_rotation_mat, "l_rotation"); // 3 x 3
 	read_cv_mat(calib_file, &raw.r_rotation_mat, "r_rotation"); // 3 x 3
 	read_cv_mat(calib_file, &l_translation_dummy, "l_translation"); // empty
@@ -224,6 +221,14 @@ t_settings_stereo_load_v1(FILE *calib_file,
 	if (!read_cv_mat(calib_file, &raw.camera_fundamental_mat, "fundamental")) {
 		fprintf(stderr, "\tRe-run calibration!\n");
 	}
+
+	cv::Mat mat_use_fisheye = {};
+	if (!read_cv_mat(calib_file, &mat_use_fisheye, "use_fisheye")) {
+		raw.use_fisheye = false;
+		fprintf(stderr, "\tRe-run calibration!\n");
+	} else {
+		raw.use_fisheye = mat_use_fisheye.at<float>(0, 0) != 0.0;
+	}
 	// clang-format on
 
 	if (raw.camera_translation_mat.size() == cv::Size(3, 1)) {
@@ -292,6 +297,11 @@ t_file_save_raw_data(FILE *calib_file, struct t_settings_stereo_raw *raw_data)
 	write_cv_mat(calib_file, &raw.camera_essential_mat);
 	write_cv_mat(calib_file, &raw.camera_fundamental_mat);
 
+	cv::Mat mat_use_fisheye;
+	mat_use_fisheye.create(1, 1, CV_32F);
+	mat_use_fisheye.at<float>(0, 0) = raw.use_fisheye;
+	write_cv_mat(calib_file, &mat_use_fisheye);
+
 	return true;
 }
 
diff --git a/src/xrt/auxiliary/tracking/t_tracking.h b/src/xrt/auxiliary/tracking/t_tracking.h
index e9e66baf8..3ca1305e2 100644
--- a/src/xrt/auxiliary/tracking/t_tracking.h
+++ b/src/xrt/auxiliary/tracking/t_tracking.h
@@ -134,6 +134,9 @@ struct t_settings_stereo_raw
 	double r_rotation[3][3];
 	//! Right projection matrix in the new (rectified) coordinate systems.
 	double r_projection[3][4];
+
+	//! Use fisheye distortion.
+	bool use_fisheye;
 };
 
 /*!