diff --git a/dap/algos/streakfind.py b/dap/algos/streakfind.py
index 981a214..6e7ecf6 100644
--- a/dap/algos/streakfind.py
+++ b/dap/algos/streakfind.py
@@ -168,14 +168,16 @@ def _calc_streakfinder_analysis(results, snr, mask):
 
     if crop_roi is None:
         region = snr
+        region_mask = mask
     else:
         region = snr[crop_roi[0]: crop_roi[1], crop_roi[2]: crop_roi[3]]
-    peaks = detect_peaks(region, mask, peaks_structure.rank, peak_vmin,
+        region_mask = mask[crop_roi[0]: crop_roi[1], crop_roi[2]: crop_roi[3]]
+    peaks = detect_peaks(region, region_mask, peaks_structure.rank, peak_vmin,
                          num_threads=num_threads)
-    peaks = filter_peaks(peaks, region, mask, peaks_structure, peak_vmin, npts,
+    peaks = filter_peaks(peaks, region, region_mask, peaks_structure, peak_vmin, npts,
                         num_threads=num_threads)
     
-    detected = detect_streaks(peaks, region, mask, streaks_structure, xtol, streak_vmin, min_size,
+    detected = detect_streaks(peaks, region, region_mask, streaks_structure, xtol, streak_vmin, min_size,
                               lookahead, nfa, num_threads=num_threads)
     del peaks