diff --git a/xrtpy/image_correction/remove_lightleak.py b/xrtpy/image_correction/remove_lightleak.py
index f03f8ed2..eeb13a5f 100644
--- a/xrtpy/image_correction/remove_lightleak.py
+++ b/xrtpy/image_correction/remove_lightleak.py
@@ -98,22 +98,22 @@ def _get_stray_light_phase(date_obs):
 def _select_lightleak_file(filter_wheel_1, filter_wheel_2, date):
     phase = _get_stray_light_phase(date)
     file_dict = {
-        ("open", "al mesh"): {
+        ("open", "al_mesh"): {
             2: "term_p2am_20150718_160913.fits",
             3: "term_p3am_20170808_180126.fits",
             4: "term_p4am_20180712_171919.fits",
             5: "term_p5am_20220709_180901.fits",
         },
-        ("al poly", "open"): {
+        ("al_poly", "open"): {
             2: "term_p2ap_20150620_172818.fits",
             3: "term_p3ap_20170809_183821.fits",
             4: "term_p4ap_20180712_171928.fits",
             5: "term_p5ap_20220709_180910.fits",
         },
-        ("c poly", "open"): {
+        ("c_poly", "open"): {
             2: "term_p2cp_20150620_190645.fits",
         },
-        ("open", "ti poly"): {
+        ("open", "ti_poly"): {
             1: "term_p1tp_20140515_182503.fits",
             2: "term_p2tp_20150718_160921.fits",
         },
@@ -206,9 +206,9 @@ def remove_lightleak(in_map, scale=1.0, leak_map=None):
         warnings.warn("HISTORY indicates light leak subtraction already done on image.")  # noqa: B028
 
     if leak_map is None:
-        leak_filename = _select_lightleak_file(
-            *in_map.measurement.split("-"), in_map.date
-        )
+        fw1 = in_map.meta["EC_FW1_"]
+        fw2 = in_map.meta["EC_FW2_"]
+        leak_filename = _select_lightleak_file(fw1, fw2, in_map.date)
 
         # NOTE: This function is being defined inline because the filename is only known once
         # the date and filter wheel combination are known.