diff --git a/csst_common/data_manager.py b/csst_common/data_manager.py
index bc5fb597ca784281c79e4f50a336b5423881c5d7..a54004d78766bb34dbd6f5a88ab549219c38ff7b 100644
--- a/csst_common/data_manager.py
+++ b/csst_common/data_manager.py
@@ -1017,6 +1017,7 @@ class CsstMsFile(dict):
 
         self.filename = os.path.basename(filepath)
         self.dir_l0 = os.path.dirname(filepath)
+        print("parsing", filepath)
         # parse filename
         pattern = re.compile(
             r"(?P<telescope>[A-Z]+)_"
@@ -1029,7 +1030,7 @@ class CsstMsFile(dict):
             r"(?P<detector>[0-9]{2})_"
             r"L(?P<level>[0-9]{1})_"
             r"V(?P<version>[0-9]{2})"
-            r".(?P<ext>[a-z]{4})"
+            r"(?P<ext>[a-zA-Z._]+)"
         )
         mo = re.fullmatch(pattern, self.filename)
         assert mo is not None
@@ -1082,3 +1083,5 @@ class CsstMsFile(dict):
 #     "L1/MSC/SCI/62173/10160000108/CSST_MSC_MS_SCI_20290206174352_20290206174622_10160000108_21_L1_V01.fits")
 #
 # file = CsstMsFile.from_l1id(id=17796, dfs_root="/share/dfs")
+# file = CsstMsFile.from_l1id(id=12853, dfs_root="/share/dfs")
+# CsstMsFile("CSST_MSC_MS_SCI_20280716184136_20280716184406_10160000099_14_L1_V01_IMG.fits")