diff --git a/sphinx_autobuild/__main__.py b/sphinx_autobuild/__main__.py
index 99655e0..347f2ce 100644
--- a/sphinx_autobuild/__main__.py
+++ b/sphinx_autobuild/__main__.py
@@ -50,11 +50,14 @@ def main(argv=()):
     )
 
     watch_dirs = [src_dir] + args.additional_watched_dirs
-    ignore_dirs = args.ignore + [out_dir, args.warnings_file, args.doctree_dir]
-    ignore_handler = IgnoreFilter(
-        [Path(p).as_posix() for p in ignore_dirs if p],
-        args.re_ignore,
-    )
+    ignore_dirs = [
+        *args.ignore,
+        out_dir,
+        args.warnings_file,
+        args.doctree_dir,
+    ]
+    ignore_dirs = list(filter(None, ignore_dirs))
+    ignore_handler = IgnoreFilter(ignore_dirs, args.re_ignore)
     app = _create_app(watch_dirs, ignore_handler, builder, out_dir, url_host)
 
     if not args.no_initial_build:
diff --git a/sphinx_autobuild/filter.py b/sphinx_autobuild/filter.py
index 03a6b34..2b61ca4 100644
--- a/sphinx_autobuild/filter.py
+++ b/sphinx_autobuild/filter.py
@@ -2,12 +2,14 @@
 
 import fnmatch
 import re
+from pathlib import Path
 
 
 class IgnoreFilter:
     def __init__(self, regular, regex_based):
         """Prepare the function that determines whether a path should be ignored."""
-        self.regular_patterns = [*dict.fromkeys(regular)]
+        normalised_paths = [Path(p).resolve().as_posix() for p in regular]
+        self.regular_patterns = list(dict.fromkeys(normalised_paths))
         self.regex_based_patterns = [*map(re.compile, dict.fromkeys(regex_based))]
 
     def __repr__(self):
@@ -18,6 +20,7 @@ def __repr__(self):
 
     def __call__(self, path):
         """Determine if 'path' should be ignored."""
+        path = Path(path).resolve().as_posix()
         # Any regular pattern matches.
         for pattern in self.regular_patterns:
             # separators are normalised before creating the IgnoreFilter