diff --git a/.gitignore b/.gitignore
index fb6835d..a903a4f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@
 /.pytest_cache/
 /ndbioimage/_version.py
 /ndbioimage/jars
+/tests/files/*
diff --git a/ndbioimage/__init__.py b/ndbioimage/__init__.py
index aa86009..e0e0034 100755
--- a/ndbioimage/__init__.py
+++ b/ndbioimage/__init__.py
@@ -521,6 +521,8 @@ class Imread(np.lib.mixins.NDArrayOperatorsMixin, metaclass=ABCMeta):
         self.cache = DequeDict(16)
         self._frame_decorator = None
         self.frameoffset = 0, 0  # how far apart the centers of frame and sensor are
+        self.flags = dict(C_CONTIGUOUS=False, F_CONTIGUOUS=False, OWNDATA=False, WRITEABLE=False,
+                          ALIGNED=False, WRITEBACKIFCOPY=False, UPDATEIFCOPY=False)
 
         self.open()
 
@@ -721,7 +723,7 @@ class Imread(np.lib.mixins.NDArrayOperatorsMixin, metaclass=ABCMeta):
             s.append(f'pixel size:    {1000 * self.pxsize_um:.2f} nm')
         if self.zstack and self.deltaz_um:
             s.append(f'z-interval:    {1000 * self.deltaz_um:.2f} nm')
-        if self.exposuretime_s:
+        if self.exposuretime_s and not all(e is None for e in self.exposuretime_s):
             s.append(f'exposuretime:  {self.exposuretime_s[0]:.2f} s')
         if self.timeseries and self.timeinterval:
             s.append(f'time interval: {self.timeinterval:.3f} s')
diff --git a/ndbioimage/readers/seqread.py b/ndbioimage/readers/seqread.py
index 50f64e7..380fabd 100644
--- a/ndbioimage/readers/seqread.py
+++ b/ndbioimage/readers/seqread.py
@@ -41,7 +41,7 @@ class Reader(Imread, ABC):
 
     @staticmethod
     def _can_open(path):
-        return isinstance(path, Path) and path.suffix == ""
+        return isinstance(path, Path) and path.is_dir()
 
     @cached_property
     def ome(self):
@@ -107,7 +107,7 @@ class Reader(Imread, ABC):
         return ome
 
     def open(self):
-        if not self.path.name.startswith("Pos"):
+        if re.match(r'(?:\d+\-)?Pos.*', self.path.name) is None:
             path = self.path / f"Pos{self.series}"
         else:
             path = self.path
diff --git a/pyproject.toml b/pyproject.toml
index c7f638c..adf0a4b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "ndbioimage"
-version = "2023.7.2"
+version = "2023.7.3"
 description = "Bio image reading, metadata and some affine registration."
 authors = ["W. Pomp <w.pomp@nki.nl>"]
 license = "GPLv3"