diff --git a/pyerrors/correlators.py b/pyerrors/correlators.py
index 25de56b4..a8d2361e 100644
--- a/pyerrors/correlators.py
+++ b/pyerrors/correlators.py
@@ -540,7 +540,7 @@ class Corr:
             on the configurations in obs[i].idl.
         """
         if self.N != 1:
-            raise Exception("Reweighting only implemented for one-dimensional correlators.")
+            raise ValueError("Reweighting only implemented for one-dimensional correlators.")
         new_content = []
         for t_slice in self.content:
             if _check_for_none(self, t_slice):
@@ -560,11 +560,11 @@ class Corr:
             Parity quantum number of the correlator, can be +1 or -1
         """
         if self.N != 1:
-            raise Exception("T_symmetry only implemented for one-dimensional correlators.")
+            raise ValueError("T_symmetry only implemented for one-dimensional correlators.")
         if not isinstance(partner, Corr):
-            raise Exception("T partner has to be a Corr object.")
+            raise TypeError("T partner has to be a Corr object.")
         if parity not in [+1, -1]:
-            raise Exception("Parity has to be +1 or -1.")
+            raise ValueError("Parity has to be +1 or -1.")
         T_partner = parity * partner.reverse()
 
         t_slices = []
@@ -723,7 +723,7 @@ class Corr:
             guess for the root finder, only relevant for the root variant
         """
         if self.N != 1:
-            raise Exception('Correlator must be projected before getting m_eff')
+            raise ValueError('Correlator must be projected before getting m_eff')
         if variant == 'log':
             newcontent = []
             for t in range(self.T - 1):
@@ -844,7 +844,7 @@ class Corr:
             if self.prange:
                 plateau_range = self.prange
             else:
-                raise Exception("no plateau range provided")
+                raise ValueError("no plateau range provided")
         if self.N != 1:
             raise ValueError("Correlator must be projected before getting a plateau.")
         if (all([self.content[t] is None for t in range(plateau_range[0], plateau_range[1] + 1)])):
diff --git a/pyerrors/covobs.py b/pyerrors/covobs.py
index f7722f8f..006c6aae 100644
--- a/pyerrors/covobs.py
+++ b/pyerrors/covobs.py
@@ -22,17 +22,17 @@ class Covobs:
         """
         self._set_cov(cov)
         if '|' in name:
-            raise Exception("Covobs name must not contain replica separator '|'.")
+            raise ValueError("Covobs name must not contain replica separator '|'.")
         self.name = name
         if grad is None:
             if pos is None:
                 if self.N == 1:
                     pos = 0
                 else:
-                    raise Exception('Have to specify position of cov-element belonging to mean!')
+                    raise ValueError('Have to specify position of cov-element belonging to mean!')
             else:
                 if pos > self.N:
-                    raise Exception(f'pos {pos} too large for covariance matrix with dimension {self.N}x{self.N}!')
+                    raise ValueError(f'pos {pos} too large for covariance matrix with dimension {self.N}x{self.N}!')
             self._grad = np.zeros((self.N, 1))
             self._grad[pos] = 1.
         else:
@@ -65,19 +65,19 @@ class Covobs:
         elif self._cov.ndim == 2:
             self.N = self._cov.shape[0]
             if self._cov.shape[1] != self.N:
-                raise Exception('Covariance matrix has to be a square matrix!')
+                raise ValueError('Covariance matrix has to be a square matrix!')
         else:
-            raise Exception('Covariance matrix has to be a 2 dimensional square matrix!')
+            raise ValueError('Covariance matrix has to be a 2 dimensional square matrix!')
 
         for i in range(self.N):
             for j in range(i):
                 if not self._cov[i][j] == self._cov[j][i]:
-                    raise Exception(f'Covariance matrix is non-symmetric for ({i}, {j})')
+                    raise ValueError(f'Covariance matrix is non-symmetric for ({i}, {j})')
 
         evals = np.linalg.eigvalsh(self._cov)
         for ev in evals:
             if ev < 0:
-                raise Exception('Covariance matrix is not positive-semidefinite!')
+                raise ValueError('Covariance matrix is not positive-semidefinite!')
 
     def _set_grad(self, grad):
         """ Set the gradient of the covobs
@@ -93,7 +93,7 @@ class Covobs:
         if self._grad.ndim in [0, 1]:
             self._grad = np.reshape(self._grad, (self.N, 1))
         elif self._grad.ndim != 2:
-            raise Exception('Invalid dimension of grad!')
+            raise ValueError('Invalid dimension of grad!')
 
     @property
     def cov(self):
diff --git a/pyerrors/fits.py b/pyerrors/fits.py
index f1b0a6c3..a952fce4 100644
--- a/pyerrors/fits.py
+++ b/pyerrors/fits.py
@@ -638,7 +638,7 @@ def total_least_squares(x, y, func, silent=False, **kwargs):
     if 'initial_guess' in kwargs:
         x0 = np.asarray(kwargs.get('initial_guess'), dtype=np.float64)
         if len(x0) != n_parms:
-            raise Exception(f'Initial guess does not have the correct length: {len(x0)} vs. {n_parms}')
+            raise ValueError(f'Initial guess does not have the correct length: {len(x0)} vs. {n_parms}')
     else:
         x0 = np.ones(n_parms, dtype=np.float64)
 
diff --git a/pyerrors/input/dobs.py b/pyerrors/input/dobs.py
index 3e5fcf63..27e13997 100644
--- a/pyerrors/input/dobs.py
+++ b/pyerrors/input/dobs.py
@@ -61,9 +61,9 @@ def _dict_to_xmlstring(d):
             elif not d[k]:
                 return '\n'
             else:
-                raise Exception('Type', type(d[k]), 'not supported in export!')
+                raise TypeError(f'Type {type(d[k]).__name__} not supported in export!')
     else:
-        raise Exception('Type', type(d), 'not supported in export!')
+        raise TypeError(f'Type {type(d).__name__} not supported in export!')
     return iters
 
 
@@ -124,11 +124,11 @@ def create_pobs_string(obsl, name, spec='', origin='', symbol=None, enstag=None)
     onames = [name.replace('|', '') for name in names]
     for o in obsl:
         if len(o.e_names) != 1:
-            raise Exception('You try to export dobs to obs!')
+            raise ValueError('You try to export dobs to obs!')
         if o.e_names[0] != ename:
-            raise Exception('You try to export dobs to obs!')
+            raise ValueError('You try to export dobs to obs!')
         if len(o.deltas.keys()) != nr:
-            raise Exception('Incompatible obses in list')
+            raise ValueError('Incompatible obses in list')
     od['observables'] = {}
     od['observables']['schema'] = {'name': 'lattobs', 'version': '1.0'}
     od['observables']['origin'] = {
@@ -143,7 +143,7 @@ def create_pobs_string(obsl, name, spec='', origin='', symbol=None, enstag=None)
     pd['name'] = name
     if enstag:
         if not isinstance(enstag, str):
-            raise Exception('enstag has to be a string!')
+            raise TypeError('enstag has to be a string!')
         pd['enstag'] = enstag
     else:
         pd['enstag'] = ename
@@ -151,9 +151,9 @@ def create_pobs_string(obsl, name, spec='', origin='', symbol=None, enstag=None)
     pd['array'] = []
     osymbol = 'cfg'
     if not isinstance(symbol, list):
-        raise Exception('Symbol has to be a list!')
+        raise TypeError('Symbol has to be a list!')
     if not (len(symbol) == 0 or len(symbol) == len(obsl)):
-        raise Exception(f'Symbol has to be a list of lenght 0 or {len(obsl)}!')
+        raise ValueError(f'Symbol has to be a list of length 0 or {len(obsl)}!')
     for s in symbol:
         osymbol += f' {s}'
     for r in range(nr):
@@ -365,7 +365,7 @@ def read_pobs(fname, full_output=False, gz=True, separator_insertion=None):
         elif isinstance(separator_insertion, str):
             name = name.replace(separator_insertion, f"|{separator_insertion}")
         else:
-            raise Exception("separator_insertion has to be string or int, is ", type(separator_insertion))
+            raise TypeError(f"separator_insertion has to be string or int, is {type(separator_insertion).__name__}")
         names.append(name)
         idl.append(idx)
     res = [Obs([d[i] for d in deltas], names, idl=idl) for i in range(len(deltas[0]))]
@@ -485,7 +485,7 @@ def import_dobs_string(content, full_output=False, separator_insertion=True):
                 elif isinstance(separator_insertion, str):
                     rname = rname.replace(separator_insertion, f"|{separator_insertion}")
                 else:
-                    raise Exception("separator_insertion has to be string or int, is ", type(separator_insertion))
+                    raise TypeError(f"separator_insertion has to be string or int, is {type(separator_insertion).__name__}")
                 if '|' in rname:
                     new_ename = rname[:rname.index('|')]
                 else:
@@ -657,9 +657,9 @@ def _dobsdict_to_xmlstring(d):
             elif not d[k]:
                 return '\n'
             else:
-                raise Exception('Type', type(d[k]), 'not supported in export!')
+                raise TypeError(f'Type {type(d[k]).__name__} not supported in export!')
     else:
-        raise Exception('Type', type(d), 'not supported in export!')
+        raise TypeError(f'Type {type(d).__name__} not supported in export!')
     return iters
 
 
@@ -752,9 +752,9 @@ def create_dobs_string(obsl, name, spec='dobs v1.0', origin='', symbol=None, who
     osymbol = ''
     if symbol:
         if not isinstance(symbol, list):
-            raise Exception('Symbol has to be a list!')
+            raise TypeError('Symbol has to be a list!')
         if not (len(symbol) == 0 or len(symbol) == len(obsl)):
-            raise Exception(f'Symbol has to be a list of lenght 0 or {len(obsl)}!')
+            raise ValueError(f'Symbol has to be a list of length 0 or {len(obsl)}!')
         osymbol = symbol[0]
         for s in symbol[1:]:
             osymbol += f' {s}'
diff --git a/pyerrors/input/hadrons.py b/pyerrors/input/hadrons.py
index 651a342b..f406080f 100644
--- a/pyerrors/input/hadrons.py
+++ b/pyerrors/input/hadrons.py
@@ -18,7 +18,7 @@ def _get_files(path, filestem, idl):
     files = list(filter(lambda x: x.startswith(filestem + "."), ls))
 
     if not files:
-        raise Exception('No files starting with', filestem, 'in folder', path)
+        raise FileNotFoundError(f'No files starting with {filestem} in folder {path}')
 
     def get_cnfg_number(n):
         return int(n.replace(".h5", "")[len(filestem) + 1:])  # From python 3.9 onward the safer 'removesuffix' method can be used.
@@ -298,7 +298,7 @@ def read_DistillationContraction_hd5(path, ens_id, diagrams=None, idl=None):
 
                 if n_file == 0:
                     if h5file["DistillationContraction/Metadata"].attrs.get("TimeSources")[0].decode() != "0...":
-                        raise Exception("Routine is only implemented for files containing inversions on all timeslices.")
+                        raise NotImplementedError("Routine is only implemented for files containing inversions on all timeslices.")
 
                     Nt = h5file["DistillationContraction/Metadata"].attrs.get("Nt")[0]
 
diff --git a/pyerrors/input/json.py b/pyerrors/input/json.py
index 1bad2330..ac12938b 100644
--- a/pyerrors/input/json.py
+++ b/pyerrors/input/json.py
@@ -568,7 +568,7 @@ def _ol_from_dict(ind, reps='DICTOBS'):
     obstypes = (Obs, Corr, np.ndarray)
 
     if not reps.isalnum():
-        raise Exception('Placeholder string has to be alphanumeric!')
+        raise ValueError('Placeholder string has to be alphanumeric!')
     ol = []
     counter = 0
 
@@ -588,7 +588,7 @@ def _ol_from_dict(ind, reps='DICTOBS'):
                 counter += 1
             elif isinstance(v, str):
                 if bool(re.match(rf'{reps}[0-9]+', v)):
-                    raise Exception(f'Dict contains string {v} that matches the placeholder! {reps} Cannot be safely exported.')
+                    raise ValueError(f'Dict contains string {v} that matches the placeholder! {reps} Cannot be safely exported.')
             x[k] = v
         return x
 
@@ -608,7 +608,7 @@ def _ol_from_dict(ind, reps='DICTOBS'):
                 counter += 1
             elif isinstance(e, str):
                 if bool(re.match(rf'{reps}[0-9]+', e)):
-                    raise Exception(f'Dict contains string {e} that matches the placeholder! {reps} Cannot be safely exported.')
+                    raise ValueError(f'Dict contains string {e} that matches the placeholder! {reps} Cannot be safely exported.')
             x.append(e)
         return x
 
@@ -655,7 +655,7 @@ def dump_dict_to_json(od, fname, description='', indent=1, reps='DICTOBS', gz=Tr
     """
 
     if not isinstance(od, dict):
-        raise Exception('od has to be a dictionary. Did you want to use dump_to_json?')
+        raise TypeError('od has to be a dictionary. Did you want to use dump_to_json?')
 
     infostring = ('This JSON file contains a python dictionary that has been parsed to a list of structures. '
                   'OBSDICT contains the dictionary, where Obs or other structures have been replaced by '
@@ -687,7 +687,7 @@ def _od_from_list_and_dict(ol, ind, reps='DICTOBS'):
         Specify the structure of the placeholder in imported dict to be reps[0-9]+.
     """
     if not reps.isalnum():
-        raise Exception('Placeholder string has to be alphanumeric!')
+        raise ValueError('Placeholder string has to be alphanumeric!')
 
     counter = 0
 
@@ -724,7 +724,7 @@ def _od_from_list_and_dict(ol, ind, reps='DICTOBS'):
     nd = dict_replace_string(ind)
 
     if counter == 0:
-        raise Exception('No placeholder has been replaced! Check if reps is set correctly.')
+        raise ValueError('No placeholder has been replaced! Check if reps is set correctly.')
 
     return nd
 
diff --git a/pyerrors/input/misc.py b/pyerrors/input/misc.py
index 179919c6..c7c7f5b2 100644
--- a/pyerrors/input/misc.py
+++ b/pyerrors/input/misc.py
@@ -121,7 +121,7 @@ def read_pbp(path, prefix, **kwargs):
         break
 
     if not ls:
-        raise Exception('Error, directory not found')
+        raise FileNotFoundError('Error, directory not found')
 
     # Exclude files with different names
     for exc in ls:
@@ -134,7 +134,7 @@ def read_pbp(path, prefix, **kwargs):
     if 'r_start' in kwargs:
         r_start = kwargs.get('r_start')
         if len(r_start) != replica:
-            raise Exception('r_start does not match number of replicas')
+            raise ValueError('r_start does not match number of replicas')
         # Adjust Configuration numbering to python index
         r_start = [o - 1 if o else None for o in r_start]
     else:
@@ -143,7 +143,7 @@ def read_pbp(path, prefix, **kwargs):
     if 'r_stop' in kwargs:
         r_stop = kwargs.get('r_stop')
         if len(r_stop) != replica:
-            raise Exception('r_stop does not match number of replicas')
+            raise ValueError('r_stop does not match number of replicas')
     else:
         r_stop = [None] * replica
 
diff --git a/pyerrors/input/openQCD.py b/pyerrors/input/openQCD.py
index a5297a57..6405a98f 100644
--- a/pyerrors/input/openQCD.py
+++ b/pyerrors/input/openQCD.py
@@ -49,7 +49,7 @@ def read_rwms(path, prefix, version='2.0', names=None, **kwargs):
     """
     known_oqcd_versions = ['1.4', '1.6', '2.0']
     if version not in known_oqcd_versions:
-        raise Exception('Unknown openQCD version defined!')
+        raise ValueError('Unknown openQCD version defined!')
     print("Working with openQCD version " + version)
     if 'postfix' in kwargs:
         postfix = kwargs.get('postfix')
@@ -68,7 +68,7 @@ def read_rwms(path, prefix, version='2.0', names=None, **kwargs):
     if 'r_start' in kwargs:
         r_start = kwargs.get('r_start')
         if len(r_start) != replica:
-            raise Exception('r_start does not match number of replicas')
+            raise ValueError('r_start does not match number of replicas')
         r_start = [o if o else None for o in r_start]
     else:
         r_start = [None] * replica
@@ -76,7 +76,7 @@ def read_rwms(path, prefix, version='2.0', names=None, **kwargs):
     if 'r_stop' in kwargs:
         r_stop = kwargs.get('r_stop')
         if len(r_stop) != replica:
-            raise Exception('r_stop does not match number of replicas')
+            raise ValueError('r_stop does not match number of replicas')
     else:
         r_stop = [None] * replica
 
@@ -301,7 +301,7 @@ def _extract_flowed_energy_density(path, prefix, dtr_read, xmin, spatial_extent,
     if 'r_start' in kwargs:
         r_start = kwargs.get('r_start')
         if len(r_start) != replica:
-            raise Exception('r_start does not match number of replicas')
+            raise ValueError('r_start does not match number of replicas')
         r_start = [o if o else None for o in r_start]
     else:
         r_start = [None] * replica
@@ -309,7 +309,7 @@ def _extract_flowed_energy_density(path, prefix, dtr_read, xmin, spatial_extent,
     if 'r_stop' in kwargs:
         r_stop = kwargs.get('r_stop')
         if len(r_stop) != replica:
-            raise Exception('r_stop does not match number of replicas')
+            raise ValueError('r_stop does not match number of replicas')
     else:
         r_stop = [None] * replica
 
@@ -641,7 +641,7 @@ def _find_files(path, prefix, postfix, ext, known_files=None):
             files.append(f)
 
     if files == []:
-        raise Exception("No files found after pattern filter!")
+        raise FileNotFoundError("No files found after pattern filter!")
 
     files = sort_names(files)
     return files
@@ -765,7 +765,7 @@ def read_gf_coupling(path, prefix, c, dtr_cnfg=1, Zeuthen_flow=True, **kwargs):
     """
 
     if c != 0.3:
-        raise Exception("The required lattice norm is only implemented for c=0.3 at the moment.")
+        raise NotImplementedError("The required lattice norm is only implemented for c=0.3 at the moment.")
 
     plaq = _read_flow_obs(path, prefix, c, dtr_cnfg=dtr_cnfg, version="sfqcd", obspos=6, sum_t=False, Zeuthen_flow=Zeuthen_flow, integer_charge=False, **kwargs)
     C2x1 = _read_flow_obs(path, prefix, c, dtr_cnfg=dtr_cnfg, version="sfqcd", obspos=7, sum_t=False, Zeuthen_flow=Zeuthen_flow, integer_charge=False, **kwargs)
@@ -773,10 +773,10 @@ def read_gf_coupling(path, prefix, c, dtr_cnfg=1, Zeuthen_flow=True, **kwargs):
     T = plaq.tag["T"]
 
     if T != L:
-        raise Exception("The required lattice norm is only implemented for T=L at the moment.")
+        raise NotImplementedError("The required lattice norm is only implemented for T=L at the moment.")
 
     if Zeuthen_flow is not True:
-        raise Exception("The required lattice norm is only implemented for the Zeuthen flow at the moment.")
+        raise NotImplementedError("The required lattice norm is only implemented for the Zeuthen flow at the moment.")
 
     t = (c * L) ** 2 / 8
 
@@ -854,7 +854,7 @@ def _read_flow_obs(path, prefix, c, dtr_cnfg=1, version="openQCD", obspos=0, sum
     known_versions = ["openQCD", "sfqcd"]
 
     if version not in known_versions:
-        raise Exception("Unknown openQCD version.")
+        raise ValueError("Unknown openQCD version.")
     if "steps" in kwargs:
         steps = kwargs.get("steps")
     if version == "sfqcd":
@@ -865,7 +865,7 @@ def _read_flow_obs(path, prefix, c, dtr_cnfg=1, version="openQCD", obspos=0, sum
         postfix = "gfms"
     else:
         if "L" not in kwargs:
-            raise Exception("This version of openQCD needs you to provide the spatial length of the lattice as parameter 'L'.")
+            raise ValueError("This version of openQCD needs you to provide the spatial length of the lattice as parameter 'L'.")
         else:
             L = kwargs.get("L")
         postfix = "ms"
@@ -883,7 +883,7 @@ def _read_flow_obs(path, prefix, c, dtr_cnfg=1, version="openQCD", obspos=0, sum
     if 'r_start' in kwargs:
         r_start = kwargs.get('r_start')
         if len(r_start) != len(files):
-            raise Exception('r_start does not match number of replicas')
+            raise ValueError('r_start does not match number of replicas')
         r_start = [o if o else None for o in r_start]
     else:
         r_start = [None] * len(files)
@@ -891,14 +891,14 @@ def _read_flow_obs(path, prefix, c, dtr_cnfg=1, version="openQCD", obspos=0, sum
     if 'r_stop' in kwargs:
         r_stop = kwargs.get('r_stop')
         if len(r_stop) != len(files):
-            raise Exception('r_stop does not match number of replicas')
+            raise ValueError('r_stop does not match number of replicas')
     else:
         r_stop = [None] * len(files)
     rep_names = []
 
     zeuthen = kwargs.get('Zeuthen_flow', False)
     if zeuthen and version not in ['sfqcd']:
-        raise Exception('Zeuthen flow can only be used for version==sfqcd')
+        raise ValueError('Zeuthen flow can only be used for version==sfqcd')
 
     r_start_index = []
     r_stop_index = []
@@ -1087,7 +1087,7 @@ def qtop_projection(qtop, target=0):
         projection to the topological charge sector defined by target
     """
     if qtop.reweighted:
-        raise Exception('You can not use a reweighted observable for reweighting!')
+        raise ValueError('You can not use a reweighted observable for reweighting!')
 
     proj_qtop = []
     for n in qtop.deltas:
@@ -1147,7 +1147,7 @@ def read_qtop_sector(path, prefix, c, target=0, **kwargs):
     """
 
     if not isinstance(target, int):
-        raise Exception("'target' has to be an integer.")
+        raise TypeError("'target' has to be an integer.")
 
     kwargs['integer_charge'] = True
     qtop = read_qtop(path, prefix, c, **kwargs)
@@ -1203,10 +1203,10 @@ def read_ms5_xsf(path, prefix, qc, corr, sep="r", **kwargs):
 
     # test if the input is correct
     if qc not in ['dd', 'ud', 'du', 'uu']:
-        raise Exception("Unknown quark conbination!")
+        raise ValueError("Unknown quark combination!")
 
     if corr not in ["gS", "gP", "gA", "gV", "gVt", "lA", "lV", "lVt", "lT", "lTt", "g1", "l1"]:
-        raise Exception("Unknown correlator!")
+        raise ValueError("Unknown correlator!")
 
     if "files" in kwargs:
         known_files = kwargs.get("files")
diff --git a/pyerrors/input/sfcf.py b/pyerrors/input/sfcf.py
index e164143c..1b4478ab 100644
--- a/pyerrors/input/sfcf.py
+++ b/pyerrors/input/sfcf.py
@@ -163,7 +163,7 @@ def read_sfcf_multi(path, prefix, name_list, quarks_list=None, corr_type_list=No
     known_versions = ["0.0", "1.0", "2.0", "1.0c", "2.0c", "1.0a", "2.0a"]
 
     if version not in known_versions:
-        raise Exception("This version is not known!")
+        raise ValueError("This version is not known!")
     if (version[-1] == "c"):
         appended = False
         compact = True
@@ -186,7 +186,7 @@ def read_sfcf_multi(path, prefix, name_list, quarks_list=None, corr_type_list=No
                 ls.extend(filenames)
             break
         if not ls:
-            raise Exception('Error, directory not found')
+            raise FileNotFoundError('Error, directory not found')
         # Exclude folders with different names
         for exc in ls:
             if not fnmatch.fnmatch(exc, prefix + '*'):
@@ -199,16 +199,16 @@ def read_sfcf_multi(path, prefix, name_list, quarks_list=None, corr_type_list=No
     else:
         replica = len([file.split(".")[-1] for file in ls]) // len(set([file.split(".")[-1] for file in ls]))
     if replica == 0:
-        raise Exception('No replica found in directory')
+        raise FileNotFoundError('No replica found in directory')
     if not silent:
         print('Read', part, 'part of', name_list, 'from', prefix[:-1], ',', replica, 'replica')
 
     if 'names' in kwargs:
         new_names = kwargs.get('names')
         if len(new_names) != len(set(new_names)):
-            raise Exception("names are not unique!")
+            raise ValueError("names are not unique!")
         if len(new_names) != replica:
-            raise Exception('names should have the length', replica)
+            raise ValueError(f'names should have the length {replica}')
 
     else:
         ens_name = kwargs.get("ens_name")
@@ -388,7 +388,7 @@ def read_sfcf_multi(path, prefix, name_list, quarks_list=None, corr_type_list=No
             print("Checking for missing configs...")
         che = kwargs.get("check_configs")
         if not (len(che) == len(idl)):
-            raise Exception("check_configs has to be the same length as replica!")
+            raise ValueError("check_configs has to be the same length as replica!")
         for r in range(len(idl)):
             if not silent:
                 print("checking " + new_names[r])
diff --git a/pyerrors/input/utils.py b/pyerrors/input/utils.py
index 37582ef7..1cd874b9 100644
--- a/pyerrors/input/utils.py
+++ b/pyerrors/input/utils.py
@@ -108,7 +108,7 @@ def check_params(path, param_hash, prefix, param_prefix="parameters_"):
         ls.extend(dirnames)
         break
     if not ls:
-        raise Exception('Error, directory not found')
+        raise FileNotFoundError('Error, directory not found')
     # Exclude folders with different names
     for exc in ls:
         if not fnmatch.fnmatch(exc, prefix + '*'):
diff --git a/pyerrors/linalg.py b/pyerrors/linalg.py
index 9ed9c763..9aaf7eea 100644
--- a/pyerrors/linalg.py
+++ b/pyerrors/linalg.py
@@ -203,7 +203,7 @@ def inv(x):
 def cholesky(x):
     """Cholesky decomposition of Obs valued matrices."""
     if any(isinstance(o, CObs) for o in x.ravel()):
-        raise Exception("Cholesky decomposition is not implemented for CObs.")
+        raise NotImplementedError("Cholesky decomposition is not implemented for CObs.")
     return _mat_mat_op(anp.linalg.cholesky, x)
 
 
diff --git a/pyerrors/misc.py b/pyerrors/misc.py
index 3f00cd10..c97781b2 100644
--- a/pyerrors/misc.py
+++ b/pyerrors/misc.py
@@ -160,7 +160,7 @@ def gen_correlated_data(means, cov, name, tau=0.5, samples=1000):
     assert len(means) == cov.shape[-1]
     tau = np.asarray(tau)
     if np.min(tau) < 0.5:
-        raise Exception('All integrated autocorrelations have to be >= 0.5.')
+        raise ValueError('All integrated autocorrelations have to be >= 0.5.')
 
     a = (2 * tau - 1) / (2 * tau + 1)
     rand = np.random.multivariate_normal(np.zeros_like(means), cov * samples, samples)  # noqa: NPY002
@@ -180,8 +180,8 @@ def _assert_equal_properties(ol, otype=Obs):
     otype = type(ol[0])
     for o in ol[1:]:
         if not isinstance(o, otype):
-            raise Exception("Wrong data type in list.")
+            raise TypeError("Wrong data type in list.")
         for attr in ["reweighted", "e_content", "idl"]:
             if hasattr(ol[0], attr):
                 if not getattr(ol[0], attr) == getattr(o, attr):
-                    raise Exception(f"All Obs in list have to have the same state '{attr}'.")
+                    raise ValueError(f"All Obs in list have to have the same state '{attr}'.")
diff --git a/pyerrors/mpm.py b/pyerrors/mpm.py
index ebbf32f8..96dde32b 100644
--- a/pyerrors/mpm.py
+++ b/pyerrors/mpm.py
@@ -35,7 +35,7 @@ def matrix_pencil_method(corrs, k=1, p=None, **kwargs):
 
     lengths = [len(d) for d in data]
     if lengths.count(lengths[0]) != len(lengths):
-        raise Exception('All datasets have to have the same length.')
+        raise ValueError('All datasets have to have the same length.')
 
     data_sets = len(data)
     n_data = len(data[0])
@@ -43,9 +43,9 @@ def matrix_pencil_method(corrs, k=1, p=None, **kwargs):
     if p is None:
         p = max(n_data // 2, k)
     if n_data <= p:
-        raise Exception('The pencil p has to be smaller than the number of data samples.')
+        raise ValueError('The pencil p has to be smaller than the number of data samples.')
     if p < k or n_data - p < k:
-        raise Exception('Cannot extract', k, 'energy levels with p=', p, 'and N-p=', n_data - p)
+        raise ValueError(f'Cannot extract {k} energy levels with p={p} and N-p={n_data - p}')
 
     # Construct the hankel matrices
     matrix = []
diff --git a/pyerrors/obs.py b/pyerrors/obs.py
index 3b4c3181..69a05bdf 100644
--- a/pyerrors/obs.py
+++ b/pyerrors/obs.py
@@ -1299,7 +1299,7 @@ def derived_observable(func, data, array_mode=False, **kwargs):
             raise ValueError('Manual derivative does not have correct shape.')
     elif kwargs.get('num_grad') is True:
         if multi > 0:
-            raise Exception('Multi mode currently not supported for numerical derivative')
+            raise NotImplementedError('Multi mode currently not supported for numerical derivative')
         options = {
             'base_step': 0.1,
             'step_ratio': 2.5}