diff --git a/src/scgenerator/__init__.py b/src/scgenerator/__init__.py
index aa16c7d..09e55d5 100644
--- a/src/scgenerator/__init__.py
+++ b/src/scgenerator/__init__.py
@@ -5,3 +5,4 @@ from .physics import fiber, materials, pulse, simulate, units
 from .physics.simulate import RK4IP, new_simulation, resume_simulations
 from .plotting import plot_avg, plot_results_1D, plot_results_2D, plot_spectrogram
 from .spectra import Pulse
+from . import utils
diff --git a/src/scgenerator/cli/cli.py b/src/scgenerator/cli/cli.py
index 7620af0..fa7c374 100644
--- a/src/scgenerator/cli/cli.py
+++ b/src/scgenerator/cli/cli.py
@@ -104,7 +104,7 @@ def create_parser():
     init_plot_parser.add_argument("config", help="path to the config file")
     init_plot_parser.add_argument(
         "--dispersion-limits",
-        "-s",
+        "-d",
         default=None,
         type=float,
         nargs=2,
diff --git a/src/scgenerator/defaults.py b/src/scgenerator/defaults.py
index 27c9eb2..60d840a 100644
--- a/src/scgenerator/defaults.py
+++ b/src/scgenerator/defaults.py
@@ -23,7 +23,7 @@ default_parameters = dict(
     parallel=True,
     repeat=1,
     tolerated_error=1e-11,
-    lower_wavelength_interp_limit=300e-9,
+    lower_wavelength_interp_limit=100e-9,
     upper_wavelength_interp_limit=1900e-9,
     interp_degree=8,
     ideal_gas=False,
diff --git a/src/scgenerator/initialize.py b/src/scgenerator/initialize.py
index 3426d2f..ebefae7 100644
--- a/src/scgenerator/initialize.py
+++ b/src/scgenerator/initialize.py
@@ -85,8 +85,8 @@ class Params(BareParams):
         logger = get_logger(__name__)
 
         self.interp_range = (
-            max(self.lower_wavelength_interp_limit, units.m.inv(np.max(self.w[self.w > 0]))),
-            min(self.upper_wavelength_interp_limit, units.m.inv(np.min(self.w[self.w > 0]))),
+            max(self.lower_wavelength_interp_limit, self.l[self.l > 0].min()),
+            min(self.upper_wavelength_interp_limit, self.l[self.l > 0].max()),
         )
 
         temp_gamma = None
@@ -106,7 +106,7 @@ class Params(BareParams):
 
         if self.gamma is None:
             self.gamma = temp_gamma
-            logger.info(f"using computed \u0263 = {self.gamma:.2e} W/m^2")
+            logger.info(f"using computed \u0263 = {self.gamma:.2e} W/m\u00B2")
 
         # Raman response
         if "raman" in self.behaviors:
diff --git a/src/scgenerator/logger.py b/src/scgenerator/logger.py
index c669740..1bea9f1 100644
--- a/src/scgenerator/logger.py
+++ b/src/scgenerator/logger.py
@@ -63,6 +63,6 @@ def configure_logger(logger: logging.Logger):
             stream_handler.setLevel(print_lvl)
             logger.addHandler(stream_handler)
 
-        logger.setLevel(min(print_lvl, file_lvl))
+        logger.setLevel(logging.DEBUG)
         logger.already_configured = True
     return logger
diff --git a/src/scgenerator/physics/fiber.py b/src/scgenerator/physics/fiber.py
index be4144f..1e139c5 100644
--- a/src/scgenerator/physics/fiber.py
+++ b/src/scgenerator/physics/fiber.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, List, Literal, Tuple
+from typing import Any, Dict, Iterable, List, Literal, Tuple, Union
 
 import numpy as np
 import toml
@@ -6,6 +6,8 @@ from numpy.fft import fft, ifft
 from numpy.polynomial.chebyshev import Chebyshev, cheb2poly
 from scipy.interpolate import interp1d
 
+from ..logger import get_logger
+
 from .. import io
 from ..math import abs2, argclosest, power_fact, u_nm
 from ..utils.parameter import BareParams, hc_model_specific_parameters
@@ -15,14 +17,14 @@ from . import units
 from .units import c, pi
 
 
-def lambda_for_dispersion():
+def lambda_for_dispersion(left: float, right: float) -> np.ndarray:
     """Returns a wl vector for dispersion calculation
 
     Returns
     -------
     array of wl values
     """
-    return np.linspace(190e-9, 3000e-9, 4000)
+    return np.arange(left - 2e-9, right + 3e-9, 1e-9)
 
 
 def is_dynamic_dispersion(pressure=None):
@@ -679,7 +681,7 @@ def compute_dispersion(params: BareParams):
         gamma = None
     else:
         interp_range = params.interp_range
-        lambda_ = lambda_for_dispersion()
+        lambda_ = lambda_for_dispersion(*interp_range)
         beta2 = np.zeros_like(lambda_)
 
         if params.model == "pcf":
@@ -773,7 +775,7 @@ def dispersion_coefficients(
         beta2_coef : 1D array
             Taylor coefficients in decreasing order
     """
-
+    logger = get_logger()
     if interp_range is None:
         r = slice(2, -2)
     else:
@@ -783,15 +785,50 @@ def dispersion_coefficients(
         r = (lambda_ > max(lambda_[2], interp_range[0])) & (
             lambda_ < min(lambda_[-2], interp_range[1])
         )
+    logger.debug(
+        f"interpolating dispersion between {lambda_[r].min()*1e9:.1f}nm and {lambda_[r].max()*1e9:.1f}nm"
+    )
+    # import matplotlib.pyplot as plt
 
     # we get the beta2 Taylor coeffiecients by making a fit around w0
     w_c = units.m(lambda_) - w0
+    # interp = interp1d(w_c[r], beta2[r])
+    # w_c = np.linspace(w_c)
+    # fig, ax = plt.subplots()
+    # ax.plot(w_c[r], beta2[r])
+    # fig.show()
+
     fit = Chebyshev.fit(w_c[r], beta2[r], deg)
     beta2_coef = cheb2poly(fit.convert().coef) * np.cumprod([1] + list(range(1, deg + 1)))
 
     return beta2_coef
 
 
+def dispersion_from_coefficients(
+    w_c: np.ndarray, beta: Union[list[float], np.ndarray]
+) -> np.ndarray:
+    """computes the dispersion profile (beta2) from the beta coefficients
+
+    Parameters
+    ----------
+    w_c : np.ndarray, shape (n, )
+        centered angular frequency (0 <=> pump frequency)
+    beta : Iterable[float]
+        beta coefficients
+
+    Returns
+    -------
+    np.ndarray, shape (n, )
+        beta2 as function of w_c
+    """
+
+    coef = np.array(beta) / np.cumprod([1] + list(range(1, len(beta))))
+    beta_arr = np.zeros_like(w_c)
+    for k, b in reversed(list(enumerate(coef))):
+        beta_arr = beta_arr + b * w_c ** k
+    return beta_arr
+
+
 def delayed_raman_t(t, raman_type="stolen"):
     """
     computes the unnormalized temporal Raman response function applied to the array t
@@ -1007,3 +1044,16 @@ def effective_core_radius(lambda_, core_radius, s=0.08, h=200e-9):
 def effective_radius_HCARF(core_radius, t, f1, f2, lambda_):
     """eq. 3 in Hasan 2018"""
     return f1 * core_radius * (1 - f2 * lambda_ ** 2 / (core_radius * t))
+
+
+if __name__ == "__main__":
+    w = np.linspace(0, 1, 4096)
+    c = np.arange(8)
+    import time
+
+    t = time.time()
+
+    for _ in range(10000):
+        dispersion_from_coefficients(w, c)
+
+    print((time.time() - t) / 10, "ms")
diff --git a/src/scgenerator/physics/pulse.py b/src/scgenerator/physics/pulse.py
index ddff8c6..a40152f 100644
--- a/src/scgenerator/physics/pulse.py
+++ b/src/scgenerator/physics/pulse.py
@@ -12,13 +12,16 @@ n is the number of spectra at the same z position and nt is the size of the time
 import itertools
 import os
 from pathlib import Path
-from typing import Literal, Tuple
+from typing import Literal, Tuple, TypeVar
 
 import matplotlib.pyplot as plt
 import numpy as np
 from numpy import pi
 from numpy.fft import fft, fftshift, ifft
+from scipy import optimize
 from scipy.interpolate import UnivariateSpline
+from scipy.optimize import minimize_scalar
+from scipy.optimize.optimize import OptimizeResult
 
 from .. import io
 from ..defaults import default_plotting
@@ -30,7 +33,7 @@ from . import units
 
 c = 299792458.0
 hbar = 1.05457148e-34
-
+T = TypeVar("T")
 
 #
 fwhm_to_T0_fac = dict(
@@ -535,14 +538,23 @@ def peak_ind(values, mam=None):
         am = np.argmax(values)
     else:
         m, am = mam
-    left_ind = (
-        am
-        - np.where((values[am:0:-1] - values[am - 1 :: -1] < 0) & (values[am:0:-1] < m / 2))[0][0]
-    )
-    right_ind = (
-        am + np.where((values[am:-1] - values[am + 1 :] < 0) & (values[am:-1] < m / 2))[0][0]
-    )
-    return left_ind - 3, right_ind + 3
+
+    try:
+        left_ind = (
+            am
+            - np.where((values[am:0:-1] - values[am - 1 :: -1] <= 0) & (values[am:0:-1] < m / 2))[
+                0
+            ][0]
+        ) - 3
+    except IndexError:
+        left_ind = 0
+    try:
+        right_ind = (
+            am + np.where((values[am:-1] - values[am + 1 :] <= 0) & (values[am:-1] < m / 2))[0][0]
+        ) + 3
+    except IndexError:
+        right_ind = len(values) - 1
+    return left_ind, right_ind
 
 
 def setup_splines(x_axis, values, mam=None):
@@ -895,3 +907,32 @@ def measure_field(t: np.ndarray, field: np.ndarray) -> Tuple[float, float, float
     peak_power = intensity.max()
     energy = np.trapz(intensity, t)
     return fwhm, peak_power, energy
+
+
+def remove_2nd_order_dispersion(
+    spectrum: T, w_c: np.ndarray, beta2: float, max_z: float = -1.0
+) -> tuple[T, OptimizeResult]:
+    """attempts to remove 2nd order dispersion from a complex spectrum
+
+    Parameters
+    ----------
+    spectrum : np.ndarray or Spectrum, shape (n, )
+        spectrum from which to remove 2nd order dispersion
+    w_c : np.ndarray, shape (n, )
+        corresponding centered angular frequencies (w-w0)
+    beta2 : float
+        2nd order dispersion coefficient
+
+    Returns
+    -------
+    np.ndarray, shape (n, )
+        spectrum with 2nd order dispersion removed
+    """
+    # makeshift_t = np.linspace(0, 1, len(w_c))
+    propagate = lambda z: spectrum * np.exp(-0.5j * beta2 * w_c ** 2 * z)
+
+    def score(z):
+        return 1 / np.max(abs2(np.fft.ifft(propagate(z))))
+
+    opti = minimize_scalar(score, bracket=(max_z, 0))
+    return propagate(opti.x), opti
diff --git a/src/scgenerator/physics/units.py b/src/scgenerator/physics/units.py
index 668b8a5..a2514d8 100644
--- a/src/scgenerator/physics/units.py
+++ b/src/scgenerator/physics/units.py
@@ -6,6 +6,9 @@ import re
 from threading import settrace
 from typing import Callable, TypeVar, Union
 from dataclasses import dataclass
+from matplotlib import pyplot as plt
+
+from numpy.lib.arraysetops import isin
 from ..utils.parameter import Parameter, type_checker
 import numpy as np
 from numpy import pi
@@ -255,7 +258,8 @@ def sort_axis(axis, plt_range: PlotRange):
     # slice y according to the given ranges
     y = y[ct][:, cw]
     """
-
+    if isinstance(plt_range, tuple):
+        plt_range = PlotRange(*plt_range)
     r = np.array((plt_range.left, plt_range.right), dtype="float")
 
     indices = np.arange(len(axis))[
diff --git a/src/scgenerator/plotting.py b/src/scgenerator/plotting.py
index 62d915c..0f5b03c 100644
--- a/src/scgenerator/plotting.py
+++ b/src/scgenerator/plotting.py
@@ -30,7 +30,7 @@ def plot_setup(
     - an axis
     """
     out_path = defaults["name"] if out_path is None else out_path
-    plot_name = out_path.stem
+    plot_name = out_path.name.replace(f".{file_type}", "")
     out_dir = out_path.resolve().parent
 
     file_name = plot_name + "." + file_type
@@ -286,9 +286,8 @@ def _finish_plot_2D(
     if isinstance(ax, tuple) and len(ax) > 1:
         ax, cbar_ax = ax[0], ax[1]
 
-    folder_name = ""
     if is_new_plot:
-        out_path, fig, ax = plot_setup(out_path=Path(folder_name) / file_name, file_type=file_type)
+        out_path, fig, ax = plot_setup(out_path=Path(file_name), file_type=file_type)
     else:
         fig = ax.get_figure()
 
diff --git a/src/scgenerator/scripts/__init__.py b/src/scgenerator/scripts/__init__.py
index d37775e..18e3c81 100644
--- a/src/scgenerator/scripts/__init__.py
+++ b/src/scgenerator/scripts/__init__.py
@@ -1,7 +1,7 @@
 from itertools import cycle
 import itertools
 from pathlib import Path
-from typing import Iterable
+from typing import Any, Iterable, Optional
 from cycler import cycler
 
 import matplotlib.pyplot as plt
@@ -12,10 +12,16 @@ from ..utils.parameter import BareParams
 from ..initialize import ParamSequence
 from ..physics import units, fiber
 from ..spectra import Pulse
-from ..utils import pretty_format_value
+from ..utils import pretty_format_value, pretty_format_from_file_name, auto_crop
 from .. import env, math
 
 
+def fingerprint(params: BareParams):
+    h1 = hash(params.field_0.tobytes())
+    h2 = tuple(params.beta)
+    return h1, h2
+
+
 def plot_all(sim_dir: Path, limits: list[str]):
     for p in sim_dir.glob("*"):
         if not p.is_dir():
@@ -26,7 +32,13 @@ def plot_all(sim_dir: Path, limits: list[str]):
             left, right, unit = lim.split(",")
             left = float(left)
             right = float(right)
-            pulse.plot_2D(left, right, unit, file_name=p.parent / f"{p.name}_{left}_{right}_{unit}")
+            pulse.plot_2D(
+                left,
+                right,
+                unit,
+                file_name=p.parent
+                / f"{pretty_format_from_file_name(p.name)} {left} {right} {unit}",
+            )
 
 
 def plot_init_field_spec(
@@ -49,7 +61,7 @@ def plot_init_field_spec(
 
 
 def plot_dispersion(config_path: Path, lim: tuple[float, float] = None):
-    fig, (left, right) = plt.subplots(1, 2, figsize=(12, 7), sharex=True)
+    fig, (left, right) = plt.subplots(1, 2, figsize=(12, 7))
     left.grid()
     right.grid()
     all_labels = []
@@ -62,7 +74,7 @@ def plot_dispersion(config_path: Path, lim: tuple[float, float] = None):
 
         lbl = plot_1_dispersion(lim, left, right, style, lbl, params)
         all_labels.append(lbl)
-    finish_plot(fig, left, right, all_labels, params)
+    finish_plot(fig, right, all_labels, params)
 
 
 def plot_init(
@@ -77,8 +89,8 @@ def plot_init(
     all_labels = []
     already_plotted = set()
     for style, lbl, params in plot_helper(config_path):
-        if (bbb := hash(params.field_0.tobytes())) not in already_plotted:
-            already_plotted.add(bbb)
+        if (fp := fingerprint(params)) not in already_plotted:
+            already_plotted.add(fp)
         else:
             continue
         lbl = plot_1_dispersion(lim_disp, tl, tr, style, lbl, params)
@@ -90,8 +102,8 @@ def plot_init(
 def plot_1_init_spec_field(lim_t, lim_l, left, right, style, lbl, params):
     field = math.abs2(params.field_0)
     spec = math.abs2(params.spec_0)
-    t = units.fs.inv(params.t)
-    wl = units.nm.inv(params.w)
+    t = units.To.fs(params.t)
+    wl = units.To.nm(params.w)
 
     lbl.append(f"max at {wl[spec.argmax()]:.1f} nm")
 
@@ -100,54 +112,68 @@ def plot_1_init_spec_field(lim_t, lim_l, left, right, style, lbl, params):
         mt &= t >= lim_t[0]
         mt &= t <= lim_t[1]
     else:
-        mt = find_lim(t, field)
+        mt = auto_crop(t, field)
     ml = np.ones_like(wl, dtype=bool)
     if lim_l is not None:
-        ml &= t >= lim_l[0]
-        ml &= t <= lim_l[1]
+        ml &= wl >= lim_l[0]
+        ml &= wl <= lim_l[1]
     else:
-        ml = find_lim(wl, spec)
+        ml = auto_crop(wl, spec)
 
     left.plot(t[mt], field[mt])
     right.plot(wl[ml], spec[ml], label=" ", **style)
     return lbl
 
 
-def plot_1_dispersion(lim, left, right, style, lbl, params):
-    coef = params.beta / np.cumprod([1] + list(range(1, len(params.beta))))
-    w_c = params.w_c
-
-    beta_arr = np.zeros_like(w_c)
-    for k, beta in reversed(list(enumerate(coef))):
-        beta_arr = beta_arr + beta * w_c ** k
+def plot_1_dispersion(
+    lim: Optional[tuple[float, float]],
+    left: plt.Axes,
+    right: plt.Axes,
+    style: dict[str, Any],
+    lbl: list[str],
+    params: BareParams,
+):
+    beta_arr = fiber.dispersion_from_coefficients(params.w_c, params.beta)
     wl = units.m.inv(params.w)
+    D = fiber.beta2_to_D(beta_arr, wl) * 1e6
 
     zdw = math.all_zeros(wl, beta_arr)
     if len(zdw) > 0:
         zdw = zdw[np.argmin(abs(zdw - params.wavelength))]
-        lbl.append(f"ZDW at {zdw*1e9:.1f}nm")
+        lbl.append(f"ZDW at {zdw:.1f}nm")
     else:
         lbl.append("")
 
     m = np.ones_like(wl, dtype=bool)
     if lim is None:
         lim = params.interp_range
-    m &= wl >= lim[0]
-    m &= wl <= lim[1]
+    m &= wl >= (lim[0] if lim[0] < 1 else lim[0] * 1e-9)
+    m &= wl <= (lim[1] if lim[1] < 1 else lim[1] * 1e-9)
+
+    left.annotate(
+        rf"$\lambda_{{\mathrm{{min}}}}={np.min(params.l[params.l>0])*1e9:.1f}$ nm"
+        f"lower interpolation limit : {params.interp_range[0]*1e9:.1f} nm",
+        (0, 1),
+        xycoords="axes fraction",
+        va="top",
+        ha="left",
+    )
 
     m = np.argwhere(m)[:, 0]
     m = np.array(sorted(m, key=lambda el: wl[el]))
 
+    if len(m) == 0:
+        raise ValueError(f"nothing to plot in the range {lim!r}")
+
     # plot D
-    D = fiber.beta2_to_D(beta_arr, wl) * 1e6
     right.plot(1e9 * wl[m], D[m], label=" ", **style)
     right.set_ylabel(units.D_ps_nm_km.label)
 
     # plot beta
-    left.plot(1e9 * wl[m], units.beta2_fs_cm.inv(beta_arr[m]), label=" ", **style)
+    left.plot(units.To.Prad_s(params.w[m]), units.beta2_fs_cm.inv(beta_arr[m]), label=" ", **style)
     left.set_ylabel(units.beta2_fs_cm.label)
 
-    left.set_xlabel("wavelength (nm)")
+    left.set_xlabel(units.Prad_s.label)
     right.set_xlabel("wavelength (nm)")
     return lbl
 
@@ -188,21 +214,3 @@ def plot_helper(config_path: Path) -> Iterable[tuple[dict, list[str], BareParams
     for style, (variables, params) in zip(cc, pseq):
         lbl = [pretty_format_value(name, value) for name, value in variables[1:-1]]
         yield style, lbl, params
-
-
-def find_lim(x: np.ndarray, y: np.ndarray, rel_thr: float = 0.01) -> int:
-    threshold = y.min() + rel_thr * (y.max() - y.min())
-    above_threshold = y > threshold
-    ind = np.argsort(x)
-    valid_ind = [
-        np.array(list(g)) for k, g in itertools.groupby(ind, key=lambda i: above_threshold[i]) if k
-    ]
-    ind_above = sorted(valid_ind, key=lambda el: len(el), reverse=True)[0]
-    width = len(ind_above)
-    return np.concatenate(
-        (
-            np.arange(max(ind_above[0] - width, 0), ind_above[0]),
-            ind_above,
-            np.arange(ind_above[-1] + 1, min(len(y), ind_above[-1] + width)),
-        )
-    )
diff --git a/src/scgenerator/spectra.py b/src/scgenerator/spectra.py
index ed85382..54f173f 100644
--- a/src/scgenerator/spectra.py
+++ b/src/scgenerator/spectra.py
@@ -47,7 +47,7 @@ class Spectrum(np.ndarray):
         else:
             return np.array([s.energy() for s in self])
 
-    def crop_wl(self, left: float, right: float) -> tuple[np.ndarray, np.ndarray]:
+    def crop_wl(self, left: float, right: float) -> np.ndarray:
         cond = (self.params.l >= left) & (self.params.l <= right)
         return cond
 
@@ -120,6 +120,9 @@ class Spectrum(np.ndarray):
             -(((self.params.l - pos) / (pulse.fwhm_to_T0_fac["gaussian"] * width)) ** 2)
         )
 
+    def measure(self) -> tuple[float, float, float]:
+        return pulse.measure_field(self.params.t, self.time_amp)
+
 
 class Pulse(Sequence):
     def __init__(self, path: os.PathLike, default_ind: Union[int, Iterable[int]] = None):
@@ -180,7 +183,7 @@ class Pulse(Sequence):
     def __len__(self):
         return self.nmax
 
-    def __getitem__(self, key):
+    def __getitem__(self, key) -> Spectrum:
         return self.all_spectra(ind=range(self.nmax)[key]).squeeze()
 
     def intensity(self, unit):
@@ -282,6 +285,7 @@ class Pulse(Sequence):
         spectra = []
         for i in ind:
             spectra.append(self._load1(i))
+        spectra = Spectrum(spectra, self.params)
 
         self.logger.debug(f"all spectra from {self.path} successfully loaded")
         if len(ind) == 1:
diff --git a/src/scgenerator/utils/__init__.py b/src/scgenerator/utils/__init__.py
index 2fb428b..a924156 100644
--- a/src/scgenerator/utils/__init__.py
+++ b/src/scgenerator/utils/__init__.py
@@ -4,6 +4,7 @@ scgenerator module but some function may be used in any python program
 
 """
 
+from argparse import ArgumentTypeError
 import itertools
 import multiprocessing
 import re
@@ -214,6 +215,17 @@ def pretty_format_value(name: str, value) -> str:
     return getattr(BareParams, name).display(value)
 
 
+def pretty_format_from_file_name(name: str) -> str:
+    s = name.split(PARAM_SEPARATOR)
+    out = []
+    for key, value in zip(s[::2], s[1::2]):
+        try:
+            out.append(getattr(BareParams, key).display(float(value)))
+        except (AttributeError, ValueError):
+            out.append(key + PARAM_SEPARATOR + value)
+    return PARAM_SEPARATOR.join(out)
+
+
 def variable_iterator(config: BareConfig) -> Iterator[Tuple[List[Tuple[str, Any]], BareParams]]:
     """given a config with "variable" parameters, iterates through every possible combination,
     yielding a a list of (parameter_name, value) tuples and a full config dictionary.
@@ -282,3 +294,21 @@ def override_config(new: Dict[str, Any], old: BareConfig = None) -> BareConfig:
     for k in new:
         variable.pop(k, None)  # remove old ones
     return replace(old, variable=variable, **{k: None for k in variable}, **new)
+
+
+def auto_crop(x: np.ndarray, y: np.ndarray, rel_thr: float = 0.01) -> np.ndarray:
+    threshold = y.min() + rel_thr * (y.max() - y.min())
+    above_threshold = y > threshold
+    ind = np.argsort(x)
+    valid_ind = [
+        np.array(list(g)) for k, g in itertools.groupby(ind, key=lambda i: above_threshold[i]) if k
+    ]
+    ind_above = sorted(valid_ind, key=lambda el: len(el), reverse=True)[0]
+    width = len(ind_above)
+    return np.concatenate(
+        (
+            np.arange(max(ind_above[0] - width, 0), ind_above[0]),
+            ind_above,
+            np.arange(ind_above[-1] + 1, min(len(y), ind_above[-1] + width)),
+        )
+    )
diff --git a/src/scgenerator/utils/parameter.py b/src/scgenerator/utils/parameter.py
index 1b2ac0d..f36646d 100644
--- a/src/scgenerator/utils/parameter.py
+++ b/src/scgenerator/utils/parameter.py
@@ -421,7 +421,7 @@ class BareParams:
         dico : dict
             dictionary
         """
-        forbiden_keys = ["w_c", "w_power_fact", "field_0", "spec_0", "w", "t", "z_targets"]
+        forbiden_keys = ["w_c", "w_power_fact", "field_0", "spec_0", "w", "t", "z_targets", "l"]
         types = (np.ndarray, float, int, str, list, tuple, dict)
         out = {}
         for key, value in dico.items():