diff --git a/esbo_etc/classes/target/ATarget.py b/esbo_etc/classes/target/ATarget.py
index 73f0191..21359a0 100644
--- a/esbo_etc/classes/target/ATarget.py
+++ b/esbo_etc/classes/target/ATarget.py
@@ -11,7 +11,8 @@ class ATarget(IRadiant):
     """
 
     @abstractmethod
-    def __init__(self, sfd: SpectralQty):
+    @u.quantity_input(wl_bins="length")
+    def __init__(self, sfd: SpectralQty, wl_bins: u.Quantity):
         """
         Initialize a new target
 
@@ -21,6 +22,7 @@ class ATarget(IRadiant):
             The spectral flux density of the target
         """
         self.__sfd = sfd
+        self.__wl_bins = wl_bins
 
     def calcNoise(self) -> SpectralQty:
         """
@@ -31,7 +33,7 @@ class ATarget(IRadiant):
         noise : SpectralQty
             The spectral radiance of the target's noise
         """
-        return SpectralQty(self.__sfd.wl, np.repeat(0, len(self.__sfd.wl)) << u.W / (u.m**2 * u.nm * u.sr))
+        return SpectralQty(self.__wl_bins, np.repeat(0, len(self.__wl_bins)) << u.W / (u.m**2 * u.nm * u.sr))
 
     def calcSignal(self) -> SpectralQty:
         """
diff --git a/esbo_etc/classes/target/BlackBodyTarget.py b/esbo_etc/classes/target/BlackBodyTarget.py
index 5105712..43721a7 100644
--- a/esbo_etc/classes/target/BlackBodyTarget.py
+++ b/esbo_etc/classes/target/BlackBodyTarget.py
@@ -53,4 +53,4 @@ class BlackBodyTarget(ATarget):
         sfd = bb(wl_bins) * factor * 10 ** (- 2 / 5 * mag / u.mag)
 
         # Initialize super class
-        super().__init__(SpectralQty(wl_bins, sfd))
+        super().__init__(SpectralQty(wl_bins, sfd), wl_bins)
diff --git a/esbo_etc/classes/target/FileTarget.py b/esbo_etc/classes/target/FileTarget.py
index 872eeda..3d4c00f 100644
--- a/esbo_etc/classes/target/FileTarget.py
+++ b/esbo_etc/classes/target/FileTarget.py
@@ -8,7 +8,8 @@ class FileTarget(ATarget):
     A class to create a target from a file containing the spectral flux densities
     """
 
-    def __init__(self, file: str):
+    @u.quantity_input(wl_bins="length")
+    def __init__(self, file: str, wl_bins: u.Quantity):
         """
         Initialize a new target from a file containing the spectral flux density values
 
@@ -19,8 +20,10 @@ class FileTarget(ATarget):
             and the corresponding spectral flux density. The format of the file will be guessed by
             `astropy.io.ascii.read(). If the file doesn't provide units via astropy's enhanced CSV format, the units
             will be read from the column headers or otherwise assumed to be *nm* and *W / m^2 / nm*.
+        wl_bins : length-Quantity
+            Wavelengths used for binning
         """
         # Create spectral quantity from file
         sfd = SpectralQty.fromFile(file, u.nm, u.W / (u.m ** 2 * u.nm))
         # Initialize the super class
-        super().__init__(sfd)
+        super().__init__(sfd, wl_bins)
diff --git a/tests/target/test_FileTarget.py b/tests/target/test_FileTarget.py
index 35baf78..ec174db 100644
--- a/tests/target/test_FileTarget.py
+++ b/tests/target/test_FileTarget.py
@@ -7,7 +7,7 @@ import numpy as np
 
 class TestFileTarget(TestCase):
     def setUp(self):
-        self.target = FileTarget("../data/target/target_demo_1.csv")
+        self.target = FileTarget("../data/target/target_demo_1.csv", np.arange(200, 210, 1) << u.nm)
 
     def test_signal(self):
         signal = SpectralQty(np.arange(200, 210, 1) << u.nm,