diff --git a/poppy/accel_math.py b/poppy/accel_math.py
index 78346893..ff6d8ebf 100644
--- a/poppy/accel_math.py
+++ b/poppy/accel_math.py
@@ -221,7 +221,7 @@ def fft_2d(wavefront, forward=True, normalization=None, fftshift=True):
     _log.debug("using {2} FFT of {0} array, FFT_direction={1}".format(
         str(wavefront.shape), 'forward' if forward else 'backward', method))
 
-    if (forward) and fftshift: # shift before backwards propagations (using forward FFT)
+    if fftshift: # shift before backwards propagations (using forward FFT)
         # This needs to be an ifftshift, for machine-precision equivalence to MFT
         # as tested by test_MFT_FFT_equivalence_in_OpticalSystem; ifftshift and fftshift are
         # precisely equivalent for even-sized arrays but differ by 1 pixel offset for odd-sized
@@ -287,7 +287,7 @@ def fft_2d(wavefront, forward=True, normalization=None, fftshift=True):
         wavefront = do_fft(wavefront)
     t2 = time.time()
 
-    if (not forward) and fftshift:  # shift after forwards propagations (using inverse FFT)
+    if fftshift:  # shift after forwards propagations (using inverse FFT)
         # This needs to be a fftshift here, since we use ifftshift above
         # See comment above in this function.
         wavefront = _fftshift(wavefront)
diff --git a/poppy/tests/test_matrixDFT.py b/poppy/tests/test_matrixDFT.py
index db016d88..f1da3a82 100644
--- a/poppy/tests/test_matrixDFT.py
+++ b/poppy/tests/test_matrixDFT.py
@@ -695,5 +695,10 @@ def test_MFT_FFT_equivalence_in_OpticalSystem(tmpdir, display=False, source_offs
         poppy.display_psf_difference(fftpsf, mftpsf, title='Diff FFT-MFT')
 
 
+    # difference of intensities
     absdiff = np.abs(np.asarray(mftpsf[0].data - fftpsf[0].data))   # Extra asarray helps with optional GPU support
     assert(np.all(absdiff < 1e-10))
+
+    # absolute value of difference of complex fields
+    absdiff_c = np.abs(np.asarray(mftplanes[-1].wavefront - fftplanes[-1].wavefront))
+    assert(np.all(absdiff_c < 1e-10))