diff --git a/converters/NSLS2_HXN_hdf5_to_CXI.py b/converters/NSLS2_HXN_hdf5_to_CXI.py
new file mode 100755
index 0000000..3a345c5
--- /dev/null
+++ b/converters/NSLS2_HXN_hdf5_to_CXI.py
@@ -0,0 +1,130 @@
+#!/home/david/.conda/envs/CDToolsEnv/bin/python
+"""
+Purpose: Convert NSLSII HXN hdf5 files to CXI files for analysis with CDTools.
+Author:  David Rower
+Date:    December 2019
+"""
+
+import numpy as np
+import pickle
+import h5py
+import os
+import CDTools
+from CDTools.tools import data as cdtdata
+from matplotlib import pyplot as plt
+from scipy.spatial.transform import Rotation
+
+def create_cxi_from_NSLS2_HXN_2DFly(data_dir, save_str, scan_number,
+                                wavelength, theta, ROI_corner_xy):
+    """Converts NSLS2 HXN 2D Fly scan data (from pickle and hdf5) to CXI format
+
+    Assumes scan files will live in data_dir with naming convention
+    pickle: <data_dir>/scan_<scan_number>.pickle,
+    hdf5: <data_dir>/scan_<scan_number>.hdf5,
+    and will create the file <data_dir>/scan_<scan_number>.cxi.
+
+    Parameters
+    ----------
+    data_dir : str
+        Input data directory
+    save_str : str
+        Output data name
+    scan_number : int
+        A scan index number
+    theta : float
+        Rotation angle of sample in HXN convention, in degrees
+    ROI_corner_xy : np.array
+        1x2 array containing x, y corner of detector ROI
+    """
+
+    ## Load in pickle and hdf5 files
+    scan_str = "scan_" + scan_number
+    print('Scan #:', scan_number)
+
+    # Load pickle (includes useful data about scan not in .hdf5 file)
+    with open(os.path.join(data_dir, scan_str+".pickle"), 'rb') as f:
+        scan_pickle = pickle.load(f)
+
+    assert scan_pickle['plan_type'] == "FlyPlan2D", "Code only for FlyPlan2D."
+
+    # Load hdf5 file
+    scan_hdf5 = h5py.File(os.path.join(data_dir, scan_str+".h5"), 'r')
+
+
+    ## Let's attempt to convert this bad boy
+    print(80*'-'+'\nCreating cxi file.')
+
+
+    # We save as .h5 in order to inspect with panalopy GUI utility
+    scan_cxi = cdtdata.create_cxi(save_str)
+
+
+    ## Add source
+    cdtdata.add_source(scan_cxi, wavelength=wavelength)
+    scan_cxi['entry_1/instrument_1/source_1']['name'] = scan_pickle['beamline_id']
+
+
+    ## Add sample
+    theta = np.radians(theta)
+    sample_unit_vecs = Rotation.from_rotvec(theta * np.array([0,1,0])).as_dcm()
+    orientation = np.hstack((sample_unit_vecs[:,0], sample_unit_vecs[:,1]))
+    translation = np.zeros(3)
+    sample_info_dict = {
+        "name"        : "TaTe4",
+        "orientation" : orientation,
+        "translation" : translation
+    }
+    cdtdata.add_sample_info(scan_cxi, sample_info_dict)
+
+
+    ## Add detector
+
+    # Constant detector parameters
+    detector_pixel_size = 55e-6 # meters
+    detector_height_px = 515 # px ### WARNING: NEED TO CHECK THIS
+    detector_width_px = 515 # px
+
+    # Geometry parameters from scan files
+    distance = scan_pickle['dist_detector'] * 1e-3 # assuming mm, almost sure
+    gamma = np.radians(scan_pickle['gamma_detector'])
+    delta = np.radians(scan_pickle['delta_detector'])
+    Rg = Rotation.from_rotvec(-gamma * np.array([0,1,0])).as_dcm() # cw about y
+    Rd = Rotation.from_rotvec(-delta * Rg[:,0]).as_dcm() # cw about rotated x
+    RdRg = np.matmul(Rd, Rg)
+
+    # Define detector basis: row vectors for y and x detector axes
+    basis = detector_pixel_size * np.array([[0.,-1.,0.],[-1.,0.,0.]])
+    basis = np.matmul(RdRg,basis.T).T
+
+    # Define corner posiiton: first find center, then offset it
+    corner_pos = np.dot(RdRg, distance * np.array([0.,0.,1.]))
+    if ROI_corner_xy[0] is None:
+        ROI_corner_xy[0] = 0.
+    if ROI_corner_xy[1] is None:
+        ROI_corner_xy[1] = 0.
+    corner_pos -= basis[0,:] * (detector_width_px/2. - ROI_corner_xy[0])
+    corner_pos -= basis[1,:] * (detector_height_px/2. - ROI_corner_xy[1])
+
+    # Add detector data finally
+    cdtdata.add_detector(scan_cxi, distance, basis.T, corner=corner_pos)
+
+
+    ## Add data
+    axes = ['translation'] + scan_pickle['axes'] # THIS IS ONLY FOR FLY2D
+    data = np.copy(scan_hdf5['entry']['instrument']['detector']['data'])
+    data[data == 0] = 1 # to prevent divide by zero in log error
+    cdtdata.add_data(scan_cxi, data, axes)
+
+
+    ## Add translations
+    x_bounds = scan_pickle['scan_range'][0]
+    y_bounds = scan_pickle['scan_range'][1]
+    xx, yy = np.meshgrid(np.linspace(*x_bounds, scan_pickle['num1']),
+                               np.linspace(*y_bounds, scan_pickle['num2']))
+    translations = (1e-6 *
+        np.stack((xx.ravel(), yy.ravel(), np.zeros_like(xx.ravel())), axis=1))
+    cdtdata.add_ptycho_translations(scan_cxi, translations)
+
+
+    ## Close hdf5 file
+    scan_hdf5.close()