# How to cut out Target Pixel Files from Kepler Superstamps or TESS FFIs?¶

You can use lightkurve to cut Target Pixel Files (TPFs) out of a series of standard astronomical images, such as K2 Superstamp Mosaics or TESS Full-Frame-Images (FFIs). This brief tutorial will demonstrate how!

In [23]:

%matplotlib inline
from lightkurve import KeplerTargetPixelFile
from glob import glob
import numpy as np


Let’s assume you have downloaded a set simulated TESS FFI images to a local directory called data. lightkurve will assume that the files are given in time order. So we’ll sort the filenames first:

In [28]:

fnames = np.sort(glob('data/*.fits'))


Now we use the KeplerTargetPixelFile class and its function from_fits_images() to create the new TPF. This will cut out around the position keyword. You can pass a pixel position in units of the original image or RA and Dec coordinates.

In [29]:

tpf = KeplerTargetPixelFile.from_fits_images(images=fnames,
position=(197,210),
size=(5,5))

100%|██████████| 45/45 [00:01<00:00, 39.26it/s]

In [30]:

tpf.plot()

Out[30]:

<matplotlib.axes._subplots.AxesSubplot at 0x1c17d4dac8>

In [31]:

tpf.to_lightcurve().plot()

Out[31]:

<matplotlib.axes._subplots.AxesSubplot at 0x1c1b9f2d68>