<div dir="ltr"><div>Hi. <br></div><div><br></div><div>I am trying to align two images I downloaded from MAST HST portal. For this, I am using astropy-reproject package. However, I am running into an error, every time I use reproject, despite providing the WCS information. <br></div><div> Following is the error: <br></div><div><pre style="box-sizing:border-box;overflow:auto;font-family:monospace;font-size:14px;display:block;padding:1px 0px;margin:0px;line-height:inherit;color:rgb(0,0,0);word-break:break-all;background-color:rgb(255,255,255);border:0px none;border-radius:0px;white-space:pre-wrap;vertical-align:baseline;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial"><span class="gmail-ansi-red-fg" style="box-sizing:border-box;color:rgb(231,92,88)">ValueError</span>: an astropy.io.fits.HDUList is required for Lookup table distortion.<br></pre><pre style="box-sizing:border-box;overflow:auto;font-family:monospace;font-size:14px;display:block;padding:1px 0px;margin:0px;line-height:inherit;color:rgb(0,0,0);word-break:break-all;background-color:rgb(255,255,255);border:0px none;border-radius:0px;white-space:pre-wrap;vertical-align:baseline;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial"><font face="times new roman,serif">I am using reproject version 0.6, and astropy both versions (3.2.3 and 4.0).<br></font></pre><pre style="box-sizing:border-box;overflow:auto;font-family:monospace;font-size:14px;display:block;padding:1px 0px;margin:0px;line-height:inherit;color:rgb(0,0,0);word-break:break-all;background-color:rgb(255,255,255);border:0px none;border-radius:0px;white-space:pre-wrap;vertical-align:baseline;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial"><font face="times new roman,serif">Information about the images: One image is from HST/WFC3 and second one is from HST/ACS.   I am attaching the two images along with my reproject code (.ipynb). Please let me know how to proceed and solve this issue. Thanks in advance. <br></font></pre><pre style="box-sizing:border-box;overflow:auto;font-family:monospace;font-size:14px;display:block;padding:1px 0px;margin:0px;line-height:inherit;color:rgb(0,0,0);word-break:break-all;background-color:rgb(255,255,255);border:0px none;border-radius:0px;white-space:pre-wrap;vertical-align:baseline;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial"><font face="times new roman,serif"></font></pre><div class="gmail_chip gmail_drive_chip" style="width:396px;height:18px;max-height:18px;background-color:rgb(245,245,245);padding:5px;color:rgb(34,34,34);font-family:arial;font-style:normal;font-weight:bold;font-size:13px;border:1px solid rgb(221,221,221);line-height:1"><a href="https://drive.google.com/a/students.mq.edu.au/file/d/1815Npx--OXYrDlN1zrgyVzpN5fwuGa3B/view?usp=drive_web" target="_blank" style="display:inline-block;max-width:366px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration:none;padding:1px 0;border:none"><img style="vertical-align: bottom; border: none;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="color:rgb(17,85,204);text-decoration:none;vertical-align:bottom">astropy_reproject_NGC_2257.ipynb</span></a><img src="//ssl.gstatic.com/ui/v1/icons/common/x_8px.png" style="opacity: 0.55; cursor: pointer; float: right; position: relative; top: -1px; display: none;"></div><div class="gmail_chip gmail_drive_chip" style="width:396px;height:18px;max-height:18px;background-color:rgb(245,245,245);padding:5px;color:rgb(34,34,34);font-family:arial;font-style:normal;font-weight:bold;font-size:13px;border:1px solid rgb(221,221,221);line-height:1"><a href="https://drive.google.com/a/students.mq.edu.au/file/d/1u3RFtGVDJa3cj6vEjvUcocJxWykEA4Z4/view?usp=drive_web" target="_blank" style="display:inline-block;max-width:366px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration:none;padding:1px 0;border:none"><img style="vertical-align: bottom; border: none;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="color:rgb(17,85,204);text-decoration:none;vertical-align:bottom">f336w_01_flt.fits</span></a><img src="//ssl.gstatic.com/ui/v1/icons/common/x_8px.png" style="opacity: 0.55; cursor: pointer; float: right; position: relative; top: -1px; display: none;"></div><div class="gmail_chip gmail_drive_chip" style="width:396px;height:18px;max-height:18px;background-color:rgb(245,245,245);padding:5px;color:rgb(34,34,34);font-family:arial;font-style:normal;font-weight:bold;font-size:13px;border:1px solid rgb(221,221,221);line-height:1"><a href="https://drive.google.com/a/students.mq.edu.au/file/d/1wQa7DmCIQyNs24Bn40G-yXoPlLqipTCr/view?usp=drive_web" target="_blank" style="display:inline-block;max-width:366px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration:none;padding:1px 0;border:none"><img style="vertical-align: bottom; border: none;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="color:rgb(17,85,204);text-decoration:none;vertical-align:bottom">f814w_01_flt.fits</span></a><img src="//ssl.gstatic.com/ui/v1/icons/common/x_8px.png" style="opacity: 0.55; cursor: pointer; float: right; position: relative; top: -1px; display: none;"></div><pre style="box-sizing:border-box;overflow:auto;font-family:monospace;font-size:14px;display:block;padding:1px 0px;margin:0px;line-height:inherit;color:rgb(0,0,0);word-break:break-all;background-color:rgb(255,255,255);border:0px none;border-radius:0px;white-space:pre-wrap;vertical-align:baseline;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial"><br></pre></div><div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr">Thanks and regards, <div>Shalmalee Kapse, <br></div><div>PhD Candidate,</div><div>Department of Physics and Astronomy,  <br></div><div>Macquarie University,NSW - 2109, Australia. <br></div></div></div></div></div></div></div></div>