Downloading Data in Finder Chart

Contents of page/chapter:
+Overview
+Options for Downloading Data (including reprojection)
+Downloading Script
+Acknowledgments

 

Overview

On any search results page, click "Prepare Download" (near the top left of the image results window pane) to begin the packaging (and downloading) process. A pop-up window will appear in order to define exactly what kinds of data you would like to have packaged up. Select what you want, and click "prepare download."

The packaging process spins off into the background monitor, which keeps track of its progress and notifies you when the downloads are complete. You can choose to have an email sent to you to let you know when things are ready, even after the packaging process has started.

Note that you control where the data are saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. Look for a "Downloads" folder or search for recently modified files.

Now, we cover the various options for downloading data in much more detail.

Options for Downloading Data

If you just quickly want a copy of the current images of the current target, you can choose the PDF icon () on the upper right, and it will generate a single-page PDF with all the images for your current target. You can then save it to disk for later viewing or printing. The search parameters will appear on the top of the PDF page.

For more complex situations, click on the "Prepare Download" button (near the top left of the image results window pane). You will obtain a pop-up window, which looks like this:

In the download pop-up, there are several options.

Current target/All targets
If you searched for multiple targets, the first row asks if you would like the data for just the current target, or for all the targets on which you searched. If you searched on only one target, this row does not appear, because it assumes you want the one target on which you searched.

File type: FITS, HTML, PDF, PNG
You can select FITS files, HTML (plus associated) files, PDF files, or PNG files.

Separate by Object
If you searched for multiple targets, you can choose to have the files separated into subdirectories for each of your targets, or all in one directory (a flat file structure). This option does not appear when downloading data from only one target.

Include Color Images
You can choose to save the color images as well as the single-color-plane images. This option only makes sense in the context of HTML or PNG files.It is particularly powerful for saving color images, automatically generated, for all your batch search targets at once.

Reprojected (north up).
You can choose to have the images reprojected. Selecting this option rotates all the images to strictly north-up (many images may already be north-up by default, or close to it), preserving flux, and resamples the images to all be the same pixel size, 0.36 arcsec. Do not select this option cavalierly, because it can take a very long time, especially for big images. (It is a non-linear process in that an image that is twice as big takes more than twice as long to reproject.) It is using Montage (specifically the library mProjectPP) on IPAC's servers to do this reprojection; please see the Montage documentation for more details on what, exactly, it is doing. To reproject the images on your own (selecting your own pixel size, for example), download the original images, and then download, install, and use the Montage software, which is is freely available for a variety of platforms.

Page Layout
This option controls how the HTML or PDF pages are generated -- one per target, or one per image set (all images from a given survey). This option only makes sense in the context of HTML or PDF pages, because it is only in these cases where there is a page to lay out in the first place.

Email
You have an option to provide an email address to which it will send an email when the packaging is done. (Within the same Finder Chart session, Finder Chart remembers what you have entered before, but when initiating a new Finder Chart session, you will have to re-enter this information.) This is useful if you are generating PDFs or color PNGs -- anything that takes longer than a few seconds to a few minutes.

After customizing all of that, click "Prepare Download" in the pop-up window, and it will go do it!

When it packages up the data, it will spin off this packaging process to the background monitor and create zip files. This process could be virtually instantaneous, or take some time. You can watch it in the background monitor. If your packaging is taking longer than expected, you can add an email address mid-stream, and it will email you when it is done.

Downloading Script

The Download Retrieval Script dialog gives you some options regarding which script you want to use. Generally speaking, the wget script is best for Linux and Unix users. The curl script is best for Mac users, because curl is part of the standard OS distribution; Mac users can also go retrieve and install wget and then use the wget scripts. For any of the scripts, you can also choose to include an option that unzips the zip files automatically. The files stay on disk here for at least 72 hours, so you have a window of time to download them.

Save the script to a plain text file, and invoke the script. You can copy and paste the script lines individually into your terminal window, or by typing "csh [yourtextfile]" at the prompt. The files will be automatically and sequentially downloaded to your disk, and if you've selected that option, unzipped as well.

For Windows users, download and save the text file of URLs . Then follow the following steps to install the wget script and then download your data:

  1. Go to the Windows wget web page
  2. Scroll to the Download section and retrieve the wget installation.
  3. Install wget and add the binary to your path.
  4. Download the text file of URLs
  5. At the command prompt: wget --content-disposition -i <file_of_urls_downloaded.txt>

Depending on how, exactly, you unzip your files, your computer may put the contents of each zipfile into one directory, rather than, say, the contents of each observation into one directory (which was the original design, and the conceptually most straightforward). If you are using a GUI-based method (e.g., click to uncompress), there should be a preferences option to allow you to uncompress subsequent zipfiles into the same root directory. If you use the download script above, the flags sent on the command line that unzip the files should put all files from the same observation in the same directory.

Acknowledgments

The standard IRSA acknowledgment is:
This research has made use of the NASA/ IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

The standard POSS/DSS acknowledgment is:

The Digitized Sky Survey was produced at the Space Telescope Science Institute under U.S. Government grant NAG W-2166. The images of these surveys are based on photographic data obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt Telescope. The plates were processed into the present compressed digital form with the permission of these institutions."

The standard SDSS acknowledgment is:

Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III web site is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, University of Cambridge, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University.

The standard 2MASS acknowledgment is:

This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

The standard WISE acknowledgment is:

This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration.