panstamps

Documentation Status Coverage Status

A python package and command-line tools to download stacked and/or warp image stamps from the STScI PanSTARRS image server.

Note

If working with warped PS1 images then you need to work off a machine that has an IP address whitelisted by the Pan-STARRS1 data archive, otherwise only stacked images will be available to you. Also w-band images are not (yet) accessible from the data archive.

Here’s a summary of what’s included in the python package:

Classes

panstamps.downloader Tools to download the panstarrs image stamps from STScI PanSTARRS image server
panstamps.image.image The worker class for the image module

Functions

Installation

The easiest way to install panstamps is to use pip:

pip install panstamps

Or you can clone the github repo and install from a local version of the code:

git clone git@github.com:thespacedoctor/panstamps.git
cd panstamps
python setup.py install

To upgrade to the latest version of panstamps use the command:

pip install panstamps --upgrade

Troubleshooting on Mac OSX

panstamps uses pillow (a fork of the Python Imaging Library) which requires some external libraries.

If you have issues running panstamps on OSX, try installing Homebrew and running:

brew install libtiff libjpeg webp little-cms2

Development

If you want to tinker with the code, then install in development mode. This means you can modify the code from your cloned repo:

git clone git@github.com:thespacedoctor/panstamps.git
cd panstamps
python setup.py develop

Pull requests are welcomed!

Sublime Snippets

If you use Sublime Text as your code editor, and you’re planning to develop your own python code with panstamps, you might find my Sublime Snippets useful.

Issues

Please report any issues here.

Command-Line Usage

Documentation for panstamps can be found here: http://panstamps.readthedocs.org/en/stable

Usage:
    panstamps [options] [--width=<arcminWidth>] [--filters=<filterSet>] [--settings=<pathToSettingsFile>] [--downloadFolder=<path>] (warp|stack) <ra> <dec> [<mjdStart> <mjdEnd>]
    panstamps [options] --closest=<beforeAfter> [--width=<arcminWidth>] [--filters=<filterSet>] [--settings=<pathToSettingsFile>] [--downloadFolder=<path>] <ra> <dec> <mjd>

    -h, --help                              show this help message
    -f, --fits                              download fits (default on)
    -F, --nofits                            don't download fits (default off)
    -j, --jpeg                              download jepg (default off)
    -J, --nojpeg                            don't download jepg (default on)
    -c, --color                             download color jepg (default off)
    -C, --nocolor                           don't download color jepg (default on)
    -a, --annotate                          annotate jpeg (default true)
    -A, --noannotate                        don't annotate jpeg (default false)
    -t, --transient                         add a small red circle at transient location (default false)
    -T, --notransient                       don't add a small red circle at transient location (default true)
    -g, --greyscale                         convert jpeg to greyscale (default false)
    -G, --nogreyscale                       don't convert jpeg to greyscale (default true)
    -i, --invert                            invert jpeg colors (default false)
    -I, --noinvert                          don't invert jpeg colors (default true)
    --width=<arcminWidth>                   width of image in arcsec (default 1)
    --filters=<filterSet>                   filter set to download and use for color image (default gri)
    --downloadFolder=<path>                 path to the download folder, relative or absolute (folder created where command is run if not set)
    --settings=<pathToSettingsFile>         the settings file
    --closest=<beforeAfter>                 return the warp closest in time to the given mjd. If you want to set a strict time window then pass in a positive or negative time in sec (before | after | secs)

    ra                                      right-ascension in sexagesimal or decimal degrees
    dec                                     declination in sexagesimal or decimal degrees
    mjdStart                                the start of the time-window within which to select images
    mjdEnd                                  the end of the time-window within which to select images
    mjd                                     report the warp closest in time to this mjd

Documentation

Documentation for panstamps is hosted by Read the Docs (last stable version and latest version).

Command-Line Tutorial

There are 2 ways to use panstamps, either via the command-line or import it into your own python code and use it from there.

Command-Line

Full usage options can be found by typing:

panstamps -h

Here I’ll run through the basics. By default the command will only download the fits files for the location given. To download the stack fits cutouts for M82 run the command:

panstamps stack 09:55:52.2 +69:40:47

By default the gri filter, 1 arcmin fits cutouts are downloaded:

https://i.imgur.com/DRvOiZ1.png https://i.imgur.com/3u9gVBW.png

To increase the image width and download all filters, run the command:

panstamps --width=4 --filters=griyz stack 09:55:52.2 +69:40:47

As you can see we now have a larger cutout:

https://i.imgur.com/ST9Y6Wv.png

JPEGS

To download the jpegs, and not the fits files rerun the command with the correct flags set. We’ll also use the --downloadFolder option to assign the download directory.

panstamps -Fj --width=4 --filters=gri --downloadFolder=/Users/Dave/Desktop/m81 stack 09:55:52.2 +69:40:47

This downloads the jpegs and adds some useful annotation, which can be switched off if required.

https://i.imgur.com/yxPjt4U.png

Sometimes it maybe useful to add a transient marker at the centre of the image:

panstamps -FjAt --width=4 --filters=gri --downloadFolder=/Users/Dave/Desktop/m81 stack 09:55:52.2 +69:40:47
https://i.imgur.com/SDoYvR7.png

Or grab the color image as well as/instead of the single filter images:

panstamps -FJc --width=4 --filters=gri --downloadFolder=/Users/Dave/Desktop/m81 stack 09:55:52.2 +69:40:47
https://i.imgur.com/f5ixUts.png

Note the code will try its best to choose a colour for the annotation lines and text to make them contrast well against the background image.

Finally you can invert the image colors or convert the image to greyscale:

panstamps -FJci --width=4 --filters=gri --downloadFolder=/Users/Dave/Desktop/m81 stack 09:55:52.2 +69:40:47
https://i.imgur.com/rrcAsRN.png
panstamps -FJcig --width=4 --filters=gri --downloadFolder=/Users/Dave/Desktop/m81 stack 09:55:52.2 +69:40:47
https://i.imgur.com/g4w8Mv3.png

Temporal Constraints (Useful for Moving Objects)

For moving objects, alongside spatially filtering the panstarrs images, we also require a temporal filter. We need to be able to request images at a sky-position that were taken within a given time range. With panstamps we have the option of passing a time-window to filter the images by via the mjdStart and mjdEnd variables:

For example I can run:

panstamps -Fj --width=4 --filters=gri --downloadFolder=~/Desktop/movers warp 189.1960991 28.2374845 55246.63 55246.64

to only return the 2 images I want within the temporal window at the location in the sky.

It’s also possible to request the closest warp image taken before or after a requested MJD by using the closest flag. For example, to request the closest r-band warp taken before MJD=`55246.64` for the location above, run the command:

panstamps -Fj --closest=before --width=4 --filters=gri --downloadFolder=~/Desktop/movers 189.1960991 28.2374845 55246.64

To request the closest warp taken after the given MJD then use --closest=after.

Oftentimes it’s useful to download the closest warp within a given time-window, e.g. closest warp in time of the requested MJD taken up to 3 mins before. To do so pass in a postive or negative integer to represent the time-window in seconds, like so:

panstamps -Fj --closest=-120 --width=4 --filters=gri --downloadFolder=~/Desktop/movers 189.1960991 28.2374845 55246.64

Importing to Your Own Python Script

To use panstamps within your own scripts please read the full documentation. But for those of you that can’t wait, this snippet should give you the basics:

from panstamps.downloader import downloader
from panstamps.image import image
fitsPaths, jpegPaths, colorPath = downloader(
    log=log,
    settings=False,
    downloadDirectory=False,
    fits=False,
    jpeg=True,
    arcsecSize=600,
    filterSet='gri',
    color=True,
    singleFilters=True,
    ra="70.60271",
    dec="-21.72433",
    imageType="stack",  # warp | stack
    mjdStart=False,
    mjdEnd=False,
    window=False
).get()

for j in jpegPaths:

    myimage = image(
        log=log,
        settings=False,
        imagePath=j
        arcsecSize=120,
        crosshairs=True,
        transient=False,
        scale=True,
        invert=False,
        greyscale=False
    ).get()