Photometry.jl

This is a package for performing astronomical photometry using modern and efficient algorithms.

Inspired by photutils, SEP, and AperturePhotometry.jl.

Usage

Here is a basic example to do some aperture photometry using CircularAperture. The photometry function performs the photometry using a given method. Please see the documentation for more examples and reference material.

data = ones(100, 100)
err = ones(100, 100)

ap1 = CircularAperture(50, 50, 3)
# partial overlap
ap2 = CircularAperture(0.5, 0.5, 5)

results = photometry([ap1, ap2], data, err)
@assert results.aperture_sum[1] ≈ 9π
@assert results.aperture_sum[2] ≈ 25π / 4

results

Output:

Table with 4 columns and 2 rows:
     xcenter  ycenter  aperture_sum  aperture_sum_err
   ┌─────────────────────────────────────────────────
 1 │ 50.0     50.0     28.2743       5.31736
 2 │ 0.5      0.5      19.635        4.43113

Contributing

Please see the to-do list above for project ideas as well as any open issues! If you add new functionality, please add appropriate documentation and testing. In addition, please increment the minor version of the package to reflect the new changes!

Tests are run with ParallelTestRunner.jl, which hooks into the standard Pkg.test harness for more granular control. See below for some brief usage examples run from the package root directory:

julia --proj

julia> using Pkg

List available testsets:

julia> Pkg.test("Photometry"; test_args=`--list`);
# ...
     Testing Running tests...
Available tests:
 - aperture/circular
 - aperture/elliptical
 - aperture/overlap
 - aperture/photometry
 - aperture/plotting
 - aperture/rectangle
 - backgroud/background
 - backgroud/estimators
 - backgroud/interpolators
 - detection/detection
     Testing Photometry tests passed

Run a subset of testsets in verbose mode, and enable default threading:

julia> Pkg.test("Photometry"; test_args=`--verbose aperture`, julia_args=`--threads=auto`);
# ...
     Testing Running tests...
Running 3 tests in parallel. If this is too many, specify the `--jobs=N` argument to the tests, or set the `JULIA_CPU_THREADS` environment variable.
                          │          │ ──────────────── CPU ──────────────── │
Test             (Worker) │ Time (s) │ GC (s) │ GC % │ Alloc (MB) │ RSS (MB) │
aperture/photometry   (1) │        started at 2025-10-21T16:36:40.959
aperture/overlap      (2) │        started at 2025-10-21T16:36:40.959
aperture/plotting     (3) │        started at 2025-10-21T16:36:40.959
aperture/plotting     (3) │     6.33 │   0.59 │  9.3 │     638.40 │   733.98 │
aperture/circular     (3) │        started at 2025-10-21T16:36:49.971
aperture/overlap      (2) │     8.83 │   0.61 │  6.9 │     744.02 │   733.98 │
aperture/elliptical   (2) │        started at 2025-10-21T16:36:52.293
aperture/circular     (3) │     1.61 │   0.00 │  0.0 │     160.19 │   733.98 │
aperture/rectangle    (3) │        started at 2025-10-21T16:36:52.571
aperture/elliptical   (2) │     0.74 │   0.00 │  0.0 │      79.68 │   733.98 │
aperture/rectangle    (3) │     1.56 │   0.00 │  0.0 │     142.79 │   734.75 │
aperture/photometry   (1) │    19.37 │   0.94 │  4.8 │    2712.83 │   821.66 │

Test Summary:           | Pass  Total   Time
  Overall               | 9478   9478  24.1s
    aperture/plotting   |   27     27   6.3s
    aperture/overlap    | 9226   9226   8.8s
    aperture/circular   |   21     21   1.6s
    aperture/elliptical |   20     20   0.7s
    aperture/rectangle  |   12     12   1.6s
    aperture/photometry |  172    172  19.4s
    SUCCESS
     Testing Photometry tests passed

License

The work derived from astropy/photutils is BSD 3-clause and the work derived from kbarbary/sep is BSD 3-clause. All other work is considered MIT expat. Therefore this work as a whole is BSD 3-clause. LICENSE contains all licenses and any files using derived work are noted at the top of the file.