Photometry

With spectra in hand we can produce photometry by combining the Sed object containing the (multidimensional) spectra with a FilterCollection defining the transmission curve of a set of filters. Doing so produces a PhotometryCollection containing the photometry, its units, and methods for manipulating and visualising the photometry. Once photometry has been generated it can be used to produce images; for more details see the [imaging docs](../imaging/imaging.rst).

Note

For performance, filter-specific integration “artifacts” (i.e. constant values related to the integration of the transmission curve) are cached and reused when repeated photometry is evaluated on the same prepared wavelength/frequency grids.

In the pages below we demonstrate how to produce and use photometry.

• Generating Photometry
  • Plotting photometry
• Generating photometry from a Galaxy
  • Calculating light radii
  • Calculating weighted attributes