DOLPHOT is a stellar photometry package that was adapted from HSTphot for general use. It currently supports two modes. One is a generic PSF-fitting package, which uses analytic PSF models and can be used for any camera. The second mode uses ACS PSFs and calibrations, and is effectively an ACS adaptation of HSTphot. A number of utility programs are also included iwth the DOLPHOT distribution, including basic image reduction routines.

If you make use of DOLPHOT in your work, please cite Dolphin (2000) and Dolphin (2016).

DOLPHOT 1.0 base sources (updated 14 Mar 2007)
DOLPHOT 1.1 base sources (updated 6 Sep 2010)
DOLPHOT 1.2 base sources (updated 25 Jan 2011)
DOLPHOT 2.0 base sources (updated 9 Dec 2022)
DOLPHOT 2.0 manual (also included in base sources)
HSTphot paper (from PASP website)

DOLPHOT 1.0 ACS module sources (updated 11 Feb 2007)
DOLPHOT 1.1 ACS module sources (updated 6 Sep 2010)
DOLPHOT 1.2 ACS module sources (updated 14 Nov 2010)
DOLPHOT 2.0 ACS module sources (updated 24 Feb 2016)
DOLPHOT 2.0 ACS module manual (also included in sources)

DOLPHOT 1.1 WFC3 module sources (updated 6 Sep 2010)
DOLPHOT 1.2 WFC3 module sources (updated 25 Jan 2011)
DOLPHOT 2.0 WFC3 module sources (updated 26 Aug 2017)
DOLPHOT 2.0 WFC3 module manual (also included in sources)

DOLPHOT 1.1 WFPC2 module sources (updated 6 Sep 2010)
DOLPHOT 1.2 WFPC2 module sources (updated 14 Nov 2010)
DOLPHOT 2.0 WFPC2 module sources (updated 20 Jan 2018)
DOLPHOT 2.0 WFPC2 module manual (also included in sources)

Note that this code has had limited usage. Please provide feedback if you use this code, as it will be greatly appreciated whether or not there were issues.

If you make use of the JWST NIRCAM module in your work, please cite Weisz et al. in prep in addition to the DOLPHOT references (Dolphin 2000 and Dolphin 2016). For more information on the JWST ERS program that is developing this module (as well as a companion NIRISS module), please see https://ers-stars.github.io.

Notes and Limitations

• Photometry calibrations were updated with CRDS context file jwst_1126.pmap. For data obtained before that context file was added to the pipeline, it is recommended to re-retrieve the data.
• Stage 2 Data Quality (DQ) arrays produced by the pipeline are not reliable enough for use. In the current release, (a) pixels flagged as saturated by the pipeline (DQ array value of 2) are considered saturated, (b) other pixels masked out by the pipeline (Science array value is exactly zero or NaN) are considered bad pixels, and (c) all other pixels are assumed good.
• DOLPHOT currently uses the file data in the FITS headers, rather than what is provided in the ASDF extension.
• DOLPHOT does not yet support NIRCAM subarray observing modes.
• Impacts from time variability of the PSFs not yet quantified. Initial indications are that the PSF is general stable, but rare, extreme PSF variations are not handled well.

DOLPHOT 2.0 NIRCAM module sources (updated 2 Dec 2023)
DOLPHOT 2.0 NIRCAM module manual (also included in sources)

Note that this code has had limited usage. Please provide feedback if you use this code, as it will be greatly appreciated whether or not there were issues.

If you make use of the JWST NIRCAM module in your work, please cite Weisz et al. in prep in addition to the DOLPHOT references (Dolphin 2000 and Dolphin 2016). For more information on the JWST ERS program that is developing this module (as well as a companion NIRCam module), please see https://ers-stars.github.io.

Known Limitations

• Comparison of the model PSFs (from WebbPSF) to images in NIRISS F090W and F150W indicate the model PSFs are much too sharp. It is unlikely that DOLPHOT can produce reliable photometry until this has been resolved.
• Photometry calibrations were updated with CRDS context file jwst_0895.pmap. For data obtained before that context file was added to the pipeline, it is recommended to re-retrieve the data.
• Stage 2 Data Quality (DQ) arrays have not been thoroughly tested for reliability. In the current release, (a) pixels flagged as saturated by the pipeline (DQ array value of 2) are considered saturated, (b) other pixels masked out by the pipeline (Science array value is exactly zero) are considered bad pixels, and (c) all other pixels are assumed good.
• DOLPHOT currently uses the file data in the FITS headers, rather than what is provided in the ASDF extension.
• DOLPHOT does not yet support NIRISS subarray observing modes.

Possible Limitations (Testing in Progress)

• Limited testing to date has been performed only on data obtained by program JWST-ERS-01334
• Comparison of observational CMDs to isochrones and/or synthetic CMDs (e.g., as a check on zero points and calibrations) not yet performed
• Impacts from time variability of the PSFs not yet assessed
• Testing combined photometry with NIRISS and other instruments not yet performed

DOLPHOT 2.0 NIRISS module sources (updated 2 Dec 2023)
DOLPHOT 2.0 NIRISS module manual (also included in sources)

Note that this code has had limited usage. Please provide feedback if you use this code, as it will be greatly appreciated whether or not there were issues.

If you make use of the JWST MIRI module in your work, please cite Peltonen et al prep in addition to the DOLPHOT references (Dolphin 2000 and Dolphin 2016).

Known Limitations

• On-orbit gain, and on-orbit readout noise have not yet been incorporated.
• A current limitation to the PSF models is that the cruciform structure has not yet been incorporated into the optical model.
• Stage 2 Data Quality (DQ) arrays have not been thoroughly tested for reliability. In the current release, (a) pixels flagged as saturated by the pipeline (DQ array value of 2) are considered saturated, (b) other pixels masked out by the pipeline (Science array value is exactly zero) are considered bad pixels, and (c) all other pixels are assumed good.
• DOLPHOT currently uses the file data in the FITS headers, rather than what is provided in the ASDF extension.
• DOLPHOT does not yet support MIRI subarray observing modes.

Possible Limitations (Testing in Progress)

• Limited testing to date has been performed only on data obtained by program JWST-GO-02128
• Comparison of observational CMDs to isochrones and/or synthetic CMDs (e.g., as a check on zero points and calibrations) not yet performed
• Impacts from time variability of the PSFs not yet assessed

Longer Term Enhancements

• Identification of optimal DOLPHOT parameters for both short and long modes
• Incorporation and testing of additional empirical PSF libraries
• Testing combined photometry with MIRI and other instruments

DOLPHOT 2.0 MIRI module sources (updated 2 Dec 2023)
DOLPHOT 2.0 MIRI module manual (also included in sources)

DOLPHOT 2.0 Roman module sources (updated 26 Aug 2017)
DOLPHOT 2.0 Roman module manual (also included in sources)