  The ELAIS-S1 field will be an LSST Deep Drilling field, and it also has
extensive multiwavelength coverage. To improve the utility of the existing
data, we use The Tractor to perform forced-photometry measurements in this
field. We compile data in 16 bands from the DeepDrill, VIDEO, DES, ESIS, and
VOICE surveys. Using a priori information from the high-resolution fiducial
images in VIDEO, we model the images in other bands and generate a
forced-photometry catalog. This technique enables consistency throughout
different surveys, deblends sources from low-resolution images, extends
photometric measurements to a fainter magnitude regime, and improves
photometric-redshift estimates. Our catalog contains over 0.8 million sources
covering a 3.4 deg2 area in the VIDEO footprint and is available at
10.5281/zenodo.4540178.
