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This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., Radio astronomy is undergoing a renaissance, as the next generation of instruments provides a massive leap forward in collecting area and therefore raw sensitivity. However, to achieve this theoretical level of sensitivity in the science data products, we need to address the much more pernicious systematic effects, which are the true limitation. These become all the more significant when we consider that much of the time used by survey instruments, such as the Square Kilometre Array (SKA), will be dedicated to deep surveys. CHILES is a deep H i survey of the COSMOS field, with 1000 hr of Very Large Array time. We present our approach for creating the image cubes from the first epoch, with discussions of the methods and quantification of the data quality from 946 to 1420 MHz—a redshift range of 0.5−0. We lay out the problems we had to solve and describe how we tackled them. These are important because CHILES is the first deep wide-band multiepoch H i survey and has relevance for ongoing and future surveys. We focus on the accumulated systematic errors in the imaging, as the goal is to deliver a high-fidelity image that is only limited by the random thermal errors. To understand and correct these systematic effects, we ideally manage them in the domain in which they arise, and that is predominately the visibility domain. CHILES is a perfect test bed for many of the issues we can expect for deep imaging with the SKA or ngVLA, and we discuss the lessons we have learned. © 2022. The Author(s). Published by the American Astronomical Society., he CHILES survey was partially supported by a collaborative research grant from the National Science Foundation under grant Nos. AST—1412843, 1412578, 1413102, 1413099, and 1412503. This research was supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in three Dimensions (ASTRO-3D), through project No. CE170100013, and by grants from Amazon Web Services, the AstroCompute project. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement with Associated Universities Inc. Source flux densities in Table 2 were taken from the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. J.M.v.d.H. acknowledges support from the European Research Council under the European Unions Seventh Framework Programme (FP/2007-2013)/ERC grant agreement No. 291531 (HIStoryNU). D.J.P., N.L., and E.S. acknowledge partial support from NSF grants No. AST 1412578 and AST-1149491 and from the WVU Eberly College Dean's office. K. R. acknowledges support from the Bundesministerium für Bildung und Forschung (BMBF) award 05A20WM4. K.M.H. acknowledges funding from the State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the "Center of Excellence Severo Ochoa" awarded to the Instituto de Astrofísica de Andalucía (SEV-2017-0709); from grant RTI2018-096228-B-C31 (Ministry of Science, Innovation and Universities/State Agency for Research/European Regional Development Funds, European Union); and from the coordination of the participation in SKA-SPAIN, funded by the Ministry of Science and innovation (MICIN).