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Recent research has indicated that passive extended shortwave infrared (eSWIR) imaging systems display superior range performance to systems operating in the other reflective bands—the visible, near infrared, and shortwave infrared (SWIR)—in some degraded visual environments (DVEs). However, it cannot be immediately concluded that this trend extends to active imaging systems: the radiometry of active systems and the atmospherics of DVEs possess intertwining complexities that prevent such a generalization. This research modeled and compared the range performance of four active imaging systems comprising two active imaging modes, continuous wave (CW) and laser range-gated (LRG), and two wavelengths, 1.625 μm in the SWIR and 2.141 μm in the eSWIR, in eight different DVEs: black and white smoke, radiative and advective fog, static and transported desert dust, non-desert dust, and rain. Modeling was conducted using two software suites: the U.S. Air Force Institute of Technology’s LEEDR, which models laser propagation through user-defined atmospheres, and the U.S. Army DEVCOM’s Night Vision Integrated Performance Model (NV-IPM), which models imaging system performance. In these models, eSWIR displayed marginally longer range performance than SWIR in most DVEs, and LRG systems displayed significantly longer range performance than CW systems in all DVEs. The driving factor in the band comparison was determined to be scattering regimes: eSWIR carries a significant range advantage over SWIR in atmospheres dominated by Rayleigh scattering, whereas there is little difference between the two bands in atmospheres dominated by Mie scattering. The driving factor in the imaging mode comparison was determined to be laser backscatter: LRG systems eliminate the collection of most backscatter, where CW systems do not. A simple, preliminary field test using white smoke shows qualitative agreement with the results of the modeling.