  We present the Optimization Method for the Electron Multiplying
Charge-Coupled Devices (EMCCDs) of the Acquisition System of the SPARC4
(OMASS4). The OMASS4 uses as figures of merit the signal-to-noise ratio (SNR)
and the acquisition rate (AR) as a function of the operation mode of the CCDs.
Three different modes of optimization are included in the OMASS4: (1)
optimization of SNR only; (2) optimization of AR only; and (3) optimization of
both SNR and AR simultaneously. The first two modes calculate an analytical
maximization of the cost function whereas the third mode uses the bayesian
optimization method to determine the optimum mode of operation. We apply the
OMASS4 to find the optimum mode for observations obtained at the Pico dos Dias
Observatory, Brazil, and compare the delivered modes of operation and its
performance with the ones adopted by the observer. If the OMASS4 had been used
as a tool to optimize the CCDs in all of these nights, it would be possible to
improve their efficiency in 97.17 %, 65.08 %, and 77.66 % for the optimization
modes 1, 2, and 3, respectively.
