  One of the strongest ${\rm Na~I}$ features was observed in WASP-96b. To
confirm this novel detection, we provide a new 475-825nm transmission spectrum
obtained with Magellan/IMACS, which indeed confirms the presence of a broad
sodium absorption feature. We find the same result when reanalyzing the
400-825nm VLT/FORS2 data. We also utilize synthetic data to test the
effectiveness of two common detrending techniques: (1) a Gaussian processes
(GP) routine, and (2) common-mode correction followed by polynomial correction
(CMC+Poly). We find that both methods poorly reproduce the absolute transit
depths but maintain their true spectral shape. This emphasizes the importance
of fitting for offsets when combining spectra from different sources or epochs.
Additionally, we find that for our datasets both methods give consistent
results, but CMC+Poly is more accurate and precise. We combine the
Magellan/IMACS and VLT/FORS2 spectra with literature 800-1644nm HST/WFC3
spectra, yielding a global spectrum from 400-1644nm. We used the PLATON and
Exoretrievals retrieval codes to interpret this spectrum, and find that both
yield relatively deeper pressures where the atmosphere is optically thick at
log-pressures between $1.3^{+1.0}_{-1.1}$ and 0.29$^{+1.86}_{-2.02}$ bars,
respectively. Exoretrievals finds a solar to super-solar ${\rm Na~I}$ and ${\rm
H_2O}$ log-mixing ratios of $-5.4^{+2.0}_{-1.9}$ and $-4.5^{+2.0}_{-2.0}$,
respectively, while PLATON finds an overall metallicity of
$log_{10}(Z/Z_{\odot}) = -0.49^{+1.0}_{-0.37}$dex. Therefore, our findings are
in agreement with literature and support the inference that the terminator of
WASP-96b has few aerosols obscuring prominent features in the optical to
near-infrared (near-IR) spectrum.
