  This paper describes the characterization of the GALANTE photometric system,
a seven intermediate- and narrow-band filter system with a wavelength coverage
from 3000 $\r{A}$ to 9000 $\r{A}$ . We describe the photometric system
presenting the full sensitivity curve as a product of the filter sensitivity,
CCD, telescope mirror, and atmospheric transmission curves, as well as some
first- and second-order moments of this sensitivity function. The GALANTE
photometric system is composed of four filters from the J-PLUS photometric
system, a twelve broad-to-narrow filter system, and three exclusive filters,
specifically designed to measure the physical parameters of stars such as
effective temperature $T_{\rm eff}$, $\log(g)$, metallicity, colour excess
$E(4405-5495)$, and extinction type $R_{5495}$. Two libraries, the Next
Generation Spectral Library (NGSL) and the one presented in Ma\'iz Apell\'aniz
& Weiler (2018), have been used to determine the transformation equations
between the Sloan Digital Sky Survey ($\textit{SDSS}$) $\textit{ugriz}$
photometry and the GALANTE photometric system. We will use this transformation
to calibrate the zero points of GALANTE images. To this end, a preliminary
photometric calibration of GALANTE has been made based on two different
$\textit{griz}$ libraries ($\textit{SDSS}$ DR12 and ATLAS All-Sky Stellar
Reference Catalog, hereinafter $\textit{RefCat2}$). A comparison between both
zero points is performed leading us to the choice of $\textit{RefCat2}$ as the
base catalogue for this calibration, and applied to a field in the Cyg OB2
association.
