  The Extreme Universe Space Observatory - Super Pressure Balloon (EUSO-SPB2)
mission will fly two custom telescopes that feature Schmidt optics to measure
\v{C}erenkov- and fluorescence-emission of extensive air-showers from cosmic
rays at the PeV and EeV-scale, and search for tau-neutrinos. Both telescopes
have 1-meter diameter apertures and UV/UV-visible sensitivity. The \v{C}erenkov
telescope uses a bifocal mirror segment alignment, to distinguish between a
direct cosmic ray that hits the camera versus the \v{C}erenkov light from
outside the telescope. Telescope integration and laboratory calibration will be
performed in Colorado. To estimate the point spread function and efficiency of
the integrated telescopes, a test beam system that delivers a 1-meter diameter
parallel beam of light is being fabricated. End-to-end tests of the fully
integrated instruments will be carried out in a field campaign at dark sites in
the Utah desert using cosmic rays, stars, and artificial light sources. Laser
tracks have long been used to characterize the performance of fluorescence
detectors in the field. For EUSO-SPB2 an improvement in the method that
includes a correction for aerosol attenuation is anticipated by using a
bi-dynamic Lidar configuration in which both the laser and the telescope are
steerable. We plan to conduct these field tests in Fall 2021 and Spring 2022 to
accommodate the scheduled launch of EUSO-SPB2 in 2023 from Wanaka, New Zealand.
