  When observing transmission spectra produced by atmospheres of ultra-hot
Jupiters, large telescopes are typically the instrument of choice due to the
very weak signal of the planet's atmosphere. This study aims to alleviate the
desire for large telescopes by illustrating that the same science is possible
with smaller telescope classes. We use the cross-correlation technique to
showcase the potential of the high-resolution spectrograph FOCES at Wendelstein
Observatory and demonstrate its potential to resolve the atmosphere of the
ultra-hot Jupiter, KELT-9 b. A performance comparison is conducted between
FOCES and HARPS-N spectrographs, considering both single transit and combined
observations over three nights. With FOCES, we have detected seven species in
KELT-9 b's atmosphere: Ti II, Fe I, Fe II, Na I, Mg I, Na II, Cr II, Sc II.
Although HARPS-N surpasses FOCES in performance, our results reveal that
smaller telescope classes are capable of resolving ultra-hot Jupiter
atmospheres. This broadens the scope of potential studies, allowing for
investigations into phenomena like temporal variations in atmospheric signals
and the atmospheric loss characteristics of these close-in planets.
