In this study, we conduct a comparative analysis of observations carried out on the exoplanet HAT-P-25b at the Sharjah Astronomical Observatory (SAO). We have employed two distinct filters, namely, the Luminoso ( \(L\) ) and Visual ( \(V\) ) filters. Our research conducted aims to discern any variations in transit depth or exoplanet size resulting from the use of these different filters. The primary focus of this study is to determine the exoplanet’s size relative to its host star using the transit method. The application of different filters was expected to introduce subtle variations in size, influenced by factors such as the exoplanet’s atmosphere. Notably, our findings reveal that the exoplanet’s size appears larger when observed through the L filter compared to the V filter. Throughout the analytical process, we employed the TRASCA model to determine the transit depth for each epoch. Fixed parameters, including the orbital period of the exoplanet ( \(P\) , measured in days) and the transit duration (measured in minutes), were utilized in these calculations. Our results indicate that the transit depths observed with the \(L\) filter were greater than those with the \(V\) filter, measuring \(0.0238\) magnitudes and \(0.0200\) magnitudes, respectively. These values deviate from the reference result of \(0.0204\) magnitudes.