A comparative study of two methodologies for optical studies on materials is reported. The first method focusses on calibrating Homemade spectrometer with spectral wavelengths associated with a standard mercury source (492 nm 619 nm). The next step was measuring the transmittance of dilute liquid samples using a Homemade spectrometer working in transmittance mode (refereed as TSS). The objective is to test Beer Lambert's law for dilute solutions of methylene blue, traditionally analyzed with a standard Laboratory Colorimeter (LC). Results from the TSS comply with those obtained from LC. The second method focusses on using monochromatic LEDs, with wavelengths in the range (390 nm to 665 nm) as light source. The light emerging from these LEDs is incident on doped polysulfone polymer membranes. Phase inversion method is utilized to prepare the membranes, composed of polysulfone (PSF), polyvinyl pyrrolidone (PVP), and N methyl 2 pyrrolidone (NMP). These membranes are doped with nano particle additives of Ag, Fe3O4 and/or CNTs. The reflectance from these polymer membrane samples—each with a different dopant or a combination of two dopants in the polymer matrix—is used to determine the absorption coefficient of the individual polymer membranes. Unlike the case of TSS, these results obtained for RSP (Reflectance mode Spectrometer using a Photodiode as a light detector) are not yet verified by a standard spectrometer working in reflectance mode, although the absorption peaks deciphered from the reflectance data correlates with the presence of the specific additive/s in the membrane. Components used for constructing both the Homemade spectrometers are available in any engineering physics laboratory. The experimental results of both the Homemade spectrometers—Transmittance mode Spectrometer with a Solar cell as a light detector (TSS) and another, a Reflectance mode Spectrometer using a Photodiode as a light detector (RSP)—demonstrates their efficacies in undergraduate research settings.