Is oil immersion needed to determine morphology of prokaryotes?

Oil immersion is not strictly necessary to determine the morphology of prokaryotes, but it can enhance the clarity and resolution of the observed cells under a microscope. Using oil immersion lenses, typically at 100x magnification, allows for greater detail in visualizing small structures, such as the shape and arrangement of bacteria. However, prokaryotic morphology can still be assessed using lower magnifications without oil, although the details may be less discernible.