Fluid used in cleaning the lenses?

The fluid commonly used for cleaning lenses is typically a lens cleaner solution, which is designed to effectively remove dirt, smudges, and oils without damaging the lens coating. These solutions often contain mild surfactants and are alcohol-free to prevent streaking and potential harm to the lens material. Alternatively, distilled water or a mixture of water and vinegar can also be used for gentle cleaning. Always use a microfiber cloth to avoid scratching the lens surface.