My process. Good for any waterproof optic which hunting optics should be. 1. Rinse optic under slightly warm tap water to rid of anything that might scratch the lens. 2. Clean with ample amount of isopropyl alcohol and lens cleaning cloth (light circular motion) to remove grease/fingerprints/etc. Isopropyl alcohol is use in commercially prepared lens cleaning products. It will NOT harm the coatings. You can check online for MSDS data (required by law) which is available for ALL chemical products if you have doubts. Some cleaners contain Methanol but you can find isopropyl alcohol in any food or drug store. 3. Rinse with isopropyl alcohol. 4. Rinse with tap water. 4. Then rinse with distilled water. Lens will come out PRISTENE with ZERO spots. And it's cheap compare to a tiny spray bottle which usually contains, you guessed it, isopropyl alcohol or methanol and distilled water. Should be a sticky.