Cleaning them should not be that hard really, but it can depend on the monocular you have. Not all monoculars are the same and some are harder to clean even. I have the monocular from https://www.atncorp.com/thermal-monoculars and cleaning it was the easiest thing that I had to do. It makes hunting even easier because I can use it to see the animals that are far away from me. If you ever need a monocular you should check the one from ATN because it is great.