KEE friends are definitely not familiar with what is called a filter. Yup! This one object has quite a big influence on the results of the photo. That's why it's important for you to know how to clean the filter properly so that it lasts a long time.
1. If your filter is round like UV filters, CPL and ND filters, you can clean it like cleaning a camera lens. But don't use water because water can get into the optical surface of the filter so if it gets in, you have to disassemble the filter to clean it. In fact, it can be complicated, especially if you are not skilled at disassembling cameras.
2. You can use a micro fiber cloth or lens clearer sprayed on a soft cloth and wipe it on the filter. You can use lens clearer if there are stubborn stains.
3. Unlike the GND filter, to clean it you can run water over the surface of the filter and let it air, then wipe it using dry micro fiber. It is forbidden to use soap to clean this type of filter because it can cause damage.
4. Make sure the filter is completely dry on all parts and there is no dust attached.
5. Be careful when cleaning, especially the process of wiping the filter so that it doesn't get damaged.