I think I am doing a reasonable job taking care of my binoculars. That said, I'd like to tap into the vast body of knowledge and experience of this forum's members, so I am sharing what I am doing and would like to hear your feedback and suggestions.
My binoculars, when not in use, are stored away in moisture-proof boxes. One of the boxes already has a built-in dehumidifier but I've put some desiccant packs in there anyway for extra protection against moisture.
When stored away, my binos are never in their original cases. In fact, I don't use any of the original cases other than when taking some of my binoculars with me on short trips. When walking around town, I simply put my binos in a small shoulder bag. (It's a Manfrotto camera bag that doesn't look like a camera bag, and that holds a special appeal for me.)
My Canon 15x50 IS is always stored horizontally. (I've read a tip on CN that storing Canon IS binos horizontally can help keep the IS artifacts at bay. I am sure there's at the very least some truth to this as the tip comes from a very experienced CN member whose opinions and tips I highly respect and have greatly benefitted from. In any case, with the moisture-proof boxes that I have, it's way easier to store my Canon horizontally than to do so vertically, so there's no room for any debate here )
To prevent battery leakage in my Canon IS bino, I take the batteries out of the Canon every few days to recharge them using a Panasonic battery charger. (I have a 4-pack Panasonic Eneloop Pro and these Eneloop batteries work great with my Canon IS.)
2. UV-C sterilization:
My used Canon 15x50 IS arrived a couple of months ago in very good condition other than a small mold somewhere inside one of the eyepieces. This doesn't seem to impact the view in any way, but I've bought a UV-C sterilizer and put the Canon in there for a 20-30 min UV-C treatment every week to make sure that the mold does not spread. In addition, I've given the Canon the sunlight treatment multiple times to be doubly-sure that the mold is well and truly dead.
I've also given my other binos the same UV-C treatment for good measure.
3. Cooling down binoculars before use:
I've noticed that with my low-powered binos, which are in the 30mm and 40mm aperture classes, there's hardly any need to cool them down before use. Just take them out of their moisture-proof boxes and they seem to be instantly ready for action.
The same appears to hold true for my 50mm aperture class binos, though I've learned to give them some 5 minutes to acclimatize first, for best results.
I give my Nikon 18x70 some 10 mins before first use. The cool down period for my 82mm Kowa is a bit longer, at 30 mins or so.
I've heard that when cooling down binos, it's not necessary to take the objective/eyepiece covers off. The optics are better protected that way.
What I typically do in an observing session is to use my lower-powered, smaller-objective binos first to get macro views of the night sky. By the time I am ready for close-up studies, the bigger binos are about ready.
4. Packing up after use:
I never keep my optics outside over night, leaving them exposed to the elements. They always go back in their respective moisture-proof boxes after use each night.
5. Optics cleaning:
I've made some costly mistakes when cleaning my optics. I used to clean my optics obsessively after pretty much each session, introducing cleaning marks to some of my prized optics.
The optics cleaning procedure that I go by nowadays is the one nicely written up at:
What I haven't yet figured out is when and how often to do the cleaning. Should that be once a week, e.g. every Sun morning?
Do you do any cleaning at all after using your binoculars before packing them up for the night?
Would love to hear from you all. Thank you.