Caps or covers. Things I do not want caps on in the field (RDS, most LPVOs) get a hotel room key card (I have zillions) balanced on top of it in the rack.
Electronics get lithium or dielectric grease on the o-rings and threads for all the battery caps. From the box, usually. 99.5% of stuff comes from the factory dry, and won't stay as water tight, can become stuck or damaged.
(remainder copied from my own post on lens cleaning LF.net)
Every environment is dusty. It's always abrasive, so best to assume even your house is dangerously dusty, so the most desert/lakebed/wasteland, just the more you need to remember the proper methods, carry stuff with you.
I say/was taught:
- Air over brush
- Brush over wiping
- Wiping always wet
Get a small blower with brush from a camera store. Like this;
Today I learned, the brush comes off the end
It works all together, doesn't need to. Blow as much off as you can. IF you must, use the very very soft brush to wipe away more, then blow that off also. Occasionally flick the brush to get the dust off it as we'll discuss more in a minute.
Get a bigger one for home. I like this Giotto one because it's a rocket and is very very good:
Lots of air, deals with most issues. The rocket bit also means it stays upright as shown so doesn't get dirty etc.
For more dirty, such as when it rains (or just condensates) on your dusty lenses, you wipe. Wet. Always wet. Turn it lens up, flood the area with Windex (or similar, but not like denatured alcohol, as that can dry out the rubber seals holding the lenses in, etc). Use a disposable wipe and go in a very tight spiral from the center outward.
The edges are the most dirty so you want to clean them last, and also less important optically if they are dirty or even scratched. May be other stuff with optics going on, all I know is people like Zeiss above do big Xs for any other pattern.
Don't use microfiber cloths etc as dust is bad stuff. The cloth absorbs some of the bad things, so you want to toss them if at all possible. Hence the cleaning the brush off periodically also. I like Kimwipes. They make a lens-specific one but I am unclear if it's just a different box label as I have used both (even provided at workplaces), and they seem identical.
If you need to get visible ickiness out of the corners, wrap a wipe around a Q-tip, and (starting gently, plenty of liquid) go around the edge of the lens, where stuff gets trapped.
This wiping is going to end like window cleaning. You blow / brush to get all the chunks off, then wipe once to get big dirt, then spray with a bit less liquid, wipe around in circles pretty fast to get all the dirt and residues off, so it's perfectly clean. Should do that visible flash drying you see when good window washing. If spots (large or pinpoints) exist as it dries: it's not clean. Do it again. If it evenly flashes from wet to dry, it's clean.
Emergency, in field, etc. these are my backup. Less optimal, but pretty good and also anti-fog properties so good for eyepro, glasses:
https://www.amazon.com/gp/product/B000GULTY0/
Use them alone, wet+wipe in one but otherwise the same. Leave stuff like q-tip tricks for when you get home, just don't worry about it.
There are likely equivalents, but many of my favorites disappear over time, these seem consistently available.
But, you know, whatever. I haven't really put any thought into this.
(If anyone wants to bookmark, share, etc I did a blog post of this for that reason:
http://centralwargaming.blogspot.com/2022/04/how-to-clean-optics.html)
