Here's a flash: Remove batteries from electronic devices if you're storing them between trips.
When I'm not on the road, I keep my compact Nikon flash in my camera bag, and I store the camera bag in my home office.
Although both cameras I use on assignment have pop-up flashes, the lightweight Nikon device lets me bounce flash for softer illumination.
After my last trip in 2014, I stored the flash in its pouch. On my first trip of the year in March, I grabbed the flash, confidently put it in my camera bag and took off, not bothering to check it.
Nothing happened when I turned it on. Assuming the AA batteries were dead, I grabbed two new batteries to insert, opened the flash compartment and found that the old batteries had leaked.
Despite new batteries and a quick cleaning, the flash still didn't fire. When I returned to work, I turned it over to Times photo editor Richard Derk, who cleaned the contacts (with a small screwdriver but "very gently because you don't want to damage those contacts") and restored it to health.
It was a good reminder to remove batteries in any electronic device you'll not be using for a bit.
"All batteries will leak," Derk said, "and humidity doesn't help."
Humidity in L.A.? As rare as it may be, I run a dehumidifier in my home office because that part of the house sits atop a creek that flows (or used to) under the property. In any case, keep electronics away from moisture in any form.