◆ PARALLAX

OPSEC for the people who prep AND post on forums. Which is all of you, including the three about to reply that it isn't them.

In your post history you have probably already given away your rough region (weather references, "the local Spar," a sports team), a working inventory of your kit (a tidy list for anyone who ever wants to know what to take), your routine (you post at the same hours, from the same place, predictably), and on at least one bad night, your actual town.

i am not telling you to be paranoid. Paranoia is sloppy. i am telling you to be DELIBERATE. Reread your own last twenty posts as if you were a stranger casing you. Most of you will find your own front door inside ten minutes. Then decide, on purpose, what you are comfortable being known, and post like that from now on. The threat was never a three-letter agency. The threat is being quietly interesting to the wrong neighbour.

I hate that you are right because I make half my living saying "post your checklist so we can improve it." There is a line between method and inventory and I probably blur it too often.

Method: how many gallons per person, how to rotate, what breaks in winter. Inventory: what I personally have on shelf three next to the west window. First one helps the board. Second one helps someone who does not need helping.

I did the last twenty posts thing and found my town in eight. Weather complaint, high school mascot, "our only feed store," and a photo of the back fence with the neighbour's weird garage in it. None of those felt like a disclosure when I typed them.

Not panicking, just feeling very stupid in a productive way.

Radio people are extra bad at this because the hobby rewards precision. Grid square, antenna height, worked so-and-so on five watts from the shed, photo of the mast, lovely sunset behind it. By the time we have finished bragging about the contact we have drawn a treasure map to the coax entry point.

I am not giving up radio logs. I am going to stop putting the shed, the hill, and the neighbour's church spire in the same sentence.

Food-storage version: the pretty shelf photo is worse than a list because it gives scale, brands, container type, sometimes a window, sometimes the kid's school calendar on the wall. I know because I was about to post mine and then saw the calendar in the crop.

I drew boxes instead. The boxes taught the same thing and did not tell strangers what my children eat.

Digital camera note because it keeps coming up: most of your cheap cameras are not embedding a secret satellite fix in 2002. Relax about the movie version. Do worry about timestamps, serial filenames, reflective surfaces, licence plates in the corner, envelopes on the bench, and the fact that you keep saying "the only repeater on the ridge."

The low-tech leaks are doing fine without help.

Apartment people have a different leak: we describe constraints until there is only one building left. Third floor, no balcony, Denver, old radiator heat, grocery two blocks away, laundry room in basement, landlord fixes nothing. That is not a full address but it is uncomfortably shaped like one.

I am going back through my water-plan posts and sanding off the corners.

Good. That feeling is the tool working. Do not turn it into a purge. Deleting everything makes you more memorable and breaks useful threads for everyone else. Edit only what actually exposes a person or a location, and going forward, post method with the corners sanded off.

Useful rule: if a stranger could combine three harmless details into one specific door, one of the details was not harmless.