this post was submitted on 29 Mar 2026
3 points (100.0% liked)

flashlight

3369 readers
1 users here now

Portable illumination

Rules:

  1. Be excellent to each other
  2. Don't be the reason we need to make more rules

Related:

founded 2 years ago
MODERATORS
 

I wonder if someone here with suitable test equipment could run a graph on a chemical glowstick, the ordinary 12 hour kind, not a special fancy one. I'm basically hoping for a rough estimate of the lumen output and its decay over time. I did a bit of web search and got drastically varying numbers. I guess I could make an eyeball estimate, but would want to use a reflector of some kind for the ceiling bounce.

Does anyone know if reflectors like the below are still being made? Of course I can DIY one if necessary. Web search didn't find anything quickly, but it's difficult to keep the results relevant.

https://www.worthpoint.com/worthopedia/nos-vintage-glow-stick-lantern-1960s-4706797024

I'm quite dubious of chemical light in this day and age, but they come up in discussions sometimes, so I'm interested in a concrete comparison against flashlights. Thanks!

Added: I'm happy to reimburse the cost of a few glowsticks if you're up for running this test. Or it's possible that I could order some and have them sent to you (Home Despot free delivery). PM if you want this.

you are viewing a single comment's thread
view the rest of the comments
[–] solrize@lemmy.ml 0 points 1 week ago (1 children)

That looks like AI output and no there's no need to test thousands. Testing just one that acted fairly typical would be good enough to get an indication. Testing a handful would show if there's much variation. Folklore has always been n=30 is usually good enough to observe the normal distribution, though that's not so reliable really.

https://statswithcats.net/2010/07/11/30-samples-standard-suggestion-or-superstition/

[–] dr_jekell@lemmy.world 1 points 1 week ago* (last edited 1 week ago) (1 children)

Gee thanks for calling me an AI.

But nope it's just things that I noticed (checks calendar) a long while back when I was looking at getting a bunch for my emergency kit.

I decided against buying them as they are an order of magnitude more fragile than an LED light, no guarantee that they will work when you need them and a ~4 years of shelf life compared to ~10 years for lithium batteries.

Modern LED lights can offer days and even months of runtime on a battery set, multiple light output levels and when paired with a lantern cap accessory or a cone of printer paper provides the same functionality as a glow stick while being far more versatile.

Plus combining several sets of rechargeable batteries, solar panels and charger you have consistent lighting for at home and having the option of keeping lithium batteries in your evac kit.

[–] solrize@lemmy.ml 1 points 1 week ago* (last edited 1 week ago)

The merits of lightsticks versus LED's weren't part of my question. I just wanted a measurement, not purchasing advice. The idea that a single measurement is uninformative and that I really need thousands of measurements is ridiculous. It seemed like something an AI would say, but ok I guess a human could say it carelessly. If I thought a single measurement was suspect, I'd go for maybe 3 measurements. People infer all the time from way less than thousands of observations.

As for fragility, one suggested way to use a light stick is to put it at the end of a few feet of cord and swing it around in a circle, for more visibility from a distance. Most people won't want to do that with LED lights.