If you spend any time watching low light videos on YouTube, or reading articles by “experts”, you will notice two differing opinions on the requirements of a home defense light. Some will say too many lumens will reflect back into your face and blind you; others say it doesn’t matter and you should go with the brightest possible. So which is it?
I wanted to find out and decided to do some testing of my own – Project Lumen. With this article I will lay out the goal and some ground rules.
The Goal
Can have too many lumens at night? Will too bright a light lead to self-induced blindness? Are the opinions of other based in fact, or just regurgitated internet tripe?
This experiment will hopefully answer those questions while also helping me to determine what the best illumination for my house is. Keep in mind your house may be different. You may have more, or less, shadows; your house is likely a different color and sheen on the interior walls. I have real wood floors throughout my house. If you have carpet the reflected light will be different. You may have mirrors that reflect light. In my house we have a set of French doors leading into what has become the kid’s playroom. Will the light reflected off of those doors be problematic?

Ground Rules
It is worth noting that while I can’t test every flashlight ever made, I have gathered a decent spread of different types and lumen outputs to evaluate. This testing will not be done in a sleep lab or a scientific dark room; no, instead it will be performed in my home, under realistic “bump in the night” conditions. I will get to the actual test procedure in a minute, but certain aspects will be beyond my control; things such as:
- How much moonlight is present through the windows.
- Is there cloud cover?
- Are my neighbors flood lights on or off?
- How well, or how deep, was I sleeping when the test begins?
You may not agree with the results and it is entirely possible that your results would differ from mine. Still, I hope that you take the information and processes used and decide to test your own environment, draw your own conclusions, and ensure the best for your protection.
I want to give a quick note to those that might complain about my methods. I am open to completely redoing the test in a perfectly controlled environment. Just tell me what lab you are paying for and provide me with airfare, per diem, the address, a rental car, lost wages, and the brace of lights you want tested… ‘nuff said.
To make things simple I will use two parameters to define the test flashlights – lumens and bulb type. Lumens is not the “be all, end all” of lighting; but it provides a number that can be used as a reference. Bulb type will allow me to determine if the coloration of the light effects the result (for more on light color and mood click here) on the surrounding environment. I will neither test nor document; run time, durability, candlepower, watts, weight, size or cost. I have also made a conscious decision not to test a weapon mounted light. This test is to determine the effects of light reflection and overall lumens on my eye sight; thus I see no reason to increase the element of error, and danger, by introducing a weapon into the test when I can get the same results with a flashlight.
Definitions
Lumen – : a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle intensity. The Wikipedia page actually has a lot of quality information about lumens for those that want to geek out.
Candlepower – illuminating power expressed in candelas or candles.
The Contestants
Before I get to the test, which is remarkably simple, I want to list the players. I will test one flashlight per night.
- Streamlight TL-3 (incandescent xenon gas-filled pen bulb, 211 lumens)
- Streamlight NF-2 (incandescent xenon gas-filled pen bulb, 78 lumens)
- Streamlight ProTac (C4 LED, 180 lumens)
- Streamlight Micro Stream (C4 LED, 45 lumens)
- Streamlight PolyTac (C4 LED, 275 lumens)
- Nitecore SRT3 (CREE XM-L2 T6 LED, 550 lumens)
- INOVA XS Micro (LED, 80 lumens)
- NEBO Classic (LED, about 100 lumens)
- Mag Light – 3 D Cell (incandescent, around 45 lumens)
- A borrowed Streamlight Stinger DS LED (C4 LED, 350 Lumens)
- Maybe a Q-Beam if I can borrow one (Bright!)
The Test
For as long as this article has become, the test is actually pretty easy. I will stage one flashlight on my bedside table at bedtime. I wake up at 5:00 AM, well before anyone else in my house; so, when my alarm goes off, I will simply proceed to “clear” my house. I will take the same path during each test. With nine flashlights and the potential for more this will take a couple of weeks, but my goal is to update what I learn as I go and offer a final conclusion at the end.
The test begins tonight.











