There are many practical assessments that fall into this product category. One of the main reasons for this is the lamps themselves. It is difficult, if not impossible, to use product specifications or photos to get a feel for how durable you can expect the bulbs to be. Sometimes you'll get lucky with a “shatterproof” tag in the description, but not always.
Another aspect of the bulb to consider is the physical connection. Some of them are pre-installed and you cannot replace them yourself. Some are pre-installed and can be removed. Most bulbs, in my experience, come separately packaged for you to install yourself. Most of the time this is not a problem. Occasionally, because these products all try to have a watertight seal, the bulbs can be difficult to install. Several times I found myself grabbing and twisting the small bulbs hard enough that I worried they might break in my hands. No one has, but it might be worth having a pair of gloves on hand if you find yourself in the same situation.
Approaching our brightness tests. The meter is at some distance from the unit under test. Rotate and manipulate the product until you find the maximum brightness value. It's hard to take pictures in the dark without help!
In general, the main concern with most lights is how much light they put out. In the past, for some of our standard lamp testing, we used an integrated sphere. That type of equipment can give you a ton of information about a light source, including brightness in lumens, color rendering index, and more. Read more about our lamp testing laboratory.
For this category, I was specifically interested in brightness. Unfortunately, these string lights can't be tested in our integrated sphere, but with some fancy math magic, I changed the calculations we needed from a sphere to a linear path and came up with a workable solution. Using a standard digital light meterI was able to get the approximate light output of each bulb in lumens.
Brightness chart for solar and battery powered outdoor string lights.
Looking at the chart above, you can see the brightness of an individual bulb from each string, as well as the total brightness of the entire string from the solar and battery options. Real Living's light bulbs were dimmed. Hampton Bay has the brightest individual bulb, while Coleman says the brightest strand in this series overall due to the greater number of bulbs.
In the AC power options shown below, Brighttech carries the brightest individual bulb at around 196 lumens. Multiply that by 15 bulbs and you get nearly 3,000 lumens. Magitec wins the brightest overall with 30 bulbs at 165 lumens, for a total of nearly 5,000 lumens. To be fair, Magitec offers two filaments for the price of one, so an individual filament would be around 2,500 lumens; about 500 less than a Brightec string.
Illumination of external AC string lights.