One of the biggest problems with comparing lighting systems is that there are endless variables to compare. If you are looking for a good strobe for studio or outdoor work, this video has a lot of information to give you a concise look at which one might be best for you.
Rob Hall has some of the most well-researched and objective light comparison videos. In this video, which is the first in a series of comparing Westcott and Godox lights, he looks at the Westcott FJ400 and Godox AD400Pro, two popular entry-level 400 Ws strobes. One common misconception with strobes is that watt-seconds is a measure of power output. Watt-seconds is the most common unit used to categorize strobes by power output; however, it is a unit of power consumed and not power output. Some strobes consume power more efficiently to produce brighter light with less power. Using a light meter to test the output between the two 400 Ws strobes, Hall found that the Westcott strobe was actually 40% more powerful than the Godox equivalent. The Westcott light shows more variation in color stability with a greater shift in color temperature over time than the Godox light. In total, Hall looks at about 20 different characteristics that are bookmarked in the description of the video for easy reference. He also provides a spreadsheet with all of the data he measured during the tests.
With so many biased reviews and skewed ways of looking at data, it’s nice to have a review that looks at so many factors using objective data. The bottom line is that, depending on how you shoot, one strobe might be better for one person, but not necessarily for you. Here, Hall not only compares the strobes in several categories but also explains who would find each light more useful. Check out the video for the full explanation.