Broncolor announced two battery-powered strobes today. Coming in 400-joule and 800-joule variants, offering flash durations of as little as 1/19,000s, and in a similar power option, the new Siros L strobes are clearly aimed at the 500-watt Profoto B1 with nearly identical features in all but one area, depending on what's most important to you.
For those that don't remember their high school physics classes, you can change out "joules" (or, more accurately, "joules/second") for "watts" (or, more accurately, "watt-seconds") -- the unit of choice for measuring most flash systems' power. In this case, Broncolor has two options, increasing the maximum, high-end, battery-powered strobe wattage to 800 Ws for those that need all the power they can get outdoors or elsewhere in the field. You'll trade that power for size, weight, and battery life when you notice the 800 J Siros L is 1.5 in. longer, 1.5 lbs heavier, and features half the battery life compared to the 400 J's 440 full-power flashes. The good news is that this is because, as you may have guessed, the Siros L units conveniently use the same battery.
Overall, the Siros L is generously appointed for its class (though that distinction has yet to hold based on the still unreleased price of the units). The 800 J still features as many full-power pops as Profoto's "only" 500-Ws B1 and manages to maintain a relatively streamlined form in comparison to the B1's slightly odd battery bulge. The batteries also charge in 70 or 75 minutes depending on what literature you read, which is a hair over Profoto's one-hour charge time with the optional quick charger, but nearly twice as fast as with their included charger.
Both models feature full compatibility with each respective company's lighting modifiers and wireless technologies, but Broncolor adds a nice touch with their multi-color LED identifiers that help tell each unit apart when adjusting them from Broncolor's lighting control app.
Profoto and Broncolor continue this dance around features throughout the multitude of considerations any photographer would make. For those who hand-hold their strobes on occasion, every pound counts. That's where Profoto's 6.1-pound battery-included weight will be preferable compared to the 400 J's more than eight pounds and the 800 J's 9.5 pounds of heft, despite all of the units being very close in overall size. The 500-Ws B1 offers slightly more power than the 400 J, but only half the battery performance. Meanwhile, the 800 J offers a healthy increase in power in exchange for dropping to "just" 220 full-power flash pops -- identical to the life the B1 will show. So you may have to make a choice between weight and battery life.
But when you begin looking into other features, the lack of mention of high-speed flash sync in any of Broncolor's literature is slightly alarming for those shooting at large apertures or in broad daylight, for which the 800 J is obviously specifically built. I'm hoping this is an oversight of the marketing department rather than the engineering department.
The Siros L units will be available July 2016, but without word on U.S. pricing, it's still hard to make a definitive statement or judgment with respect to which model wins out on paper. Thankfully, we know that the price in Switzerland will be 1,998 CHF for the 400 J and 2,349 CHF for the 800 J, which figures very closely to the U.S. dollar.
The 400 J and 800 J strobes are now available for pre-order from B&H for $2,053.10 and $2,347.10, respectively, with an estimated ship date of July 10th. For just about twice the price, you can get a kit with two lights each, a softbox with adapter ring, a silver/black umbrella, two batteries, a single charger, and a backpack to hold it all. That kit comes is available for boht the 400 J and 800 J models.