The main features to look for in a battery-powered monolight are output, recycling time, output range, number of pops per charge, modeling light power, types and sizes of modifiers, size and weight, and price. Monolights tend to be less powerful than studio strobe power packs and heads, but the improved ISO capabilities of modern DSLRs are mitigating that power differential. At the same time, monolights give you access to all of the sophisticated modifiers of a studio strobe outfit.
Output. More powerful units give you more options for depth of field (you can shoot at smaller apertures), light placement (you can place lights farther away if you have to, as for outdoor sports action) and use of light modifiers like umbrellas, which reduce intensity. Some units are rated in watt-seconds (W-s), others in joules; one joule equals one watt-second. Note that joules and watt-seconds are measures of generator power, not necessarily light output; output also depends on the flash head and any light modifiers used.
Guide numbers aren’t really useful for pro flash because they’re based on point-like light sources that follow the inverse-square law (double the flash-to-subject distance and quarter the light, triple the distance and get one-ninth the light, etc.), like shoe-mount flash units. Pro units are generally used at close range and/or with umbrellas or other light modifiers that increase the size of the light source relative to the size of the subject, where the inverse-square law isn’t a useful measuring stick. Some pro-gear manufacturers include the tested ƒ-stop for a flash head (or head with specific light modifier) at a specific distance, which can be a useful comparison measure if another manufacturer provides the same data for its units.
Output Range. Monolights can also be operated at a range of power settings. This is helpful not only when you want to control light output, but to control flash duration (lower power generally means shorter duration), battery life (full-power bursts take more out of the battery than lower-powered flash) and recycle times (the flash will recycle more quickly at lower power settings). Because they’re self-contained, you can adjust the power of each unit separately in a multiple-light setup for easy control of lighting ratios. Color temperature can change with power setting, although with today’s units, this generally isn’t a big problem.
Pops Per Charge. Battery power is a critical limiting factor. When comparing potential purchases, note how many full-power flashes the unit can produce on a full battery charge. Also check into the cost of extra batteries and how long it takes to charge them fully.
Location Lighting Masters
|Crafting the light for a photo is an art, and it’s also an exercise in puzzle-solving. Two photographers you should follow to learn both the art and the puzzle-solving sides are David Hobby and Joe McNally. Hobby is the founder of the popular Strobist blog, and McNally is widely known as one of the most innovative location lighting masters in the world. As much as we focus on the light head in this article, it’s knowing how to manipulate the light that really creates the style, look, mood and emotion in the photo. David Hobby’s Strobist blog is at www.strobist.blogspot.com, and Joe McNally’s website is at www.joemcnally.com.|
Recycling Time. Recycling time depends mainly on the power output used, and the size and state of the battery. You want to look for recycling time to full power after a full-power burst. Note that recycle times will increase as the battery charge runs down, and that recycling times on battery power are generally slower than on AC power for units that can use both power sources.
Modeling Light Power. Modeling lights give you a good idea of how the light will fall on your subject. A lot of photographers have come to rely on modeling lights because they make the process of lighting close to WYSIWYG. With AC-powered flash units, modeling lights aren’t a big problem. But with battery-powered units, they add significantly to the power drain. Therefore, one needs to be more judicious with the modeling light and be aware that, in some cases, battery-powered monolights don’t call for modeling light usage at all.
Light Modifiers. One of the big advantages of studio-type flash is the range of excellent light modifiers available—parabolic reflectors, umbrellas, light boxes, snoots, grids, beauty dishes, barn doors and more. Many units accept standard “S” modifiers. This is one of the most important advantages monolights have over smaller, hot-shoe-type flashes. Although the overall power output is less than a studio strobe pack and head outfit, you can use most, if not all, of the same modifiers. Check to see what’s offered for each unit you’re considering to make sure what you need is available.
Size. Portable means you’re going to be carrying it so consider dimensions and weight. Battery-powered monolights are more portable than studio strobe packs and heads, and they’re more bulky than shoe-mount flash units. Everything in life is a trade-off, and when it comes to portablility, monolights aren’t perfect, but the trade-off is attractive for many location photographers, in particular.
Price. Higher-end monolights generally cost more than shoe-mount flash units, low-end monolights less than high-end shoe-mount units. You have to weigh the benefits versus the cost, as with everything in photography. Monolights can do things shoe-mount flash can’t; if you need those features, you need a monolight.
Profoto’s battery-powered monolight is the B1 500 AirTTL, a self-contained cordless model with an onboard, exchangeable, integrated, lithium-ion battery, so you don’t have two pieces to deal with. The unit also offers TTL exposure control with Canon DSLRs (Nikon compatibility is expected in 2014). Just plug the Air Remote TTL unit to your camera’s hot-shoe, and the off-camera B1 unit will automatically adjust its output for correct exposure. Power can be adjusted from 2 to 500 W-s in 1/10-stop increments (a nine-stop range), recycling
times range from 0.1 to 1.9 seconds (the unit can fire up to 20 bursts per second at lower power settings), and durations can be as brief as 1/19,000 in Freeze mode.
Powerpack & Lighthead Options
|While this article has focused on the benefits of monolights that can use a battery pack or plug into the wall, there are also battery-powered studio strobe-type units available. These tend to be very powerful and give you maximum flexibility/control and all of the advantages of a large studio system. On the downside, these systems are heavy, bulky and costly. If you need maximum power and you need it without being connected to an AC outlet or a portable generator, a battery-powered studio strobe pack and heads is the answer. In this category are such systems as the Broncolor Move 1200, Elinchrom Ranger RX, RX Speed AS and Quadra RX, Hensel Porty L and Premium Plus, Paul C. Buff Zeus, and Profoto Acute B2, Pro-B3 AirS and Pro-B4.|
Paul C. Buff
Paul C. Buff offers a number of monolights that can be plugged into AC or used with the Vagabond Mini Lithium, a third-generation, true sine wave current-limited portable power system.
Einstein E640 has a built-in fan and microSD slot for firmware upgrades. Four AlienBees units (160, 320 and 640 W-s, and a 320 W-s ringflash) offer power settings from full to 1/32. Three White Lightning units (330, 660 and 1,320 W-s) offer dual power, high adjustable from full to 1/32 and low from 1/4 to 1/128. All offer quick recycling and built-in slave triggers. The Vagabond pack weighs just 3.5 pounds, but can operate up to four Paul C. Buff monolights (there are two outlets, but you can use a power strip to connect up to four heads). The quick-connect, rechargeable lithium battery provides 200 to 250 full-power flashes with 1,280 W-s of heads connected, 800 to 900 flashes per charge with 320 W-s. The Vagabond Mini can power all the above-mentioned monolights.
Interfit’s Stellar Xtreme AC/DC Monolights are 300 W-s units. They have built-in slave sensors for flash and IR, modeling lamps and user-changeable flash tubes. Recycling time on AC is 2 seconds to full power, on battery power, 3 to 10 seconds. Power is adjustable from full to 1/16 in 1/10-stop increments. The units include cooling fans. A full battery charge with the Mark II battery provides about 200 full-power flashes.
Broncolor makes AC-powered monolights. We’ve included them here in an article about battery-powered monolights because the company also offers a battery-powered inverter that works with the mobile Broncolor monolights. Broncolor offers six AC-powered Minicom monolights (300, 600 and 1200 J, with or without RFS radio control from a computer with eight-channel RFS interface). All can also be powered (up to 900 W-s worth) by the Power Box 900/W Battery Power Supply, which is a stand-alone inverter power supply. The Power Box can also handle modeling lamps up to 450 watts. With a single 300 W-s monolight, it can provide 240 full-power flashes. The Minicom monolights are available from 300 to 1,200 joules, with built-in photocell, IR receiver, and in RFS 2 units, radio remote control. The monolights can also be powered (up to 900 W-s worth) by the Power Box 900/W Charger, a stand-alone inverter power supply.
Visatec makes several AC-powered monolights that can be plugged into the Broncolor Power Box 900/W. The Power Box 900/W is an inverter with a lead battery that converts its DC battery power to AC. Three of Visatec’s four Solo monolights (400 B, 800 B and 1600 B) and all five Visatec Logos monolights (800, 800 BC, 800 RFS, 1600 and 1600 RFS) are compatible with the Power Box 900/W. The RFS units feature RFS radio control.
Featuring exchangeable lithium-ion batteries built into the back of the lights, Priolite’s MBX500 and MBX1000 provide studio control and power without cords or external battery packs. With the power of 10 to 20 speedlights packed into one unit, the MBX have sufficient output for use on location on sunny days. Both units feature a quick duration of 1/4500 at full power, modeling lights, optical slaves and bidirectional radio controls.
Hensel offers monolights that can be operated with AC or battery power. The Expert D (500 and 1,000 W-s) features built-in radio receivers (Hensel Freemask Wizard or Hensel Strobe Wizard, both 3-channel, or Profoto Air receiver, 16-channel). The Integra Plus FM units (250, 500 and 1,000 W-s) incorporate a Freemask Strobe Wizard radio transmitter and Freemask (part of the Hensel hardware), which allows the photographer to take two shots on a white seamless and drop in any background. The first shot is a normally lit foreground image and the other is a silhouetted background image that allows for easy masking in Photoshop. This eliminates the need for bluescreens or greenscreens and the problems they cause. The compact Integra Mini units come in 300 and 500 W-s versions; the Speed Max can deliver flash durations as brief as 1/66,660 seconds and up to 31 flashes per second. All can be powered (up to 2,000 W-s max) by the company’s two-socket Power Max L mobile power supply, which can deliver up to 880 flashes at 250 W-s, 440 flashes at 500 W-s. The Power Max L can also be used to power the company’s continuous lights.
Bowens offers six Gemini monolights, from 400 to 1,500 W-s, which can be powered by AC or the Bowens Travelpak. The Gemini 400Rx has a built-in Pulsar radio receiver; the others have a slot for a Pulsar receiver card. The units are ruggedly built, and have either a 5- or 7-stop range and bright modeling lights starting at 250 watts. The 500R features a digital readout with two dials for quick independent control over full stops and tenths of a stop. The Pro models also incorporate a cooling fan, and faster recycle and flash duration. The Travelpak comes in Small and Large versions. Both provide 400 to 1,500 W-s output and recycling in 4 to 15 seconds; the Small provides 50 to 185 full-power pops per charge; the Large, 100 to 370. Each can power up to two Gemini heads.
Dynalite’s Uni400JRg monolight can be powered by AC or with the compact Dynalite Jackrabbit II battery. With the Jackrabbit II battery, the Uni400JRg can deliver up to 150 full-power (320 W-s) flashes with a 4-second recycling time. It can also be plugged directly into AC power, with 1.4-second recycling and 400 W-s output. You can adjust power from full to 1/8 in 1/3-stop increments. Dynalite also offers the XP800 pure sine wave inverter with three AC power outlets for flash heads and three USB ports for electronic devices.
Photogenic’s compact Studiomax III AKC-160B (160 W-s), AKC-320B (320 W-s) and AKC-320BR (320 W-s, with built-in radio remote receiver) can operate on AC or battery with the optional AKB-1 battery pack, which provides up to 150 full-power flashes per charge.
The Flashpoint 180 Battery Powered Monolight uses two NP-F960 batteries to provide up to 700 full-power (180 W-s) flashes per charge. The under-$200 kit includes the monolight, reflector, small umbrella, two batteries and charger, cords and carrying bag. The Flashpoint M-series monolights can be powered by AC or DC (battery), and the Flashpoint 320M, 620M and 1220M (150, 300 and 600 W-s, respectively) feature low-cost, proportional modeling lights, built-in slaves and fan cooling. The DG400 (200 W-s) and DG600 (300 W-s) have cool LED modeling lights and digital readouts.
JTL’s Mobilight DC-600 (600 W-s) and DC-1000 (1000 W-s) monolights operate off a proprietary rechargeable battery, providing up to 500 full-power flashes with the DC-600 and up to 260 with the DC-1000. Both have a built-in photo slave and 360° universal radio receiver for wireless remote control.
|The dramatic rise in the number of photographers who are also engaged in motion capture has created a lot of interest in continuous lights for still and motion. Continuous units let you see the actual lighting (electronic flash units’ modeling lamps just give an approximation), but they don’t have the action-stopping ability of a flash or strobe. Most reasonable portable continuous lights are less powerful than strobe monolights, and incandescent continuous lights are hot (LED and fluorescent lights are much cooler and more energy-efficient). Some photographers prefer continuous lights for their ability to create a feeling of warmth in an image. This is highly subjective, but strobes have always been characterized as creating a sterile look, and as continuous lights have become more portable, powerful and cost-effective, they’re certainly worth a look.|