When hot shoe flash just doesn't have enough oomph, photographers go to studio strobes.  The challenge with strobes has always been availability of power.  Most major strobe vendors have developed high output battery pack systems so AC is not always required, but these packs have been in most cases heavy and expensive.  Profoto released the self-contained B1 series a while back and they have been very successful.  Now available is the B2 system which uses an external generator pushing 250ws.  It's a bit pricey so let's see what makes it a great choice.

Introducing the B2

More recently manufacturers understood that photographers also wanted portable strobes that were light in weight as well as capable of running on battery.  Elinchrom did a terrific job with their Quadra lineup with very small capable heads running off an asymmetric battery pack with 400ws capability.  The only downside was that to use standard Elinchrom light modifiers you needed a separate bracket system as in getting to low weight, the Quadra heads don't have modifier mounts, and the heads themselves have fairly flimsy mount systems.  Profoto now competes in this space, albeit at a significantly higher cost of acquisition with the new B2 system.

The Profoto B2 system is the second release in Profoto's OCF or Off Camera Flash offering.  The family is characterized by being powered by batteries, being lightweight and portable, but still capable of using all of Profoto's industry leading light shaping tools.  Profoto will NEVER be the lowest priced kit in the room, but if you are travelling and need to rent additional kit, every serious rental house has LOTS of Profoto gear available.

Like the B1 system, the B2 system is a modular approach.  In the B2 system, you have up to two heads per generator and you can run the heads like traditional mono strobes or with the additional AirTTL controller for Canon or Nikon get full TTL flash control at strobe level power.  

I've been a B1 customer since shortly after release and have found the strobes to be excellent.  The light quality is superlative, the colour is consistent and the modifiers go on and off with great simplicity.  The B1 heads have a self contained rechargeable battery and can push 500ws at full power.  My B1 kit came in a backpack and the heads mount to any standard ⅝ stand mount.  The AirTTL is a great bonus and offers both High Speed Sync and Second Curtain Sync, something Canon doesn't even do with its own lineup.  

Some photographers and instructors poo poo TTL flash at all times.  I know that there is a time and a place for TTL and when it's that time it gets you to the shooting quickly without problems.  Having both is a real asset.  I wish my Profoto D1 heads had TTL capability, Profoto has done such a good job in the B1s.  The B2 heads are considerably smaller, because the battery pack and generator are a separate, but still small unit.  This means perhaps even more agility for the head placement, so long as you are within cable range because of course you have to connect the head to the generator.  That the system is so lightweight and has about 5x the power capability of a good hot shoe flash, plus TTL when used with the AirTTL controller makes it very usable quickly.  The added power over most hot shoe flashes means that you can still use smaller apertures because the flash can keep up you and with wider apertures you get more range, useful when using the units for fill in outdoor group shot situations such as a wedding or family picnic shoot.

The AirTTL system lets you control the heads right from the camera hotshoe.  The display is clear and easily read with three separate zones and the ability to regulate output by zone.  So with a two head system, you can easily set a key and fill light at a pleasing ratio and manipulate your settings in real time right from the camera, no running from head to head.  This works whether you are in TTL or Manual mode so the advantage is complete.

When I first was advised by Profoto of the coming system I was very excited because the B2 heads would work completely in sync with the B1 heads from the same AirTTL controller.  Then I read that the output was 250ws.  Compared to hot shoe flash, that's a lot more power, especially when using light shapers that may consume some of that power in doing their shaping jobs.  But it's less than the 400ws I get out of the Elinchrom Quadras I already owned and they are a proven reliable system with a great radio system as well.  The only thing that the Elinchroms don't do is TTL.  And the Quadras use the same radio as the BRX heads that I also have.  How does one justify the significant price jump from Elinchrom to Profoto?

I think that the decision starts with where your current investment is.  If you have bought into the Profoto lineup of flash units, and light shapers, and you need a small light battery option, the B2 is the way to go.  If you are just looking at getting started with battery powered strobes, the Profoto kit is top notch but enter the game knowing going in that it's going to cost you more than Bowens or Elinchrom options.

Real World Testing

I was very excited when the evaluation kit arrived.  I had downloaded the manual and read it several times.  Easy enough, it's quite short.  Like my other Profoto experiences, the UI (user interface) is excellent and the units are designed to get you working quickly.  I unpacked everything carefully saving every bag and twist tie and charged one of the two batteries.  After a quick scan of the manual, I mounted the battery, connected a head to the first output and powered it up.  I was positioning the head on the light stand when I heard some clicks and turning watched the generator jitter.  Then there was one hell of a pop and smoke erupted.  I've been a musician and worked around amplifiers for years.  I knew that smell.  One significant capacitor had just committed suicide.  

Well now I'm pretty underwhelmed.  I sent an email to the Manager at my dealer and met him the next morning with everything packed up and a nice clear description of what went wrong.  Chris is a complete professional and took the Location Kit back from me and set to finding me another one.  He was successful and I was pleased to receive round two just two business days later.  This is expensive gear and I was impressed by the turnaround.  Any manufacturer can have a DOA.  I got past my initial frustration and went through the same process, unpacking carefully, charging a battery and getting things set up.  This time I positioned the head first, connected the cable, attached the now charged battery and powered up the generator.  Nice OLED display lights up, and the unit is dead quiet.  I put my Air Remote from the D1 kit on the shoe of an evaluation Nikon D810 and shot a couple of frames.  Good guess on the initial settings, all is good, recycling is lightning quick and I've shot a number of quick frames of Sondra in no time.

The generator and battery are lighter than the comparable units of my Elinchrom Quadras.  The Quadra pushes more power so this can be expected.  The generator and battery fit nicely into an included carry pack that has belt loops, a grab handle and connections for a shoulder strap.  The case is nylon with holes fitted to allow charging the battery while mounted and if needed, to connect a wired sync cable.  The case also has two large ventilation ports.   Like all my other Profoto gear, the designers clearly understand user interface.  There are two locking connectors for heads, with spring loaded covers (nothing to remove and lose), a visible slave cell, and a large easy to read OLED display with three buttons below it.  They set your sync option, offer a SET function for programming settings and an on/off button.  To the right of the display are four buttons.  They offer settings for modelling lights (on/off) with one for each connection, a mode button for selecting between Normal and Freeze (short duration) mode and Ready settings for Dim and Beep.  The display has a nice large graphic of the state of battery charge.  Once you lock a head cable in place, the display will show you the power setting for the head.  The control for output is a click stop rotary dial and in another indicator of smart design, the dials are shielded by a rubber overhang on the generator to prevent undesired settings changes.

The B2 heads are as noted 250ws capable heads with Profoto's proven diffusion plate up front similar to the ones on B1 and D1 heads.  The light from them is as beautiful as expected.  Each head also includes LED modelling lights that have output equivalent to a 50w halogen but without the power consumption or heat generation.  Each head comes hard wired with a cable, that looks to be about 1.5m long.  I find that too short in general although it keeps the units small for transportation.  For that reason, I ordered the optional 3m extension cable to use with the second light so I could get reasonable separation between them.   Each B2 head takes all of Profoto's new OCF modifiers and you can mount pretty much any of Profoto's light shapers to the heads.  The mounts are very solid and go on a standard 5/8 stud.  The difference in mount quality and durability along with no need for a mount enhancement option makes the B2s more widely usable than the Elinchrom Quadras.

Each head fits into a padded case that has it's own space in the included go bag, that in addition to two heads, holds the cables, two batteries, the charger and its cord.  The go bag is padded and zips up snug.  Too snug in my mind as I would like to be able to put the 3m extension and either the Air Remote or Air TTL Remote in there with them.  The go bag fits inside an unpadded cordura location kit with a bit more room and some straps for light stands and small modifiers which is very handy.

The ability to hit the road with lots of power (each head has the output of four to five speedlights) in a light kit is great.  I don't have to worry about humping C stands and booms around.  I keep a pair of Manfrotto 420B boom stands for field work with the B1s and while they are a bit overkill for the B2s, they work perfectly.  When the B2s were announced, Profoto also announced the OCF lineup of light shapers.  They are designed to be lighter and less expensive than Profoto's standard accessories.  With the exception of the OCF Speedring it's true, that Speedring actually sells for more than the regular Speedring despite being made of plastic instead of metal.  Go figure.  To see what this lineup would be like, and because all the OCF stuff also work on B1 and D1 heads, I ordered up a grid kit, a snoot and the 2' Octa along with the Speedring.  The stuff just works.  Assembling the small Octa is no problem and the rods hold it open without requiring a Kryptonian to bend them for assembly.  The B2 heads have notches in their front ring making using the Snoot and the Grid kit easier to mount on the B2s over the B1s. The Speedring mounts fast with the same rubber ring clamp as the rest of the Profoto series so no fighting with recalcitrant bayonet mounts at odd angles.  I had modified some clone Profoto inserts to allow me to use Lastolite Ezyboxes on my B1s and D1s and they mounted perfectly to the B2 head.

Profoto has a couple of videos showing the B2 mounted on an erector set looking flash bracket attached to the camera.  It's actually from ProMediaGear and is called the Boomerang.  So you can put a B2 head on your camera.  I did copy what I saw Joe McNally do, which is mount the B2 on my modified Shurline paint pole with the small Octa and working with camera on tripod was able to get some very nice tests done with only myself on the photographic side.  I later took this into the field for some client work and it was lightweight and very effective.  

The more I thought about using the B2 head like a hotshoe flash, the more curious I became.  Certainly the initial feedback I had seen was along the lines of "WTF?" and when I saw the price of the Boomerang mounting system that Profoto was using in their ads, I had to wonder some more.  Then I had a project that would benefit from B2 power in a supplemental light / fast moving role.  I needed to fight sunlight and couldn't be encumbered by even a simple light stand.  So I used a spud on a RRS foot to mount the B2 head to my RRS Wedding Pro Flash bracket.  The generator went across my body like a sling, the camera with 70-200 slung the other way, and I could work quickly moving easily with 250ws of available flash power in TTL mode for fill on one of those beautiful harsh shadowed sunny days that regular folks love and make photographers worry about the light.

In addition to shooting from the D810 in manual mode, I used my Air TTL C remote on my Canons to see how the B2 kit worked in TTL mode.  Canon's own TTL controller for off camera flash should work this well.  HSS (high speed sync) is supported so excellent for supplementing daylight in bright conditions.  There is no mention of second curtain sync support as is found in the B1 units but on using the Air TTL Remote on my 1Dx for a quick test I was able to get second curtain sync to engage on the remote and fire the main flash on curtain close.  Metering flash is plainly visible on first curtain but the exposing flash was happening on close so that's good news.  Profoto rates the B2 generator / battery at 215 full power flashes on a charge.  Pushing the unit hard for some tests, this seems like a reasonable advertisement.

It should be noted that the generator drives two heads, and each head can be assigned to it's own group.  Profoto supports groups A-F but only A-C are TTL capable. The generator and remote are pairable on any of eight distinct signalling channels.  When shooting in TTL with one head in A and the second head in B, you can control your lighting ratio by simply manipulating the Flash power settings for each group.  This makes getting pleasing ratios very simple and all doable from the camera attached Air TTL Remote.  I'm looking forward to doing some outdoor fill flash work with two groups.  Unlike the B1 and D1 heads, the modelling lights are always full power with no variable output option.  They can be configured to go off when the flash fires and stay off until it is ready to go again.  There is also a timer function setting in the generator to turn the modelling lights off automatically to preserve battery power.

I did find myself unable to mount the AirTTL-C controller to the hot shoe on my Hasselblad H4D-40, it just would not slide into the shoe.  I have the regular Air controller that came with the D1s and it mounted fine and controlled the B2s in manual mode without issue.  I used that "B2 on RRS bracket" system again with the 'Blad and it worked fine in manual mode needing only a couple of test exposures to get settings right, and delivered enough power to handle higher shutter speed as a fill flash with a wider aperture in bright sunlight.

Conclusions

We won't kid each other.  The Profoto B2 system is excellent.  It's also very expensive and probably outside the price range of the general photographer.  That said, as I noted earlier, if you've already bought in to Profoto, and you need small battery powered strobes that will blow hot shoe flashes into the dust, and you want TTL for your Canon or Nikon, this is the way to go.  If TTL is not in your requirements list, you may be overbuying given the Elinchrom Quadra alternatives.  The folks at Phottix even have their own Indra500 battery pack driven 500ws strobe that does TTL so long as you get an ODIN transmitter.  Both will cost you less than the Profoto B2 system.  But, I love the simplicity, the efficiency, the light shapers and the quality of light that I get with Profoto.  That second B2 Location Kit for eval never went back and it made a dent in the budget, but it serves my use cases with aplomb.  Where I live in Canada, you can find a B2 To Go kit with a single head for about $2630 and a B2 Location Kit with two heads and two batteries for around $3530.  AirTTL controllers run about $560.  Serious coin, but serious lights.