Recommended Big Light: Paul C. Buff Einstein e640

UPDATE, 1/1/2019: Nine years after its introduction, The Paul C. Buff Einstein e640 is still the best bang-for-buck monobloc in the world.

If you shoot small lights long enough, you will run up against some limitations. You might be trying to light big areas, or trying to get a combo of soft light with a large working distance. More likely, you might be trying to light against full sun. Or maybe some combination of the above.

Suffice to say that at some point you might want a big gun in your lighting bag. But choosing from the blistering array of options in the studio flash marketplace can be a daunting thing.

My recommendation, for photographers living and working in the U.S., is to buy a Paul C. Buff Einstein e640 monobloc flash. Here's why.

Oodles of Power

The Einstein ($499 factory direct) has 640 watt-seconds of power, about eleven times as much as a typical speedlight. That number can be deceiving, as all things being equal you actually only gain one f-stop of light for every doubling of the power level. But 600-800WS is a sweet spot for all but the most demanding subjects.

The group shot above (more detail on that shoot here) was key-lit to f/8 at ISO 200 with a battery-powered Einstein on half power. And that flash was reflecting off of a 60" white-backed umbrella, then going through a diffuser. So yep, plenty of power.

Just as important, the lights can dial down in power (in increments of 1/10th of an f-stop) to less than the equivalent of power of a single speedlight at 1/16th power. That's amazing, and is a feature I find super useful on a regular basis.


Einsteins can be plugged into the wall or powered by the company's $239 Vagabond Mini Lithium battery (sold separately). This takes the flash from being a studio light to an anywhere light.

The battery is well-designed (I have five of them) and delivers power through a 120v/60hz standard outlet. Which means it also can be used in a pinch to power other items or charge your phone when off the grid, or during a power outage.

Pulse Speed and Color Consistency

There are two qualities of a studio-style strobe which are not physically apparent, but are very important. These two features are pulse time, AKA "t.1 time," and color consistency. The Einstein employs a clever and unique solution to both that allows it to punch way above its pay grade.

The t.1 time of a flash is the all-in (okay, technically 90% in) time measurement of a flash pulse. In other words, how long does it take your flash to produce all of that light?

There is also a confusing (but much more flattering) measurement of a flash pulse called a t.5 time. That's the length of time it takes for a flash to delivery half of its light energy. (More info on understanding those measurements, here.)

Suffice to say that a the energy pulse of a flash ramps very quickly, but dissipates in a "long-tail" graph. So if the flash you are manufacturing has a crappy pulse time, you're probably gonna sweep that design flaw under the rug by quoting the t.5 time of your flash rather than the t.1 time — if you quote a time at all.

Put differently, the t.5 time is a bullshit, near-useless measurement quoted by flash manufacturers when they have designed a flash with a crappy t.1 pulse time. No lie: I have seen flash-pulse times of slower than 1/100th of a second. Not so great for stopping action without ghosting. Or even trying to balance against sunlight at a shutter speed of 1/250th of a second.

So that's one's quality. The other quality is color consistency.

For obvious reasons, you want the color consistency to be as tight as possible across the entire power range. This is especially true if you are shooting people or products. This is not an easy thing to design into a flash. Let alone doing good color plus fast pulse times.

To be sure, you can get flashes that have both action-stopping t.1 times and very consistent color. But those flashes will likely cost you upwards of ten times the price of an Einstein e640. What (Einstein designer) Paul C. Buff did was to split the control circuit in the flash, effectively making it a convertible unit. This was a brilliant move, and one of the main reasons this flash is still an object of lust more than nine years after it first hit the market.

Are you all about stopping action? Say, shooting sports, or freezing water droplets, like the above photo by Jarek Wieczorkiewicz (more on that here.)

Set in Action mode, the Einstein hits a t.1 time of 1/588th of a second at full power, and gets jaw-droppingly faster from there. At 1/256th power, it clocks in at 1/13,500th of a second. So yeah, it'll freeze water in the air.

Shooting catalogue stuff, or portraits? Switch to "Constant Color" mode for a color consistency of just +-50 degrees Kelvin across the power range. Check those numbers against your budget studio flash. Trust me, they're good.

The convertible design of the e640 puts it miles ahead of all but the world's most expensive flashes at a small fraction of the cost. But there are other things to consider, too.

Quality, Reasonably Priced Modifiers

Paul C. Buff sells a wide array of light modifiers for its full line of flashes. They are well-designed, and very moderately priced. This gives you the range to do what you need, and really helps to manage the "all-in" price of a flash system.

Starter example: the small dish- and cone-style reflectors (seen above) are almost laughably cheap, allowing you to inexpensively get the most versatility out of your unit. I have high-output telephoto reflectors (seen above at left) for sports, normal reflectors (middle) for hard light and umbrella reflectors (right) to create beautifully controllable no-spill light from a black-backed umbrella. They are $30, $20 and $13 respectively.

The company's soft boxes and dishes follow this ethic as well. This is what gives that powerful light the versatility to do what you want it to do, without breaking the bank.

Warranty and Factory Support

Here's where many budget flashes drop the ball. Factory support is key to the sustainability of any "big light" system. You'll find this out when you realize you have to send your bargain monobloc back to China for a repair.

The Einstein is factory warrantied for two years. Paul C. Buff doesn't use distributors (they sell direct, which is the main reason they are only fully available in the US.) Because of that, when you call the store, you are also speaking to the factory. They have built a 30+ year reputation for bending over backwards to support their stuff.

Which if course, doesn't really matter. Until one day when it really, really matters.


Speaking of 30+ years, that matters as well. There are lots of studio flash brands out there that did not exist five years ago, and may not exist five years from now.

Big lights are a system you buy — and build — for the long haul. Plan accordingly.

Other Doo-dads

Yes, the Einsteins do things like remote control of power levels (with the appropriate transmitter/receiver combos) and multi-channel/multi-flash operation. But IMHO this is noise on the scale of importance compared to the items listed above.

A big flash can easily last you 20-30 years. Think of it like buying a car. I am more interested in the engine, reliability, safety and ease of repair than I am the cupholders and contrasting leather stitching.

Feature creep (and the related quick obsolescence) can a thing when it comes to big lights. And it is easy to get lost in the minutia of all of the fancy bullet points in the various product listings. This is a long-term purchase. Concentrate on the stuff that really matters.

What About PCB's Other Lights?

They're fine. But if you want an all-in big light, splurge and go for the e640. If you want something small and super portable, maybe look at the DigiBee.

But honestly, it's the convertible design of the Einstein that sets it apart from the competition and makes it worth several times its price. There are a lot of decent flashes out there. But the Einstein is a unicorn.

What About Outside the U.S.?

The only real downside to PCB lights is that they are only readily available in the U.S. Which is a shame for you other folks, really. And the flashes that will be available to you in a given country will vary widely.

But you can use the above as a template for helping you to choose from among the choices offered locally. What I would say is to really dig into the specs — especially color consistency and t.1 times. Then take a hard look at reliability and factory warranty/service. Then ask some local pros. Trust me, if they have bought a studio flash that turned out to be a piece of crap they will most certainly tell you about it. You'll have trouble getting them to shut up.

But hopefully, no matter where you live, this thought template will help you to make a better informed choice no matter which you buy.

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