Feed Your Flash Ni-MH's
Our battery drawer at The Sun was full of industrial Duracells. The supply never seemed to go away.
Oh, we used them by the case. It was only that Jeff, our Gear Guru, made sure the battery box was pretty much bottomless. Did some of the batteries find their way into R/C cars, or maybe baby monitors? Maybe -- I'm not sayin'.
But when we started going through them too quickly Jeff would occasionally remind us that we did not, in fact, have to replace the batteries in our flashes every day. We got the message.
It is against that backdrop that I'll tell you that I stopped using the "free-for-me" alkaline batteries about a year ago. It was after reading some of the reader responses to this post, where we talked about some of my preferences exterior power options for speedlights. I got an earful in the comments and in emails.
What started out as a little battery experiment has led to a wholesale change of approach when it comes to how I power my flashes.
Nickel-Metal Hydride (Ni-MH) rechargeable batteries and your flashes are a match made in heaven. I have long-since abandoned the company-supplied alkalines to switch to the more expensive batteries, which I had to buy out of my own pocket.
Why? They are so much better than alkalines, it is a no-brainer. In fact, they are better for your flashes in just about every way.
(More after the jump)
Technically, my Duracells, were free -- for me. But for the sake of argument, let's assume that alkalines cost you 50 cents each and Ni-MH's cost $2.00 each. (Which is pretty close to being correct as of today.)
Ni-MH's can be recycled hundreds of time if you care for them correctly. Which takes the cost down to less than couple cents per cell over time. Sure, it costs some money for the power to charge them. But that is negligible compared to the cost of replacing an alkaline battery.
Ni-MH's: More Convenient
But there are more to cost than just purchase and recharging costs. Time is a cost, too. And if you don't get by the office very often (a practice I employed for a variety of reasons) you can find yourself having to schedule a "supply run." That bites.
Ni-MH's can be bought in packs that include 4 AA's and a 1-hour charger that can be plugged into the wall (easy enough) or plugged into your 12v cigarette lighter jack in your car. Which means you can top off between assignments any time you like, even when shooting on location or in your car heading to the next shoot.
That is about as convenient as it gets. And any choice that keeps me out of an unnecessary trip to the office is a good thing.
I even ran a 12v line (only powered when the car was running) back to the trunk for easy swaps when I was putting gear back into the car. So in terms of both money and timed saved, NiMH's kick butt.
Ni-MH's: Faster Recycle Time
None of this would matter if the batteries were crap. Fortunately, that's not the case.
At 1.25 volts for each Ni-MH battery (compared to 1.5 for alkalines) you'd think that NiMH's would be sucking wind when it came time to recycle your flashes. After all, 4 NiMH's (connected together in series) only have 5 volts, compared to 6 volts for alkalines.
To be sure, Ni-MH's are at a disadvantage in the voltage department. But voltage is not the only thing that matters in recycling a flash. When that flash is chirping away and you are waiting for the little light to turn red, what a flash needs is current. And NiMH's deliver current in spades.
Think of two hoses, with the first having a little more water pressure than the second. But the first one is a garden hose, and the second is a fire hose. The fire hose may have slightly less water pressure, but it can still deliver more water per second. Ditto the Ni-MH battery with current.
Example: My SB-26's take 6-7 seconds to recycle a full-power, manual shot with good alkalines. But with fresh Ni-MH's, they recycle in 3.5-4 seconds.
That lower-voltage/faster-recycle thing is counterintuitive, but true. And to be honest with you, if they were slower than alkalines I would still be mainlining the Duracells.
Finally, Ni-MH's are greener than alkalines, if that kind of thing matters to you. An old friend of mine (who I just found out happens to read this site from Cairo) once told me that environmentalists make pain-in-the-butt neighbors, but great ancestors.
The green thing is not the end-all for me. (I am getting greener -- I now proudly recycle 100% of my bad jokes.) But as icing on the cake, it's pretty cool.
For instance, if your spouse is a serious treehugger, you may completely forget to mention that Ni-MH's are faster, cheaper and more convenient for you. Instead, you might offer that you did this just for her, as a gesture to her environmental sensitivities. After all, what maters to you matters to me...
(Now, can I please watch the Florida football game next Saturday instead of mowing the lawn? Thanks, honey. You're the greatest.)
Ni-MH's: Selection, Care and Feeding
Driving Ni-MH's are a little different than alkalines. So there are a few things you'll want to know.
First, "mAH" matters. mAH stands for miliamp-hours, and it tells you how much power the little guys can hold. All things being equal, go for the higher number. In fact, I would say get at least 2500 mAH batteries. Unless you see 2750's, in which case buy them. They are so cheap over the long haul that you may as well buy yourself more capacity.
Second, resist the temptation to get the 15-minute chargers. They work, but are very hard on the batts. Best for them is the overnight trickle chargers, but that could cramp your style. (I like to rotate shooting an charging sets on location.) The 1-hour, or 1.5-hour chargers are a very good compromise.
Third, think about your batteries as being a quartet. They like to sing together. Batteries that are charged and discharged together over time perform better and last longer. I like to label my sets with a number or letter. (My first idea, to label them as sets with a woman's name, was completely misunderstood and I am not going to talk about that further except to say not to do it if you are married.)
I have two sets of batteries (and one, four-cell charger) for each flash. This works just great, as I can charge the "B" sets on location faster than I can shoot down the "A" sets. Essentially, you have unlimited power.
There is one blemish on the record of Ni-MH's. They self-dischage faster than alkalines. Which means two things to consider. First, I tend to top them off (no memory - top them off any time) within a couple days of when I am going to need them. Basically, I am just always shooting and rotating them through chargers, which they really seem to like.
It is for that reason that I still use Ni-MH's in my Pocket Wizards, which are so stingy on power that I have to try to remember when the last time I changed the batteries was.
Some people swear by the new Ni-MH "Eneloop" batteries (by Sanyo) which reportedly self-discharge more slowly. I have not tried them yet but plan to. If you use them, please report on them in the comments.
Where to Get Them
There are several websites that specialize in rechargeables. Amazon sells them, too. But to be honest, I have been very happy with my sets from local discount stores. Wal-Mart, specifically. (I know. Sorry.)
For $18, I get a set of 2700 mAH's and a 1.5-hour charger that works on US A/C, car battery or in A/C in Europe. I get the "B" set of batteries for each flash (no charger needed) for another $8.00. This is an instance of when you would want to buy local -- or at least in your country. It does you no good to get a set and a charger with a US and Euro plug if you are in the UK.
Wherever you get them, do yourself a favor and switch to Ni-MH's if you haven't already. There's a lot to like about them.