Tuesday, June 1, 2010
This is the last post for this series, 16 in all. It has been a long and somewhat slow journey, so thanks to all of you who have hung in there reading each post and waiting for this thing to finally come in for a landing.
Do You Need One of These?
So what's the deal with a high voltage battery pack you may ask? Well, it makes the flash recycle really, really fast and adds a lot of reserve capacity. When you need a fast series of shots and are depending on flash for light, it is no longer a luxury, but a necessity. Can all flashes use a high voltage battery pack? No, but those that can will recycle faster and give a lot more flashes than with AA batteries. Some flashes, like the Vivitar 285HV, have a high voltage input that expects around 315 VDC. Quantum Turbo compatible high voltage battery packs have the electronics to make this high voltage from low voltage batteries. Paramount (and others) make a cable to fit between the flash and battery packs that have a Quantum Turbo compatible output jack. You can see mine hooked up in the photo above.
This is the JTL 2409 battery pack, that came with a JTL Mobilight 300 AC/DC studio light. It puts out about 315 VDC for powering the flash tube. It will recharge a 300 WS studio light from a full power dump in around 6 second, but lash it up to a Vivitar 285HV and you get sub 2 second full dump recycling, even faster with other flashes like the Canon 580 EX II. Of course, the studio light is about 4 (or more) times more powerful than most portable flashes, so for equal power settings recycling is on par for either light.
This particular pack uses Ni-MH batteries, so it is light and compact, yet inexpensive. Because of the self-discharge associated with Ni-MH battery chemistry, it is advisable to recharge the pack a day or two before use, but that is a minor issue considering how light it is compared to the SLA (Sealed Lead Acid) based alternatives. It also works with the Canon 580 EX II flash, Sunpak 383 Super, and probably some Nikon flashes too via the appropriate cable.
The JTL High Voltage Battery Pack sells discounted for around $135 making it among the least expensive battery packs available. Click Here to purchase the JTL 2409 battery pack from Amazon. There are other packs available too at various price points, and newer models come out from time to time. Each model has its own advantages and disadvantages, so a little research is advisable.
The cable is a Quantum Turbo compatible made by Paramount. It does the job and cost a lot less than the Quantum cable. So far it has proven reliable after many uses. I couldn't find it on Amazon, but here is a link to it on B&H (another great place for photo gear). http://www.bhphotovideo.com/bnh/controller/home?O=WishList.jsp&A=details&Q=&sku=40186&is=REG
Here are some more photos, not that you need them, but since I got a bit carried away photographing this thing I might as well make them available.
The naked battery pack. Notice the ventilation holes in the side. If the circuit overheats, then bad things can happen. To get around this one can either limit the number of pops or supply adequate ventilation (or both). Bear in mind that these packs are made for a 300 WS studio flash, so when lashed to a portable flash with around 50 WS, they are hardly working to recycle a full power dump. For the record, a WS is a Watt-Second and represents an amount of energy equal to that many Watts for one full second.
The flip side has ventilation too.
Even the bottom is ventilated.
All that ventilation gets duplicated in the case too.
That's all Folks
I swore I would never do another long series and then proceeded to hammer out the longest yet over these past few months. So much for promises. From now on, the only thing I promise is not to promise anything and just let the blog grow however it must. Anyway, last post, hope you found something useful in this drawn out series.
I'm thinking of posting a more technical article on color shift over min/max output range for my studio lights. Also thinking about a lighting setup using a gridded light to increase contrast. Another thought is to show a basic one light setup. In other words, I haven't yet figured out what to do next, so come on back to find out
Posted by Gene Lee at 10:12 AM