Quantum, the well known American company, have been around for a long time and have always had a good reputation for making high quality powerful flashguns and battery systems.
The Turbo Compact battery and Quantum T5d I looked at make a great combination if you are thinking of buying a portable flash system that can be used inside the studio or on location.
The Quantum Turbo Compact battery is small as the name suggests, only 14x4.5x4.5cm in size. It comes with a charger and connecting lead to the Qflash and only weighs 16oz. It has two output sockets, one for flash and one to power cameras via a dedicated lead.
On the side of the battery there is an on/off button, a 'fuel gauge' for the power, 4 lights that show ¼, ½, ¾ & full power and two more indicators, one for camera and one for flash.
Using it with the T5d the Turbo Compact will give 225 shots at full power with a 3 second recycle time. If you use the battery to power both Q flash and camera you get 150 and 250 shots respectively.
For ease of use the battery can be mounted onto a tripod, with the camera mounted to the top of the battery, very neat.
The Quantum T5d is pretty small, just 15x7.5x7.5 cm and only weighs 26oz. It comes with camera sync lead, a 12cm reflector and diffuser, a plug in flash / modelling lamp, plus an ear piece connector and retaining screw for a camera bracket. With a power of 150W/s portable flashgun which can work in several different modes, Manual, Auto, Auto fill, TTL and Strobe.
In Auto the T5d power can adjust in 1/3 steps over a wide range, from f1.4 to f22 at 100 ISO in 25 settings. In Manual, it has 19 power settings from full to 1/64 th again in 1/3 steps. It's simple to use with just a few buttons for Test, Mode, Set and Option, making changes is pretty straightforward once you get used to them. What will take a little time, is working out which mode or option you want to use!
Luckily the instruction book is very easy to read and well laid out with plenty of diagrams. Because the T5d can be used in so many ways, the simple instructions guide you through each mode in an easy step by step way. As you work through it, you realise just how good the specifications are, a few I liked are being able to save 8 program settings, the flash sensor limit, helping to ensure you don't overexpose on long distance shots and being able to use the modelling lamp, on for only a few seconds at a time, but a real benefit.
I was very impressed with the T5d's TTL system as it can be dedicated to all the major camera brands via a dedicated lead and will display and track the cameras f number and film speed, allow for rear curtain sync and provide infra red auto focus assist. Even if your camera doesn't support fill/flash ratio, the QTTL ratio setting tracks the camera f stop as it changes, providing automatic fill/flash ratio, a nice feature.
Quantum has always realised the need to provide a full range of accessories to offer a complete system and the Qflash has some really good ones. All use the turn and lock system to attach to the gun. Apart from the standard reflector, there is a 22cm Tele Portrait reflector, a W/Angle diffuser, a 30cm Sq. Soft Box, a Snoot and a Bare Bulb enhancer to name a few. So when you buy the gun you always know that you can add on the accessories later when you need them. Apart from the lighting accessories Quantum also make versatile brackets for camera and pole mounting and many other useful gadgets including the Radio Slave 4i, for wireless sync control.
If you are thinking about buying a portable flash system that will give you power, a TTL system, good recycle times, and a wide range of accessories, the Quantum T5d is well worth looking at. To give you an idea of price, around £338 for the Turbo Compact battery with charger, about £590 for the Quantum QT5d plus around £100 for the TTL lead depending on your camera model.