Many Speedliters are fond of using the ST-E2 Wireless Transmitter in lieu of a master Speedlite. I am not among them. In fact, I discourage people from getting the ST-E2.
The thinking in favor of the ST-E2 is that it is about half the price of a 580-series Speedlite. I concur: about half the price and less than half the functionality.
My experience has shown that the range of the ST-E2 is shorter than a 580EX, both indoors and out. This is due to the fact that the flashtube on a 580EX is much stronger than the small tube inside the ST-E2. Further, the range of the ST-E2 flashtube is impeded by the thick red plastic panel that is there to block the visible portion of the flash. (If it was not blocked, it would add uncontrolled, on-camera flash to the exposure.)
In terms of flexibility, the ST-E2 literally has none. Unlike a 580EX, which can pan 360º, the ST-E2 will only control Speedlites that are within an 80º angle in front of the lens. In contrast, by panning the head on a 580EX, I can hit a slave that is to the side or behind me. The flexibility of the 580EX is a huge advantage when it comes to creative Speedliting.
A third limitation of the ST-E2 is that it can only control groups A and B. Given the extra steps needed to run Group C, this is not a huge downside. On the positive side, the ST-E2 provides the A:B ratio control quite easily via a sliding lever. So, for novice Speedliters, this trade-off is fine.
A fourth limitation, and one that looms larger as I become more accustomed to controlling my Speedlites via the LCD screen on my camera, is that the ST-E2 (like the original 580EX) cannot be controlled by the camera LCD. When you are starting out, this shortcoming will not seem like an issue. As you become an advanced Speedliter, you will learn to appreciate the convenience of controlling your Speedlites via the camera LCD.
Gear recommendation #1: If economy is a concern, start with a 430EX and an extra-long E-TTL cord. Many people think that they need to spend $250 on an ST-E2 to get their one Speedlite off-camera. I say spend $65 on an E-TTL cord instead. Not only will you save a big chunk of dough, you’ll be able to control the Speedlite via the camera LCD (assuming you have an EX II Speedlite and a compatible, late-2007 or newer camera.
Gear recommendation #2: While you are learning to master your first Speedlite, start saving for a 580EX II. Then, when you want to start shooting with multiple lights, you can buy a 580EX II and use it as an off-camera master (thanks to the extra-long E-TTL cord you bought earlier). Now you have a 580/430 combo for about the same price as two 430s and an ST-E2. I’ve no doubt that you’ll find the versatility and power of the 580EX II + 430EX II + extra-long E-TTL cord to be far greater than a pair of off-camera 430s that have to remain in front of the lens
So what if you already have an ST-E2? When you eventually outgrow it, there is always eBay.
Portions of this article excerpted from my ‘Speedliter’s Handbook‘
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