Crafting an image with Pocket Wizard’s AC3 Controller
In this tutorial we are going to see how, step-by-step, we can build an image using the AC3 controller. Using the different channels we will be able to setup and enable each light independently, fine tune the light output in e-TTL or manual mode as needed. We will repeat this process until we have completed out setup and then put it all together.
Pocket Wizard’s E-TTL compatible system, called ControlTL, consists of the MiniTT1 and FlexTT5 units. The MiniTT1 is a lightweight transmitter that takes the E-TTL signal from the camera hotshoe and transforms it in radio signals that are sent to the receivers. The FlexTT5 is the receiving side of the radio signal. The FlexTT5 features a hotshoe to attach a speedlite and can act as both a transmitter or a receiver (called a “trasceiver”).In fact, the TT5 is a better sender than the MiniTT1 as it provides a better triggering range.
For the best user experience, the The Pocket Wizard TTL system offers a 3rd unit, the AC3 controller, which connects to the hotshoe of the commander unit and enables “Zone Control”, the independent power and mode setting of up to 3 groups of flashes (A-B-C).
For each group, the AC3 provides a switch that can set the group to E-TTL or Manual mode or turn it off completely. A responsive analog wheel lets the user set the dial in the desired power setting for the corresponding group. The power of a group firing in E-TTL mode can be controlled using flash exposure compensation of -3 to 3 stops in 1/3stop increments. The exposure compensation is calculated based on the theoretical “correct” exposure provided by the E-TTL algorithm in the camera. When a group is set to manual mode, the -3 to 3 stop scale is translate to absolute power values on the flash unit.
Let’s first go through the ingredients for this shoot:
- Lastolite Hotrod Octa 70 + 600EX-RT + TT5 as main
- Lastolite Hotrod Stripbox 120 + 430EX + TT5 as fill
- A bare 580EX + TT5 in a little hole in the background, used to backlight the smoke
- Evelyne and her lovely blue eyes
- and the magic brushes of our MUA, Monera
Before placing all flashes in the setup, it’s a good practice to test that they are all connected and syncing correctly. A easy way to do that is just to take a picture of them, with all channels active.
Step 1: Setting the main light
When working with multiple flashes, the best way to build up an image is to start with a single light and gradually add secondary illumination, one flash at the time.
The AC3 controller enables this workflow by providing and off mode for each channel independently. With a flip of your fingertip, you can switch each light on and tune its power to the desired effect.
Here, we are testing the main unit in E-TTL mode, which we will be using with +0.3 exposure compensation. It’s a good practice to use the channels A-B-C also in hierarchical order for the lights. A: Main, B: Fill, C: Background or an accent. This is not mandatory, but helps to easily identify a light source by its group.
Step 2: Setting the fill
After we have tuned the main light to the desired level, we switch it off on the AC3 controller and we turn the group B on. We have 1 flash in group B. This flash has a warm-up gel and is fitted into a strip box (a long softbox) located at ground level.
Using the power dial, we set -1.6 exposure compensation in E-TTL mode. Having the main light and this fill in E-TTL, makes the power adjustments relative to each other, enabling to effectively create a balance between them. This looks like a scene from a horror movie as we are only seeing the light coming from below. I takes some practice to recognize how each light should look like independently. It’s not nice alone, just a piece of the puzzle. Hold on a sec while we fix the background to put it all together.
This 3rd image shows the background light. In this case, we popped a speedlite through a small hole we left in the back of the background. This 3rd speedlite has a full-blue gel on and we added some canned smoke for the effect.
Given the random nature of the spreading smoke, we set this speedlite to manual power to 1/16 (-1 power setting on the AC3) to avoid eTTL getting crazy with the flowing smoke and have a consistent background exposure in every frame.
You may also be wondering about the little beam of light shinning on our model. It’s a small LED video light that I often use to help me focus in low light conditions.
All pieces together
Finally, we switch all the groups on and we can proceed to photograph the carefully built scene. We explore many different poses and Evelyne shows her professionalism, working with me through different alternatives, looking for that ‘aha!’ moment when you know you’ve got it.
In the process, I also explored different permutations of the lights. Main and Fill? click. Main and background? click,click. Adjust background power? trrrr (wheel turning … it is all done without breaking the flow of the shoot, using the AC3 controller on camera, at the tip of your fingers. In this shoot, I particularly thank the full remote control of the background light, which was literally squeezed in a small hole between the plexi background and the supporting table. Getting there was a work of contorsionism so I was very glad to had to bend my back only once to put it there and not every time that a notch of a stop needed to be adjusted… trrrr (wheel turning again)
The one interruption mid-flight was removing the warm-up filter from the fill light. It was giving me a too strong cast for my taste and I decided to part with it. I just remove it from the speedlite and continue shooting. We are removing an obstacle in the light path. E-TTL automatically compensates for the extra light, giving me back my original ratio between main and fill. No additional tuning process was required.
Although Evelyne makes it very hard to have a bad frame, after hours of careful selection, one image stood above all others. All the pieces of the puzzle finally came together.