PowerTracking

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ControlTL allows you to adjust your remote studio flash’s output power directly from the camera position in three ways:


Basic Power Control: With just a ControlTL transmitter on your camera, use your camera’s FEC to adjust remote flash output power. This is called PowerTracking - Full Manual and is the default when you are not using an AC3 ZoneController on your ControlTL transmitter. See the Basic Power Control section for more information.

Automatic PowerTracking: When engaged, any changes to aperture and ISO on your camera are automatically tracked by your remote flash output power to maintain the current exposure level. For example, if you open the aperture on your camera by one stop, then the power output level on your remote flash will decrease by one stop.


There are two ways to engage Automatic PowerTracking:

  • No AC3 ZoneController on your ControlTL transmitter - Set the PowerTracking mode in the PocketWizard Utility to a setting other than Full Manual for Automatic PowerTracking using just your camera’s controls.
  • AC3 ZoneController Auto Mode - Add an AC3 ZoneController set to A (Auto) on your ControlTL transmitter to adjust power output level independently for up to 3 zones of light in conjunction with Automatic PowerTracking.


AC3 ZoneController Manual Mode - With an AC3 ZoneController on your ControlTL transmitter, you can have simple and direct control over your flash output power. See the section on Using an AC3 ZoneController for more information.


Basic Power Control

With only a MiniTT1 or FlexTT5 on your camera, your camera’s FEC (Flash Exposure Compensation) control will adjust your flash power output level for all supported flashes connected to ControlTL receivers.

Nikon: The camera’s FEC or EC (Exposure Compensation) control will adjust flash power output level. The Nikon D3 series cameras do not have an FEC adjustment. You can use the EC adjustment on all Nikon cameras, including the D3 series, whenever a flash power output level adjustment is needed.

Canon: Both the camera’s ISO and FEC controls will adjust flash power output level. Changes to FEC will adjust flash power output level as shown in the table on the right. Changes from the ISO used for your first picture will adjust flash output power level relative to FEC. For example, if your first picture was at ISO 200, and you adjusted ISO down to 100, your flash power level would be 1 stop brighter for all FEC settings.

This operation assumes PowerTracking is set to Full Manual in the PocketWizard Utility, which is the default.


You can use any PocketWizard receiving radios together in the same exposure, including other ControlTL radios. Remember that studio and manual flash output will not be calculated as part of an E-TTL / i-TTL exposure.

ControlTL® Center Point The center point for all ControlTL operations, including Basic Power Control, PowerTracking, or when using an AC3 ZoneController, is 3 stops down from your flash’s maximum. For example, in Basic Power Control this means 0 on your camera’s FEC equals 1/8 on your flash and FEC +3 equals 1/1 (full power). This setting may be customized using the PocketWizard Utility under the PowerTracking tab.

Camera FEC Range and Basic Power Control: You can change the center point to better match your camera’s FEC range by adjusting the Flash Exposure Compensation control in the PocketWizard Utility for each PowerMC2. This setting must be configured on each receiving PowerMC2 radio.


Automatic PowerTracking

When Automatic PowerTracking is engaged, any changes to aperture and ISO on your camera are automatically tracked by your remote flash output power to maintain the current exposure level. For example, if you open the aperture on your camera by one stop, then the power output level on your remote flash will decrease by one stop.

To engage Automatic PowerTracking when you are not using an AC3 ZoneController, set the PowerTracking mode to a setting other than Full Manual. This is done in the PocketWizard Utility for your transmitting ControlTL radio only. PowerTracking has several modes of operation available. See the PocketWizard Utility section on adjusting this setting via the PowerTracking Tab for more information.

The following directions are for the PowerTracking mode Center on ISO & Aperture with First Shot.

In this mode, the aperture and ISO as set on the camera for the first exposure will be aligned with the ControlTL center point (3 stops down from your flash’s maximum output power). For example if your camera is set to ISO 100 and F:5.6 for its first exposure, then those exposure settings will yield a flash output power of 1/8. See the ControlTL Center Point section for more information.


To set the aperture and ISO values that will be aligned with the ControlTL center point:

  • Turn on your camera and transmitting MiniTT1 or FlexTT5, but wait to press your shutter button or take any pictures.
  • Set the aperture and ISO you wish to align with the center point. Set the shutter speed as desired, however changes to shutter speed will not affect PowerTracking.
  • Press the shutter button to take a picture. The center point is now aligned with your aperture and ISO settings.
  • Use your camera’s FEC control to get the exposure the way you want it. If you are unable to achieve the exposure you want using this control, try adjusting the Flash Exposure Compensation control in the PocketWizard Utility for each PowerMC2, use a different aperture or ISO, or consider an AC3 ZoneController.
  • As you adjust your camera’s ISO and aperture, flash power output will automatically track to maintain the current exposure level.


To change the values used for the center point, turn off your transmitter then turn it back on and follow these steps again. See the PowerTracking Tab in the PocketWizard Utility section below for more information.

IMPORTANT NOTE: Shooting in Shutter Priority/Tv, Program, Full Auto, or shooting quickly or making rapid exposure changes is not recommended. The flash values may change rapidly and your remote flash may not be able to keep up. Honor your flash’s ready wait time or “dump” as necessary.


Flash Exposure Compensation (FEC) can be set in many places and all values are added together.

FEC can be set:

  • On the Power Dials of the AC3 ZoneController
  • On the camera for all zones except AC3 Manual zones
  • For transmitting radios, the PocketWizard Utility can adjust the PowerTracking center point for ISO and aperture which affects all zones
  • For a PowerMC2, PowerST4, or AC9 AlienBees Adapter connected to a FlexTT5, the PocketWizard Utility can adjust FEC for the directly connected flash on the PowerTracking tab

If the combined FEC settings are more or less than your flash’s capabilities, then the flash will operate at maximum or minimum output accordingly.


Using an AC3 ZoneController

An AC3 ZoneController on your transmitting ControlTL radio allows you to adjust the remote flash output power for up to 3 zones independently, in either Manual or Automatic modes.

Set the Zone on your receiving ControlTL radio to Zone A, B, or C as desired.


Manual Mode: With an AC3 Zone Switch set to M (Manual), the AC3 Power Dial for that zone sets the absolute flash power output as shown in the table for Basic Power Control. Your camera’s FEC/EC, ISO, and aperture controls will not affect the flash output power levels for AC3 zones set to M.

Automatic Mode: With an AC3 Zone Switch set to A (Automatic), Automatic PowerTracking using Center on ISO & Aperture with First Shot is engaged. See the Automatic PowerTracking section for more information. The AC3 Power Dial for a zone sets the flash power output level for that zone relative to the ControlTL center point. Your camera’s FEC control can be used to adjust flash output power level for all zones set to A (Auto).

Off: With an AC3 Zone Switch set to Ø (Off), flashes in that zone will not trigger.