March 2013

Speedlite 430EX II / Speedlite 600EX-RT

Photo 1: 430EX II

Photo 1: 430EX II

Speedlite 430EX II Guide number 43
Flash coverage:
14 mm, 24 - 105 mm
Silent recycling, quick recycling
Wireless slave function

Photo 2: 600EX-RT

Photo 2: 600EX-RT

Speedlite 600EX-RT Guide number 60
Flash coverage:
14 mm, 20 - 200 mm
Complete feature set to satisfy the demands of professionals
Silent recycling, quick flash
Radio and optical wireless functions

This month's technical report brings you technical information on the Speedlite 430EX II (Photo 1) and the Speedlite 600EX-RT (Photo 2) flash units.

Speedlite 430EX II

The Speedlite 430EX II is a mid-range Speedlite for true flash photography. It is equipped with the following functions.

(1) E-TTL / E-TTL II autoflash

The 430EX II supports the E-TTL / E-TTL II autoflash system (Figure 1), which was developed to meet the demands of the digital camera era. This system fires a weak pre-flash just before the main flash, measures the flash intensity necessary to properly illuminate the subject, and then fires the main flash (this sequence takes place in an instant). The E-TTL II autoflash system provides even more precise and stable flashes by utilizing the lens-to-subject distance. The system's algorithm is actually contained in the camera, so the system can be improved with each new model development.

Figure 1: E-TTL II autoflash program profiles

Figure 1: E-TTL II autoflash program profiles

(2) Powerful flash with wide flash coverage
Figure 2: Built-in wide panel

Figure 2: Built-in wide panel

The 430EX II's flash-coverage angle can be set either automatically or manually to match lens focal lengths (i.e., the photographic angle of view) spanning 24 to 105mm (35mm-film equivalent focal lengths). The guide number, which indicates the flash intensity, varies between 11 and 43 (ISO 100, in meters) depending on the flash-coverage angle. The flash unit also has an auto zoom for sensor size function that automatically sets the flash-coverage angle according to the imaging element's size (full-frame, APS-H, or APS-C).

When the built-in wide panel (Figure 2) is used, the flash coverage is set to match a 14-mm wide-angle lens.

(3) Silent recycling

The recycling whine that occurs when building up the high voltage needed to fire the flash has been virtually eliminated with technology that controls the microprocessor frequency.

(4) Quick recycling

The 430EX II can quickly recharge its main capacitor from fully discharged to fully charged in approximately three seconds. Depending on the amount of charge left in the main capacitor, the recycling time varies between approximately 0.1 seconds and three seconds.

(5) Enhanced flash functions

The 430EX II comes with many flash functions: exposure compensation, FE lock, high-speed sync, 2nd-curtain sync, and manual flash (settable in increments of 1/3 stops).

Figure 3: 430EX II bounce adjustment range

Figure 3: 430EX II bounce
adjustment range

Figure 4: Mounting foot lock mechanism

Figure 4: Mounting foot lock mechanism

(6) Bounce adjustment

Bouncing (reflecting) the flash off the ceiling or walls creates soft, natural-looking illumination. The 430EX II's flash head can be tilted upwards and swiveled horizontally, permitting a wide range of bounce flash techniques (Figure 3).

(7) Wireless slave function

When the 430EX II is used with a master-function-equipped Speedlite or an EOS 7D, 60D, or Kiss X5 *1 / X6i *2 camera, the 430EX II can be placed away from the camera and fired wirelessly. Setting up multiple flash units to act as slaves allows for more sophisticated lighting arrangements.

*1. Japan: EOS Kiss X5, Americas: EOS Rebel T3i, Europe/Asia/Oceania: EOS 600D
*2. Japan: EOS Kiss X6i, Americas: EOS Rebel T4i, Europe/Asia/Oceania: EOS 650D

(8) Quick attachment and improved reliability

The mounting foot lock lever makes it easy and foolproof to attach the flash unit to the camera. The locking mechanism has a lock release button to prevent the lock from releasing accidentally (Figure 4).

The mounting foot is made of metal for more strength. Also, a protective cover goes over the foot when attached to a camera to improve the water and dust resistance around the flash contacts.

Speedlite 600EX-RT

The Speedlite 600EX-RT is a high-end Speedlite with the advanced performance and reliability professionals demand. It is equipped with the following functions.

(1) E-TTL / E-TTL II autoflash and external flash metering

In addition to having the same E-TTL / E-TTL II autoflash system as found on the 430EX II, the 600EX-RT has an external flash metering function for users familiar with the characteristics of external flash metering units.

(2) Even more powerful flash with wider flash coverage

Figure 5: Light distribution setting

Figure 5: Light distribution setting

Figure 6: 600EX-RT bounce adjustment range

Figure 6: 600EX-RT bounce
adjustment range

Figure 7: Catch light panel

Figure 7: Catch light panel

Photo 3: Color filter

Photo 3: Color filter

Powerful flash with wide flash coverage

The 600EX-RT's flash-coverage angle can be set either automatically or manually to match lens focal lengths (i.e., the photographic angle of view) spanning 20 to 200mm (35mm-film equivalent focal lengths). The guide number, which indicates the flash intensity, varies between 26 and 60 (ISO 100, in meters) depending on the flash-coverage angle. When the built-in wide panel is used, the flash coverage is set to match a 14-mm wide-angle lens.

Fine light distribution settings

Users can select the light distribution characteristics from Standard, Guide number priority, and Even coverage (Figure 5). The Guide number priority setting narrows the flash-coverage angle more than the Standard setting to increase the guide number. The Even coverage setting expands the flash-coverage angle more than the Standard setting to minimize vignetting at the edges of the frame. This function relies on a microstep drive that precisely controls the flash head zoom position.

The flash unit also has an auto zoom for sensor size function that automatically sets the flash-coverage angle according to the imaging element's size (full-frame, APS-H, or APS-C).

(3) Silent recycling

The recycling whine that occurs when building up the high voltage needed to fire the flash has been virtually eliminated with technology that controls the microprocessor frequency.

(4) Quick flash function

The 600EX-RT has a quick flash function that can fire the flash before the main capacitor is fully charged. In this mode, although the time to reach full charge is approximately 5.5 seconds, the unit is ready to flash in approximately 3.3 seconds from a fully discharged state. In the normal mode, the recycling time varies between approximately 0.1 seconds and 5.5 seconds depending on the amount of charge left in the main capacitor.

(5) Bounce adjustment

The 600EX-RT provides a larger bounce adjustment range than the 430EX II (Figure 6). It also has a built-in catch light panel to create catch lights in subjects' eyes when bouncing the flash (Figure 7). It is also possible to angle the flash down for close-up photography.

(6) Color filter for white balance adjustments

During flash shooting, the white balance is adjusted based on the color temperature of the flash. However, even if the white balance is correct for the main subject, unnatural photos can still result when the color temperatures of the flash and the ambient lighting are different. This can happen when the flash does not reach the background that is tinted by the ambient light's color temperature. This phenomenon can be alleviated by placing a color filter in front of the flash head to match the flash's color temperature to that of the ambient lighting (Photo 3).

(7) Radio wireless function

The radio wireless function lets you place the 600EX-RT as a slave flash unit anywhere within a radius of approximately 30 meters of the master flash unit. Since the radio wireless function is less susceptible to the optical wireless function's directional limitations and to blockage by obstacles, it gives more lighting (slave positioning) flexibility both in front and behind the master slave unit.

Bidirectional radio communications can also be used for remote release and linked shooting functions. To shoot with these radio wireless functions, multiple 600EX-RT units or a 600EX-RT unit and a ST-E3-RT Speedlite transmitter are needed.

There are some limitations on the radio wireless function when using the 600EX-RT with a camera released before the 600EX-RT. Additionally, the radio wireless function can only be used in countries and regions where its use is permitted.

Radio wireless shooting with multiple flash units

The radio wireless function can be combined with a master flash unit to control up to 15 slave units divided into five groups (Figure 8). Because the slave unit settings and charge status can be confirmed from the master unit, lighting adjustments after the slaves are positioned can be done more efficiently.

Remote release

A release signal can be sent from a slave flash unit to trigger the release on the camera via the master flash unit. Test flashes and modeling flashes are also possible. The SR-N3 remote release cable is necessary is some situations.

Linked shooting

Linked shooting is a function that automatically triggers the release on slave cameras when the release is triggered on the master camera (Figure 9). This allows the user to aim as many as 16 cameras at a subject and shoot the subject from multiple angles simultaneously.

Figure 8: Radio wireless shooting

Figure 8: Radio wireless shooting

Figure 9: Linked shooting

Figure 9: Linked shooting

Figure 10: LCD panel

Figure 10: LCD panel

Figure 11: Dust Wipe mechanism

Figure 11: Dust Wipe mechanism

Figure 12: Dust and water protection

Figure 12: Dust and
water protection

(8) Optical wireless function

The 600EX-RT comes with optical wireless master and slave functions that are compatible with the 580EX II and other flash units.

(9) Dot-matrix LCD panel

The 104 x 172-dot LCD panel (Figure 10) provides detailed information about the 600EX-RT in a very legible format. The background color changes according the settings to give the unit's status at a glance.

(10) AF assist beam compatible with 61-point area AF systems

The 600EX-RT's AF assist beam is compatible with the 61-point area AF systems on the EOS-1D X and the EOS 5D Mark III.

(11) Customization

The 600EX-RT has 18 Custom functions and seven Personal functions for full customization of the flash unit.

(12) Excellent reliability
Contact reliability

The 600EX-RT has a Dust Wipe mechanism (Figure 11) that slides back and forth across the flash contacts as the mounting foot lock lever is moved. This mechanism clears away any dust or contamination that has built up on the accessory shoe to improve the reliability of flash-camera communications. The lock lever's movement also pushes a mechanism that varies the contact pressure to ensure that the flash contacts make a firm connection.

Dust and water resistance

The 600EX-RT is protected by the same excellent dust and water resistance as the EOS-1D X. External covers are sealed with C-rings, the battery compartment cover and other openings are protected with packing and rubber materials, and a dust-resistant/water-resistant adaptor attaches to the mounting foot (Figure 12).

(13) System accessories

The accessories shown in Figure 13 are available to suit professional flash applications.

Figure 13: System accessories

Figure 13: System accessories

Digital Cameras and Flash Units

Guide number and ISO speeds

The guide number (GNo.) of a flash varies according to the ISO speed. For example, a flash with a GNo. of 10 at ISO 100 will have a GNo. of 14.1 at ISO 200 and 20 at ISO 400. In other words, increasing the ISO speed two stops doubles the GNo.

With film cameras, flash photography could only use the ISO speed of the loaded film. With digital cameras however, it is possible to change the ISO speed and use high ISO speeds when the subject is distant.

Raising the ISO speed too much results in increased noise. Therefore, using a powerful flash lets you shoot at a lower ISO speed for better picture quality with less noise.

Guide number and aperture value

The shooting distance with a manual flash can be calculated roughly by dividing the GNo. by the aperture value (when in complete darkness). For example, with a GNo. of 10 and an aperture of f/2, the shooting distance is about five meters. Moving closer than five meters will overexpose the subject and moving farther away will underexpose the subject.

The E-TTL / E-TTL II autoflash system automatically adjusts the flash intensity without needing this kind of calculation. Nevertheless, even when using autoflash, it is useful to remember that "GNo. divided by the aperture value" gives the flash shooting distance to get a rough idea of the effective flash distance.

Lighting effects possible with an external flash unit

Where a built-in flash can only light the subject face on, an external flash unit lets you light the subject from many different angles with bounce flash, wireless shooting, and other techniques. Wireless shooting with multiple flash units can produce complex light and shadow effects, and bounce shooting can create a soft atmosphere with indirect lighting.

Because you can check your shots immediately with a digital camera, you can have fun experimenting with an external flash to come up with different lighting effects.

Parameter 430EX II 430EX
Guide number (ISO 100, in meters) 25 - 43 (15 when using the wide panel)
Flash coverage
(as a focal length with a 35mm full-frame sensor)
Approx. 24 - 105 mm (14 mm when using the wide panel)
Auto zoom adjustment for the sensor size Yes
Flash modes Normal flash E-TTL II / E-TTL / TTL autoflash
High-speed sync Yes
Manual flash 1/1 - 1/64
(1/3-stop increments)
1/1 - 1/64
(1-stop increments)
Firing features FE lock Yes
Exposure compensation ±3 stops (1/3-stop increments)
First-curtain /
second-curtain sync
Yes
Modeling flash Yes
Color temperature information transmission Yes
Wireless slave feature Yes
Bounce adjustment range 90° up, 90° right, 180° left
Recycling Min. recycling time Approx. 3.0 seconds Approx. 3.7 seconds
Silent recycling Yes No
Unit control from camera Yes No
Custom functions 9 6
AF assist beam (1 - 9 AF points) Yes
Power source Four AA alkaline batteries
(Also accepts Ni-MN and lithium batteries)
Mounting foot Attachment method Quick-lock/release lever Screw collar
Material Metal Engineered plastic
Bracket compatible Yes
Dimensions (w x h x d) [mm] 72 x 122 x 101
Weight (unit only, no batteries)
[approx., grams]
320

Table 1: Main specifications of the 430EX II and the 430EX

Parameter 600EX-RT 580EX II
Guide number (ISO 100, in meters) Approx. 26 - 60
(15 when using the wide panel)
Approx. 28 - 58
(15 when using the wide panel)
Flash coverage
(as a focal length with a 35mm full-frame sensor)
20 - 200 mm
(14 mm when using the wide panel)
24 - 105 mm
(14 mm when using the wide panel)
Light distribution setting Standard / Guide number priority / Even coverage No
Bounce adjustment range 90° up, 7° down, 180° left and right
Exposure control E-TTL II / E-TTL /
TTL autoflash
Yes
External flash metering Yes
Manual flash 1/1 - 1/128
Multi flash 1/4 - 1/128
1 - 500 Hz
(1 - 199 Hz with optical wireless)
1/4 - 1/128
1 - 199 Hz
First-curtain /
second-curtain sync
Yes
High-speed sync Yes
FE lock Yes
Exposure compensation ±3 stops
White balance adjustment Color temperature information transmission Yes
Color filter Yes No
Firing features FE lock Yes
Exposure compensation Yes
FEB Yes
Wireless slave feature Radio wireless Yes No
Optical wireless Yes
Display panel 104 x 172-dot display Fixed-segment display
AF assist beam Supports 1 to 61 AF points Supports 1 to 45 AF points
Custom functions 18 14
Personal functions 7 0
Internal sound generator Yes No
Power supply Unit power supply Four AA alkaline batteries
(Also accepts Ni-MN and lithium batteries)
External power supply CP-E4 compact battery pack
Recycling time
(when using AA alkaline batteries)
Approx. 0.1 - 5.5 seconds
(Quick flash: approx. 0.1 - 3.3 seconds)
Approx. 0.1 - 5.0 seconds
(Quick flash: approx. 0.1 - 2.5 seconds)
No. of flashes 100 - 700
Dimensions (w x h x d) [mm]
(not including the dust-resistant/
water-resistant adaptor)
79.7 x 142.9 x 125.4 76 x 137 x 117
Weight (unit only, no batteries)
[approx., grams]
425 405

Table 2: Main specifications of the 600EX-RT and the 580EX II