Specifications

E-TTL requires the use of EX-series dedicated
Speedlites such as the 580EX, 430EX, 220EX,
MT-24EX, or MR-14EX in combination with a
compatible camera.
E-TTL II—Available on Canon’s newest EOS SLRs,
E-TTL II incorporates distance information from
compatible EF lenses (see page 27 for details) for
more versatile flash exposure control. E-TTL II
minimizes underexposure that can occur with
straight reflections by ignoring sensor areas that
report abnormally high levels. This feature is useful
when shooting a subject with a highly reflective
object in the background, or if the subject itself is
highly reflective. In addition, because distance
information is used in calculating the flash output
level, E-TTL II prevents overexposure when
photographers lock focus and recompose.
For example, with the EOS-1D Mark II N, the
ambient light is first measured using the camera’s
21-zone metering when the shutter button is
pressed. Next, a preflash is fired and the metering
sensor takes readings at the central 17 metering
zones. The ambient and preflash readings are
compared. The metering areas having small
differences are selected as the main flash exposure
areas. Areas with large discrepancies between
ambient and preflash readings are excluded or
down-weighted because they are assumed to
contain a highly reflective subject, or the subject
is not in that part of the frame—an assumption
validated by distance information. The algorithm
thus avoids chronic underexposure problems in
such situations. These readings are weighted,
averaged, and compared with the ambient light
reading and the main flash output is then set
and stored in memory.
Unlike previous systems, E-TTL II, in effect, captures
the subject as a “plane” and not as a “point.”
As a result, EOS SLRs can deliver consistent flash
exposures even if the subject contains various
colors and levels of reflection. The camera also
allows the user to select an averaged metering
pattern through custom function settings.
TTL*—TTL (Through-The-Lens) is the standard
flash exposure control mode used by the built-in
flash units that come with some 35mm EOS
cameras. Unlike E-TTL or E-TTL II, TTL reads flash
illumination reflected from the film during the
exposure. When the camera is set to Program AE
mode, TTL flash sets an aperture based on the
ambient light level.
Flash Exposure Lock (FE Lock)
FE Lock adds auto exposure lock and spot metering
functions when shooting with EX-series Speedlites
and E-TTL compatible EOS cameras. The EX-series
Speedlite’s preflash fires when the camera’s AE
Lock button is depressed, storing a spot meter
reading of flash and ambient lighting data for up
to 16 seconds. This provides enough time to not
only recompose the shot, but also alter the ambient
light exposure for maximum creative control. FE
Lock is extremely useful when you wish to
recompose after focus lock or to place the main
subject in a part of the frame not covered by one
of the focusing points. It can also eliminate
potential exposure errors caused by unwanted
reflections from surfaces like windows or mirrors.
Adjusting Ambient Exposure in FE Lock**—After
preflashing the subject with the FE Lock button,
ambient exposure can be adjusted by turning
the Quick Control Dial. The ambient exposure
level is displayed on the exposure level scale in
the viewfinder and on the external LCD panel.
FP Mode***
FP (focal-plane) flash, or High-speed Sync,
enables E-TTL and E-TTL II compatible cameras
equipped with an EX-series Speedlite to synchronize
flash at shutter speeds faster than the camera’s
normal maximum sync speed. Even in bright
daylight, for example, a fast lens can be used at
a wide aperture to reduce depth-of-field and
emphasize the subject. FP flash can be combined
with E-TTL, E-TTL II, or FE Lock, and is available in
all AE modes plus Manual.
Flash Exposure Compensation****
This setting adjusts flash output without changing
the shutter speed or aperture. It’s a particularly
effective way to fine-tune the balance between
foreground and background exposure for fill flash
shots, but it can also be used to compensate for
extremely bright or dark tones in the subject.
Second-Curtain Sync
Instead of firing the instant the shutter opens,
Second-Curtain Sync fires the flash at the end of
the exposure, allowing streaks of light to flow
naturally behind a moving subject. This creative
flash mode is most effective with slower shutter
speeds and subjects with light sources, such as
the headlights of a moving car.
Stroboscopic Flash
Stroboscopic flash is a series of flashes fired in
rapid succession during a single exposure. With
stroboscopic flash, multiple images of a moving
subject appear in the photograph. Using this
mode, you can analyze a golf swing or record
the shattering of a windowpane. (Available with
Speedlite 580EX, Macro Ring Lite MR-14EX and
Macro Twin Lite MT-24EX).
Integral to the EOS System, Canon Speedlites are the
ideal flash source for EOS SLRs. They are tech-
nologically advanced to provide perfect exposure
and illumination with just about any subject, yet
operation is remarkably simple. Whether you’re a
amateur or an expert, Canon Speedlites make it
easy to obtain professional results.
SPEEDLITES
31
SPEEDLITE TECHNOLOGY
Sophisticated Flash Control Modes
E-TTL—In E-TTL (Evaluative Through-The-Lens)
flash exposure control mode, meter readings
are taken through the lens, but not off the focal
plane. Using a preflash fired after the shutter
button has been fully depressed—but before the
camera’s reflex mirror goes up—E-TTL uses the
camera’s evaluative metering sensor to compare
the ambient light values with the light reflected
from the subject by the preflash. The camera then
calculates and stores the flash output required
for optimum exposure of the main subject (as
identified by the AF point) and the background.
Camera Model
EOS-1Ds Mark II
EOS-1D Mark II
N
EOS 5D
EOS 30D
EOS Digital Rebel XTi / XT
EOS-1
V
EOS-3
EOS ELAN 7
NE
EOS Rebel T2 / T2 Date
EOS Rebel K2 / K2 Date
E-TTL II
Yes
=
Yes
=
Yes
=
Yes
=
Yes
=
No
No
Yes
Yes
No
E-TTL
No
No
No
No
No
Yes
Yes
Yes
No
Yes
A-TTL / TTL
Not Possible
Not Possible
Not Possible
Not Possible
Not Possible
4-point/3-zone
4-point/3-zone
4-point/3-zone
Not Possible
4-point/3-zone
580EX
430EX
220EX
MR-14EX
MT-24EX
E-TTL / E-TTL II
Yes
==
Yes
==
Yes
==
Yes
==
Yes
==
A-TTL
No
No
No
No
No
TTL
Yes
===
No
Yes
===
Yes
===
Yes
===
Manual
Yes
No
No
Yes
Yes
SLR Compatibility
Speedlite Compatibility
=
Not Linked to AF point.
==
Requires EOS body that supports E-TTL and E-TTL II respectively.
===
Defaults to TTL in all conditions except direct flash in the camera’s Program mode.
* A-TTL and TTL are not compatible with digital SLRs. See lens
chart for a listing of lenses that supply distance information.
** Ambient exposure cannot be adjusted when the camera is
set to Bulb mode or in low-light situations when the camera
is set to Program AE or A-DEP.
*** Unlike conventional electronic flash, FP flash output (guide
number) decreases as shutter speed increases above normal
X-sync speed.
**** Flash exposure compensation can be set with most current
Speedlites, and it can also be set with all current EOS
cameras other than the EOS Rebel series and EOS Digital
Rebel.
High-Speed Sync — EF 135mm f/2.0L USM lens •f/2 •1/750 sec.
Taken with MT-24EX and EOS-1v HS