The YONGNUO Speedlite Transmitter YN-E3-RT is a transmitter for wireless flash flash shooting. It can control up to 5 groups (15 units) of Speedlites that have a wireless mltiple flash shooting function using radio transmission.

The transmitter also has dust and water resistance equivalent to EOS-1D series cameras.

Functions:

• #1, Two-way 2.4G radio communication, fuly campatible with ST-3E-RT/600EX-RT
• #2, 15 Physical Channels, 1 Auto Channel, Up to 10,000 customizable photographer ID
• #3, Transmission Range: 100M
• #4, Multi YN-E3-RT can share slave flashes
• #5, Display group/charge status of slave flashes
• #6, Firmware can be upgraded via USB
• #7, High resolution Dot-Matrix LCD, Backlight for LCD/keys
• #8, Fast lock mechanism
• #9, Built-in AF assist beam emitter, buzzer
• #10, Remote shutter release, Linked Shot (Need extra shutter cable for cameras released before 2012)
• #11, Flash Mode: ETTL/M/Multi/GR 4 flash modes
• #12, A/B/C/D/E 5 groups
• #13, Supports 1st Curtain, 2nd Curtain (Only in M mode), High speed Sync
• #14, Supports ETTL Ratio, Flash Exposure Compensation, Flash Exposure Lock, Flash Exposure Bracket, Modeling Flash
• #15, 9 Custom Functions
• #16, Settings saved automatically

Specifications:

• Type: on-camera Speedlite transmitter
• Compatible cameras: EOS type-A camra compatible with E-TTL II/E-TTL autoflash
• Exposure control system: E-TTL II/E-TTL autoflash, manual flash, stroboscopic flash, auto exteral flash metering ** only when the flash mode is set to <GR>
• Frequency: 2405-2475Mhz
• Modulation system: Primary modulation: OQPSK, secondary modulation: DS-SS
• Channel: Auto, Ch. 1-15
• Wireless radio ID: 0000-9999
• Slave unit control: Up to 5 groups(A/B/C/D/E), up to 15 units
• Transmission distance: Approx. 100m
• Flash ratio control: 1:8-1:1-8:1, 1/2-stop increments Flash exposure
• compensation: +3~-3 stops in 1/3 - increments
•                        +3~-3 stops in 1/3 - increment(when used with flash exposure compensation)
• FE Lock: Press the camera's <M-FN>, <FEL> or <*> button
• High Speed Sync: Provided
• Manual Flash: 1/1-1/128 power (1/3-stop increments)
• Stoboscopic flash: Provided (1-500Hz)
• Flash exposure confirmation: Flash exposure confirmation lamp lights
• Modeling flash: Fired with camera's depth-of-field preview button
• Linked shooting: Provided
• Custom Functions: 9
• AF assist Beam Emitter: Provided
• Firmware update: Provided
• Power Source: 2 AA/LR6 alkaline batteries Ni-MH batteries
• Wireless flash shooting time: Approx. time: 10 continuous hours ** when using AA/LR6 alkaline batteries
• Power saving: Power off after 5 min. of idel operation
• Weight: Approx.110g(transmitter only, excluding batteries)

Version 1.10:

http://www.eachshot.com/media/helpdesk/attachments/as-713/3262/YN-E3-RT_FW_V1.10.dfu

Fixed: couldn't set fec of group b/d via camera menu.

Version 1.09:

Fixed: update limit of flash number in Multi mode.
Fixed: disable HSS in multi mode
Added: P.FN: legacy trigger mode. When it's set, YN-E3-RT won't detect ettl
input so that it can be used on Fuji hotshoes.
Added: P.FN: Free Mask Group. This setting is used with GR/*. Free mask will
be on/off when you hold GR/* button for a few seconds. When Free mask is on,
groups not in this setting won't fire. So you can take a photo with background
flashes only quickly.

Version 1.08:

Fixed: correct ettl2/gr exposure for 1D-X.
Fixed: improved light metering for cameras after 2012.

Version 1.07:

Fixed: When one of the group is set to ETTL mode, if one of the flash is not
recycled, it may make a full output flash due to incorrect light metering. Now
YN-E3-RT won't trigger a flash in such a situation. Note: if the group is set
to M mode, a flash will be triggered no matter it is recycled or not.

Fixed: improved flash syncing with cameras after 2012.

Added: Legacy flash trigger (for non canon cameras). Now you can use YN-E3-RT
on non canon cameras with standard iso hot shoe. You need to press test the
test button to transfer the M mode parameters.

Version 1.06:

Fixed: Incorrect Exposure for GR mode on cameras before 2012, when one of the group is set to M mode.
Added: Version information display on menu4.

Version 1.05:

Fixed: Compatible issue with 5D Mark III/6D/70D/650D.

Package Includes:

• YongNuo Speedlite Transmitter YN-E3-RT x 1
• Manual x 1