Wireless Transmitter
Canon Speedlite Transmitter ST-E3-RT (Ver.2)
SpecificationsSpecifications
-   Radio frequency remote flash trigger
 -   Fire selected Speedlites from 30m away
 -   Part of the E-TTL II flash system
 -   Controls up to 15 flashguns
 -   Remote camera triggering
 -   Weather sealed against dust and moisture
 -   Second curtain sync, 1/8192 power and FE memory for EL-1 and later Speedlites
 
Specifications in detail
Flash Modes
- Auto Exposure ControlE-TTL II / E-TTL
 - High Speed Sync (FP)Yes
 - Manual / Output Settings
 - Manual Steps1/3 step
 - Strobe / Output Settings
 - Stroboscopic Frequency1-500Hz
 
Flash-Related Function
- FE LockYes
 - FE Memory
 - Flash Exposure CompensationYes
 - Flash Exposure BracketingYes
 - Second-Curtain Flash Sync
 - Modelling FlashYes
 
Wireless Flash
- TransmitterYes
 - Transmission TypeRadio
 - Transmitter RangeIndoors: 30m
Outdoors: 30m - ReceiverNo
 - Number of Groups5 - A,B,C,D or E
 - Number of Channels15
 - Remote Shutter ReleaseYes
 
AF Assist
- AF-Assist BeamNo
 - Number of AF Points Supported-
 - AF-Assist Beam Type-
 
Power Source
- Battery2 x AA batteries
 - Minimum Recycling TimeN/A
 - External Power SupplyNo
 
Construction
- Dust and Water ResistanceYes
 - Mounting Foot MaterialMetal
 
Miscellaneous
- Custom Function8 (4 personal functions)
 - Flash Settings from Camera MenusYes
 - External Flash Exposure SensorNo
 - PC TerminalNo
 - Accessories (Included)Soft case
 - Accessories (Optional)Off-Camera Shoe Cord OC-E3, Release Cable SR-N3
 - Compatible SpeedlitesEL-1, 600EX II-RT, 600EX-RT, 430EX III-RT
 
Physical Specifications
- Dimensions (W x H x D)67.4 x 61.5 x 77.4
 - Weight110g
 
- Compatible cameras may need the latest firmware update.
 - Minimum flash output of 1/8192 possible with Speedlite EL-1 only (1/128 with high-speed sync). Does not show in the camera's UI settings on cameras launched before 2020.
 - Compatible cameras may need the latest firmware update.
 - Minimum flash output of 1/8192 possible with Speedlite EL-1 only (1/128 with high-speed sync). Does not show in the camera's UI settings on cameras launched before 2020.
 - Compatible cameras may need the latest firmware update.
 - Flash output amount may slightly differ between that of E-TTL autoflash and manual flash
 - Compatible cameras may need the latest firmware update.
 - With compatible cameras launched from 2020, e.g. EOS-1D X Mark III, EOS R5/R6 and later, but excluding EOS 850D.