Canon USA has issued a product advisory to owners of the Canon Speedlite 600EX-RT flash and ST-E3-RT wireless transmitter.
The company has discovered that with certain units, wireless flash shooting with radio transmission will not work in some setting modes when 7 or more units are linked.
Photographers owning one or more of the affected flashes and/or transmitters are encouraged to contact Canon to have their unit(s) inspected and serviced for this phenomenon at no cost.
Speedlite 600EX-RT and Speedlite Transmitter ST-E3-RT Firmware Notice
Thank you for using Canon products.
Phenomenon
Except as described below, the following will occur with the affected units listed below:
Linked shooting and wireless flash shooting with radio transmission will not work in some setting modes when 7 or more units are linked. This phenomenon does not occur when 6 or fewer units are linked.
Affected Products
Speedlite 600EX-RT and Speedlite Transmitter ST-E3-RT
Units with a combination of 3rd and 4th digits in the serial number in the ranges shown below are affected:
Speedlite 600EX-RT: [xx01xxxxxx] ~ [xx13xxxxxx]
Speedlite Transmitter ST-E3-RT: [xx01xxxxxx] ~ [xx03xxxxxx]
Note: If the battery compartment of an affected unit contains the marking illustrated below, the product is NOT affected by the phenomenon described above, even if the serial number is within the ranges mentioned above.
Support
To arrange to have an affected unit inspected and serviced for this phenomenon at no cost, please contact Canon using the information below.
This information is for residents of the United States and Puerto Rico only. If you do not reside in the USA or Puerto Rico, please contact the Canon Customer Support Center in your region.
Thank you for using Canon products.
Customer Support Operations
Canon U.S.A., Inc
Contact Information for Inquiries
Canon Customer Support Center
Phone: 1-800-OK-CANON
1-800-652-2666
TDD: 1-866-251-3752
Email: carecenter@cits.canon.com
For additional support options: usa.canon.com/support
