While I am new on these forums I have been on the Canon Rumors Forums for a few years now,
I really wanted to bring this too the attention of you and Canon as it is simply a highly important problem, those of you that don't know, the 5D3 suffers serious focus locking issues when a Canon speedite is attached in Low light, the AF assist beam causes lag with the AF from the 5D3, this makes it virtually impossible to achieve focus in low light when the speedlite is attached, I wanted to bring the topic to this forum, so I have pasted a link to all the discussion we have already had about this problem at Canon Rumors.com - see below
Please help in letting Canon know this is a very serious problem and effects the cameras performance in most working environments when a speedlite is attached and working in low light, conferences, nightclub work, weddings etc, and can stop the photographer completing the job or task.
Hi steliosk! Since the 600D is not manufactured for use in the United States, Canon USA doesn't have any information on any issues it may encounter. If you're having issues with your specific product, and live outside of the United States, please click here and select your country or region for your support needs. We encourage you to discuss Canon products sold outside of the United States, but please be aware that you will not receive support directly from Canon USA.
We have an update on this topic. A firmware update for the EOS 5D Mark III has just been released. Firmware Update Ver. 1.2.1 incorporates functional improvements and fixes including uncompressed HDMI output, Center AF point to auto-focus at f/8 when used with Canon EF lens/extender, and AF speed improvement when using the Speedlite’s AF-assist beam.
To learn more and download the update, click here .
Thank you very much to everyone at Canon for this, there is no mention on the website that this firmware incorparates the assist beam fix?, but Im assuming it does, I will install it later, would like to hear what others have to say,
Just a big thanks to everyone at Canon for listening to the Forums and helping us make this camera even more perfect,
all the best
Thank you again Canon
Here is the list
A list of improvements in firmware version 1.2.1 is listed below.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.