Author Topic: Canon 5D Mark III / 5D3 / Firmware 1.3.4  (Read 14039 times)


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Re: Canon 5D Mark III / 5D3 / Firmware 1.3.4
« Reply #25 on: June 09, 2017, 01:03:29 PM »
Hiya all. I am buying a second hand Mkiii with 1.3.4 firmware installed. I will want to use ML on it, reason why I am reading this post. I am getting that I will need to downgrade it to 1.2.3. Where do I get the downgrade from? And I am not getting the procedure. Can anyone please explain it step by step? Get second card, so that will be after downgrading the camera to 1.2.3?? And how do I then install 1.3.4 if I downgraded the camera? Sorry for being probably a bit slow... :-(

Format card in cardreader.
Downgrade to firmware 1.2.3.
Install ML for firmware 1.2.3.
Use a second card (clean one, format in cardreader, then in cam) and install firmware 1.3.4.
Backup and delete "ML" card's Autoexec.bin, ML-SETUP.FIR and ML directory.
Copy extracted 1.3.4 build contents to "ML" card.
Does it work now?

Report back.


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Re: Canon 5D Mark III / 5D3 / Firmware 1.3.4
« Reply #26 on: June 10, 2017, 11:17:57 PM »

Pelican keeps an archive of Canon firmware updates on his website:

Here are instructions how to do a Canon firmware downgrade:

Just a tip--for the best Magic Lantern experience on 5D3 use 1.1.3, if you need HDMI output and some other updated features use 1.2.3 if you want to live on the bleeding edge and help with development then maybe 1.3.4 is for you.
EOSM.202 EOSM.203 EOSM2.103 700D.115 5D3.*