There are a couple of reports right now of users managing to overcome the overheating limits of the Canon EOS R5 mirrorless camera. Well, sort of. By tricking the camera into thinking the battery slot door is closed when it’s not, people have found a way to reset the timer. But there’s a catch. Your footage is pretty much useless.
The video above by J. Marcus Photography demonstrates the technique, and how he was able to reset the timer using just a piece of tape over the battery door to make the camera think it was still closed. When the overheat warning came on, he removed the battery, reinserted it and magically the overheat warning was gone.
Andrew Reid over at EOSHD also performed a similar experiment, wedging a small screw into the slot to achieve the same result as the tape and managed to record 8K video almost continuously for 51 minutes.
These experiments (non-scientific, but I don’t think there’s a better word) definitely seem to reinforce the belief that the time limits placed on shooting video with the EOS R5 are artificially imposed by Canon and have nothing to do with the actual temperature of any part of the camera. The big issue with this technique, though, is that you have to do it while the camera’s still recording.
The leading theory at the moment is that the camera stores some data into its firmware or other internal storage that keeps a log of when the overheat warning kicked in and when it’s set to expire. The camera doesn’t write out this data continuously, though and certain acts seem to force it to happen. Like when you open up the camera’s battery door or stop your recording.
The key with this trick is not giving the camera any warning or chance to write out the data. If the camera thinks the battery door is shut when it’s not, then it never sees it open. And if you don’t hit stop on your recording, again, it doesn’t know to save out the data. So, when you just pull the battery, nothing is written out and the camera has no idea it just had an overheat warning.
While it does sound promising it’s not a fully workable solution. For a start, because the file is never closed gracefully, it’s essentially unusable. And who wants tape or a screw hanging off the bottom of their camera while they’re shooting a gig?
But it does back up the idea that the time limits artificially imposed can easily be overcome any time Canon chooses to do so. If they ever choose to do so.
Whether or not some clever programmer can write a recovery application to pull data from those not-properly-closed clips and write out a new clean file, I’ve no idea.