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C300 mkIII - Did I get a lemon?


I bought a C300 mkIII new in January, and I'm already having some weird issues. I'm curious if anyone else is dealing with these problems:

-SD card slot inconsistencies – For the first four days of a 6-day shoot, we recorded proxies to an SD card with no issues. Then, suddenly, the camera would not initialize that card. We switched to another card with no problem. Then a week later, SD cards are being formatted (including the problematic one), but nothing is being recorded to any SD card. There is no indicator on the LCD that an SD card is present. The cards, when formatted, are now not numbered, but simply labeled "CANON." And the options to set the sub record format are greyed out. SD card access LED flashes briefly when I close the card slot door, but then immediately goes off.


-SDI output inoperable – I have been unable to get a feed from the SDI output, though it is enabled in the menus. We have tried all the various SDI settings with no avail.


-120fps data rate – this is more of a question than a possible issue. I can't find anything in the literature that indicates a lower bit rate at 120fps RAW, but the record times would suggest this is the case. The LCD still indicates that I am in 4K RAW, there is no sensor windowing, yet record times go UP when switching from 96 up to 120. Why?



UDPATE: A system reset cleared up the SD card issue. It's a little disconcerting that I might have to do that in the middle of a shoot day, though. Hopefully a future firmware update will address this.

To help with any future setup after a reset, you could save off your current settings to an SD card.  See page 132 of the User Manual for details.


EOS 5D IV, EF 50mm f/1.2L, EF 135mm f/2L, 600EX-RT (x6), ST-E3-RT
EOS C70, RF 24-70 f/2.8L IS, EF-EOS R 0.71x

That's exactly what I plan to do. I'll probably do it before today's call, in fact.