Sound to Camera – Black Magic Cinema Camera

I plan on working on a few things where one or two Black Magic Cinema Cameras (BMCC) are to be used in the near future, so I have got hold of one of the cameras to test out audio on it. A lot of video people seem quite excited about these cameras – they are fairly affordable and pack in 2.5k sensor, high dynamic range (for video), and ability to shoot directly in ProRes or RAW format. So how does it go for audio?

The camera features two 1/4″ TRS phone plug socket inputs. XLR’s would have been nice but too large to fit on the body, and this is still a much better option than 1/8″ connectors as per a lot of DSLR type cameras and some of the RED cameras. There is no phantom power available for powering mics from the camera, which might bother some people, although really using a field mixer or some other kind of unit such as those provided by Beachtek or JuicedLink to supply phantom power and clean gain are going to be a better option anyway.

The biggest issue straight up with the BMCC for audio is that currently, as at Firmware version 1.4, it has no audio meters. Poor form I say. You could plug the camera in to your computer via Thunderbolt, and then calibrate it using the Black Magic Ultrascope software that comes with the camera, but it is still a bit lame that it doesn’t have meters on board.

Speaking of firmware versions, there have been a few released, and audio features and results vary according to the version. For instance, in v1.1 there was a DC offset and a “feature” where if a sustained signal was sent to the camera that was too hot while it was set at Mic input level, the camera would auto-switch to Line level input. That’s a little scary potentially depending on the set up. They have fixed those things in more recent versions but now there is a filter issue so you get far from flat response audio from the inputs. There are work-arounds for these things, but in my opinion they are only workarounds and I would not recommend using the BMCC for single-system sound. I recommend always running dual-system sound with this camera as it currently stands with firmware up to v1.4, although we shall see what the future brings with regards to v1.5 and beyond.

Some other issues include that the preamps are not the greatest quality (the usual thing on cameras), and that they are set with a % rather than any dB scale. Apparently the BMCC uses digital attenuation when setting below a certain setting (around 80% on v1.3 according to http://juicedlink.com/blog/2013/04/blackmagic-cinema-camera-v1-3-audio-tests/) so your signal could be clipping before your A/D but still be below 0dBFS on your recording. That is another good reason to avoid the camera audio in my opinion, although you can supposedly get good results if you are careful with using a mixer or front end preamps and calibrating carefully.

Oh, and the headphone amp is rubbish. Again, no surprise really.

But there is one more thing that really bugs me – fan noise. The camera has very noticeable fan noise, and unlike the RED Scarlet and Epic cameras, you cannot “turn down” the fan speed when shooting. This ruins it for me if you are planning to shoot quiet drama scenes. Depending on where the camera is placed compared to any mics, the mics are likely to pick up fan noise which likely means additional noise reduction in post.

The production I plan on using the BMCC for next is a live video clip at a gig, and I don’t care about the audio to camera too much, but you really should take into account both the limited audio capability and the fan noise when considering whether the BMCC is the right camera to use for your shoot.

BOTTOM LINE: The BMCC might shoot some beautiful footage, but it’s current audio capability as at firmware version 1.4 leaves a lot to be desired. I would recommend running dual-system sound with this camera, and even then, I would recommend against using this camera for shooting quiet, intimate scenes due to the fan noise from the unit. Please consider the poor sound team.

This entry was posted on Friday, September 27th, 2013 at 1:01 pm and is filed under Location Sound. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

 

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