BLACKMAGIC RAW
LEFT The incredibly affordable Ursa Mini Pro is made even better as it will have Blackmagic’s own BRAW Raw codec added as well as conventional CinemaDNG once you are in the grade. CinemaDNG is still an available option on the camera, but I can’t see why you would ever use it. As well as the metadata contained in the Raw file itself, any software built with the Blackmagic technology will be able to generate and process sidecar metadata files. Opening a Raw clip in this software will automatically create the sidecar file, which stores details of, andmodifications to, the Raw settings that youmake. For instance, perhaps you change the ISO. The Raw file still contains the ISO information from the camera at the time of shooting, but the value in the sidecar file will take precedence in any Blackmagic Raw-enabled software. So, if youmake a change, that change will be seen when the clip is opened again in DaVinci Resolve. It’s non-destructive, of course. Interestingly, if you shoot Ultra HD at 25fps at compressions of 5:1 or higher, you can record on to a Class 10 U1 SDHC card. Youmight, for instance, shoot all the general rushes on cheap SD cards, and keep a couple of more expensive CFast cards for slomo. The URSAMini Pro has a toggle switch to change between card types, so both can be loaded in the camera. Image quality with all the codec settings is excellent. With a well-lit, bright scene it is hard to tell the difference between the compression levels – they all seem to produce equally great results. However, when you get a situation where there is shadow detail that needs to be brought up in the grade – and that may be why you are shooting BRAW in the first place – the compression setting you choose will have some impact. Q5 compression shows more noise in the shadows than Q0, though (oddly) the sensor’s fixed pattern noise was more obvious in Q0, as perhaps the raising of the overall noise floor in Q5 masks the
back quite happily on a MacBook Pro with no hardware decoder boards or external GPUs. I even tried it on a 2015 MacBook Pro with absolutely no issues at all. To encourage other software manufacturers to support its Raw files, Blackmagic has released a software developer’s kit onMac, Windows and Linux. BRAW is compressed with two options: the first produces a constant bit rate (CBR) and offers compressions of 3:1, 5:1, 8:1 and 12:1. The second is a variable bit rate with two settings. Q0 reduces data to between about 20%and 50%of uncompressed, while the Q5 setting gives a reduction of around 8% to 20%. Compression sounds like a bad idea, but it’s generally better done on the sensor data than on 4:2:2 image data, which has already been processed heavily. You need twice as much compression on 4:2:2 data as you do with Raw, plus you will have introducedmore artefacts by de-Bayering and then compressing. In practice, even with the 12:1, CBR codec compression artefacts are very hard to spot in real-world images. I’m told that Blackmagic may introduce some higher compression ratios in the future, but as it stands I would be happy with 12:1 for general shooting – it produces very manageable file sizes. The variable bit rate codecs are also excellent. Hypothetically, Q0may produce a data rate that is faster than the recording media can cope with. When using this setting, don’t even think about using the SD card slots (though they are fine for 8:1 or 12:1 CBR). With decent CFast cards, this is only likely if you are shooting 4.6K
at 60fps. The camera still lets you select Q0 at high frame rates, so it’s up to you to decide whether you want to take the risk. Personally, I think that’s the right decision. If the action can be repeated, why not try Q0? If it can’t, stick to Q5 or CBR. Blackmagic’s URSAMini Pro has always been capable of producing excellent images with CinemaDNG, but you had to work to get the best result. The new BRAW simplifies the workflow. Images look great withminimal work in DaVinci Resolve and, of course, you have lots of flexibility “I even tried it on a 2015MacBook Pro withno issues at all”
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