On this write-up, we check out the brand new encoding choices that include Blackmagic RAW: fixed bitrate and fixed high quality.

Earlier this 12 months, Blackmagic Design retired the CinemaDNG format from their digital camera line (not you, URSA Mini 4.6K) and changed it with Blackmagic RAW. The brand new codec affords some thrilling options to the BMD digital camera lineup. We’ll have a look at the specifics at a later date; nevertheless, Fixed Bitrate affords 4 encoding choices: 3:1, 5:1, 8:1, and 12:1. And Fixed High quality affords two high quality settings: Q0 and Q5. What do these new settings imply? Let’s have a look.


Fixed Bitrate

Fixed Bitrate is Blackmagic RAW’s providing to verify your file sizes stay predictable and manageable as a result of your media is rarely going to surpass the chosen information charge. Low on card storage however have loads to seize? Setting the RAW encoding to eight:1 will be sure that the info is not going to surpass 50MB/s. (The ratios, by the way in which, are derived from the file measurement of a single, unprocessed body from the digital camera’s sensor.) Whereas Fixed Bitrate is a surefire setting, to verify the file sizes and high quality will stay as marketed, it might trigger points when the footage being captured might do with out the additional compression, making certain that each one particulars of a busy scene are clear. Such examples embody confetti, snow, bustling bushes, and something with a excessive variety of interconnecting, transferring objects. The system might want to alter for extra element, however it could’t as a result of the knowledge to account for that is unavailable, which leads to a drop in high quality.

Picture through Blackmagic.

Likewise, it’s possible you’ll be recording one thing that doesn’t want a excessive bitrate, however as a consequence of this encoding, the digital camera will proceed to seize footage that might have been captured at a considerably smaller file measurement.


Fixed High quality

Fixed High quality, alternatively, has a variable bitrate with no higher information restrict. This implies in case you’re filming a marriage and the company begin throwing confetti and rice, and extra objects enter into focus, the bitrate will alter to account for the rise in complicated body info, sustaining the general high quality of your complete picture. In fact, this comes with bigger file sizes which you can’t predict.

Word, nevertheless, that the drop in high quality between the 2 encoding choices and between the assorted choices is, in fact, minimal. It’s not as in case you’re dropping from 4K to 720p. The distinction in picture information, at most, is just going to be seen at a zoomed-in stage, and the discrepancy in high quality will probably be yours to guage in your content material. Within the photographs under, are you able to inform which photograph was shot at Fixed Bitrate 12:1 and Fixed High quality Q0?

Picture 1

BMPCC4K Tips: The Difference Between Using Constant Bitrate Vs. Constant Quality - BMD RAW

Picture 2

BMPCC4K Tips: The Difference Between Using Constant Bitrate Vs. Constant Quality - BMD RAW

Okay, each stills are solely 755 x 400. It could be powerful to check, however on the floor, there isn’t a noticeable distinction. It’s solely after we zoom in at 225 % that we will see the extent of element disregarded at 12:1. Even then, at 225 %, it’s not horrible.

BMPCC4K Tips: The Difference Between Using Constant Bitrate Vs. Constant Quality - BMD RAW Comparisons

We are able to see the picture element holds much less readability, which might be extra predominant within the flowers and foliage. Ideally, we would wish a video comparability to correctly present this. Within the following video from LumaForge, Patrick Southern demonstrates (utilizing video) an instance of the encoding distinction — together with additional deconstructions of the Blackmagic Uncooked Encoding. However nonetheless, we have to acknowledge that on the lowest 4K RAW setting, that is zoomed in at 225 % and nonetheless holds up nice.

Deciding easy methods to shoot finally comes right down to what you’re filming. Visible results (VFX) plates and scenes with bustling info needs to be shot at Fixed High quality, whereas components that preserve related picture values all through your complete scene could be shot at a Fixed Bitrate.


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