Rethinking Raw: Postproduction Possibilities for the Blackmagic Cinema Camera11/20/2012 7:18 AM Eastern
Digital camera development has been running in high gear for several years, outpacing any other portion of our industry. Thanks to a revolution started by RED, Nikon and Canon, videographers are now blessed with a wide range of small, affordable, high-performance imaging systems that have liberated us from the restrictions of the mundane 2/3” video camera.
Lightroom and Aperture each offer extensive control over color and image enhancement, making them ideal alternatives for looks creation.
The newest entrant is the Blackmagic Cinema Camera (BMCC), introduced by the industry’s favorite disrupter, Blackmagic Design. The camera is distinguished by its small form factor, QuickTime or camera raw recording and a $3K price tag.
The basic engineering design of the Blackmagic Cinema Camera is a “sandwich” of an EF or MFT (Micro Four Thirds) lens mount, a recording device based on the HyperDeck Shuttle and a touchscreen/viewfinder. It records either 1920 x 1080 ProRes HQ QuickTime movie files or 2400 x 1350 CinemaDNG camera raw image sequences. (Version 1.1 software was recently released, which adds Avid DNxHD support.) The high-def QuickTime files are downsampled from the 2.5K sensor. With CinemaDNG selected, each clip is treated as a folder of individual frames, plus a Broadcast Wave file. Each time “record” is pressed, the camera creates a new folder for that clip. The camera raw files maintain the full sensor resolution, allowing for high-quality reframing and digital zooms in post.
This isn’t a camera review, so I’ll leave the discussion of the merits of the camera in the field to others. Since the BMCC offers new options to filmmakers, it’s important to understand how to handle these files in post.
Understanding Camera Raw
CinemaDNG image sequences can be imported into After Effects and adjusted using the camera raw importer. Additional color correction may be performed with plug-ins like Magic Bullet Looks, as well as built-in tools like the curves control.
Camera raw is not an acronym. The term “raw” refers to a file that has not gone through full processing to produce a final RGB image. The full dynamic range of the sensor’s ability to capture light is maintained in raw images. Different manufacturers use different camera raw methods and profiles for individual models. When you get frequent software updates to Apple Aperture or Adobe Photoshop, it’s often to add new camera profiles to keep current with the latest Canon or Nikon offerings. In most camera raw images, ISO/exposure and color temperature/tint values are represented as metadata recorded by the camera at the time the image is captured. As metadata, attributes can be altered in post and changes aren’t “baked in” as a permanent part of the image as they would with a .tiff or .jpeg still. If a camera raw image appears to be slightly overexposed, post processing software allows you to recover the highlight detail by changing the ISO or exposure values.
Adobe launched an initiative to create a common camera raw format as a type of “digital negative” file, which became the DNG standard. This was released as open source software and is available for manufacturers to use in their products as DNG (stills) and CinemaDNG (motion), thus eliminating the need for them to create new, proprietary camera raw file formats. Blackmagic uses the CinemaDNG file format for its raw image sequences, which means that a wide range of applications can read, open and import these files natively. Those that include camera raw importer modules also enable you to alter the recorded settings within that application.
Correctly importing camera raw images is important. For instance, Apple Final Cut Pro X will natively read the BMCC’s CinemaDNG files, but it currently has no raw importer settings. If the “as shot” metadata makes the image appear overexposed with clipped highlights, you cannot recover that detail from within FCP X. Likewise, not all camera raw importers use the same values. An image opened with the default or “as shot” values in DaVinci Resolve will look different than in an Adobe application. The beauty of the raw format, though, is that the image is within an adjustable range, and any of these importers will give you good results with a few tweaks.
Image Sequence Workflows
Blackmagic Design includes a full copy of DaVinci Resolve 9 with the purchase of the camera, and that’s obviously their recommended tool for producing “dailies” and final color correction. Since DNG is a still photo format, grading and conversion can be handled in other applications, too, including Adobe Photoshop, Photoshop Lightroom, Adobe After Effects and Apple Aperture. Each of these applications includes camera raw controls to get the most out of the image. Currently you cannot import the camera raw files directly into Avid Media Composer, Apple Color or Adobe Premiere Pro. Adobe SpeedGrade (with the latest updates) will read the files but offers no specific camera raw adjustments. There, the default import of CinemaDNG files renders a flat, log-style image as a starting point.
The following is a simple workflow based on a photography application such as Lightroom or Aperture. Import each folder of CinemaDNG files into the application. Now select a representative frame within that group and apply your adjustments. Since these are full-featured color correction tools, go as extreme as you like if you intend to create the final look at this time. Once you get the appearance you want, copy-and-paste those settings to the other images in that folder. These are non-destructive changes within Lightroom and Aperture and may be altered at any time. Export the adjusted versions as a new set of .tiffs to a separate folder on your hard drive. These .tiffs will contain the “baked in” look you have just created.
|Make sure the application you use allows adjustment of the camera raw metadata in order to recover the actual dynamic range. This example shows the imported image in FCP X using the “as shot” data, as compared with an adjusted image in Photoshop.|
The process is a bit different in Photoshop, but there you have the option of using one of the many special tools and filters to create unique looks. For example, you can apply an oil paint or dark strokes effect for an artistic, painted style. Open a representative frame from a shot and apply the settings you want to use. As you do this, record the steps as a Photoshop action. When you are happy with the look, use Photoshop’s batch function to apply this saved action to all the frames in a folder for each shot.
The CinemaDNG files are 5 MB/frame in size, while the exported .tiffs are 9.8 MB each. It is possible to open a .tiff image sequence in QuickTime 7 and save it as a QuickTime reference movie, which, in turn, can be used as an editing source in Final Cut Pro 7 and X. If you update the files later by re-exporting .tiffs with a new look, the reference movie will be updated to reflect the change. FCP X offers a performance edge by being able to play these 2.5K sequences natively in real time within a 2K or HD timeline. QuickTime reference movies are 8-bit, but I saw no visual difference when comparing these files to 10-bit uncompressed and ProRes 4444 exports. I would recommend that you transcode these to proxy editing files in FCP X if you opt for the QuickTime reference method.
After Effects offers another solution. You can open CinemaDNG image sequences, make adjustments with its camera raw importer, and then render out final, graded movie files. Naturally, plug-ins like Red Giant Magic Bullet Looks add more options for custom styles. If you opt to first convert the DNG sequences to .tiffs using Lightroom or Aperture, then Avid Media Composer and Symphony will auto-detect the files as an image sequence and import them as a single media file.
DaVinci Resolve 9
|DaVinci Resolve 9 includes a new camera raw tab. First import the image sequences and adjust the camera raw values before starting to grade the shot.|
DaVinci Resolve 9 is an advanced grading tool, but it may be used simply to turn the image sequences into a set of flat-looking QuickTime movie files suitable for color correction later. Resolve 9 now includes a camera raw settings tab. Tweak the settings and then export each clip as a separate movie file. Blackmagic Design has implemented BMD Film with this camera. BMD Film is a log-encoded color space and gamma profile that resembles ARRI’s Log C. This profile may be selected in-camera for the QuickTime files, but may also be used as a preset in the Resolve 9 raw module (also available in the free Lite version).
So far my testing has been limited to the handful of clips by Australian DP John Brawley. These are sample shots from the short film “Afterglow,” which was produced to showcase the capabilities of the Blackmagic Cinema Camera. Brawley has posted several shots online in both CinemaDNG and ProRes HQ formats. The QuickTime files from the camera were encoded with the BMD Film profile, which matches the same setting when applied to camera raw files converted through Resolve 9.
|In this Photoshop example, the look was created using the camera raw import settings, the Photo Filter adjustment (warming filter) and curves.|
The option of using After Effects, Photoshop, Lightroom or Aperture gives users an interesting new toolset for creating stunning images, but for most there’s a comfort factor in using your favorite NLE or grading software. I believe the majority of users will probably stick to shooting ProRes HQ files using the BMD Film log profile, because it’s a proven workflow. It preserves the dynamic range and gives you most of the latitude available from the CinemaDNG files. Camera raw files exported from Resolve 9 as ProRes HQ using the BMD Film preset (without other correction) are identical in appearance to the QuickTimes recorded in-camera. The ARRI Alexa also shoots raw and Log C, which makes the BMCC an interesting option as a sort of “baby Alexa.” I haven’t intercut clips from a project that was shot with both an Alexa and the Blackmagic camera yet, but I suspect the BMCC would work well as a B or C camera in this type of production.
When I take the BMD Film-encoded clips into Final Cut Pro 7 or X, the values are close enough to Log C that I can use many of the same LUTs and filters. For example, the Pomfort Alexa Look2Video filter that I use to correct Log C into Rec. 709 works equally well with BMD Film. I’ve done grading tests using a range of NLEs and color correction software and have been very impressed with the results from these Afterglow test clips. Working with the CinemaDNG or ProRes HQ BMCC clips will fit into established workflows, without the need to learn new, proprietary tools. No matter what your preference—Avid, FCP X, Premiere, After Effects, Color, Resolve, Photoshop, etc.—this is one new camera that was designed with post in mind.