5 Things You Need to Know About CinemaDNG
CinemaDNG is not new, but only recently has it become one of cinema’s hottest talking points. This open source RAW format has not only been adopted by the Blackmagic Cinema Camera and Digital Bolex – both of which created a stir this past year with their studio-quality images at indie-affordable prices – but has also been officially embraced by big-leaguers such as Aaton with their Penelope Delta.
But with all the buzz about who and when, and how, and why, filmmakers who are new to CinemaDNG may be left scratching their heads and wondering how to make sense of it all. What is CinemaDNG and why is it important? Why is this new string of letters creating such a stir among editors and why all this talk about new workflows and even new software?
1. It’s RAW
Film cameras capture pictures more or less directly via a photo-chemical process. Digital cameras do not. Instead, they use light to generate electrical signals at the image sensor. These signals are then translated into digital bits, which must then be organized and packaged in such a way that they can be stored, shipped, and opened by another program as a video file (i.e. your non-linear editor, or NLE).
Think of this process as an assembly line. The CEO (the incoming light) determines what’s going to be made. The Plant Managers (the electrical signals) give the orders to make the product, which the workers in the plant (the pieces of the image sensor) do. The product is digital bits – millions and billions of them. But on this product is a big label: “Some Assembly Required.” The bits by themselves are useless. They must be assembled into packages to keep the right bits together and organized, then reassembled into a video by the end user (your computer software).
To aid in the file delivery, a big book of instructions is often written on how to fit an immense number of bits into a small box (the file). These instructions are called the file’s encoder and the process is called encoding. Most encoders simply throw out large numbers of bits and instead include instructions on how to recreate them later using the existing bits as reference points to aid in interpolating what those missing bits probably looked like. The instructions on how to recreate those bits and assemble the video is called the file’s decoder and the process is known as decoding. The encoding and decoding information is usually contained in a single “instruction manual” which is called the file codec. Most file formats are lossy because their codecs “lose” (purposefully get rid of ) information and try to recreate it later so the video can be reassembled. The advantage of lossy file formats is that you can get a lot of information into a small file, which is able to be easily stored, watched, and edited.
However, the downside to this, as you may have guessed, is that the codec never recreates those missing bits perfectly. Plus, since every time you recompress or alter the file you lose more information, when you start with too little, the end result can be pretty sad. This is why many professionals like RAW files.
RAW files are lossless, which means their codecs hardly throw out any bits. The result is an immense file that is bulky to store and hard to play back and edit, but which contains pristine video with lots of latitude for future manipulation.
RAW files are one reason why cameras such as the RED, BlackMagic, and Digital Bolex are able to deliver such high-quality video. It’s a wonderful thing to be able to shoot RAW, which is why CinemaDNG is an important format to keep an eye on (even with its drawbacks, which we’ll discuss in a minute).
2. It’s Open Source
Most file formats are proprietary, which means that once you invest in a camera, you are locked into using their products forever. Take RED for example. Their RAW file is R3D, which is a format they developed and licensed (think of it as designing the box and writing the instruction manual, then getting a patent and a copyright). If you want to use the RED camera, you either have to use their software (installed with their codecs) or you have to make sure your NLE creators have graciously purchased the license for these codecs for you so you can edit natively (i.e. without changing the file format). The problem is magnified when NLEs start developing their own “favorite” codecs for editing natively. Avid’s DNxHD files, for example, cannot be opened in Final Cut without downloading Avid’s codecs (and even then you can run into problems). Neither can FCP’s Apple ProRes files be opened in Avid without installing Apple’s codec.
This system of proprietary file structures created dozens of RAW file formats when RAW was introduced into still cameras. By remaining open source, CinemaDNG is designed to prevent such confusion in the film world, since it is free for any camera or software company to use, improve, and implement. There is hope that CinemaDNG might become a standard of sorts, creating greater interoperability among cameras, NLEs, and platforms.
Despite the rosy dawn of CinemaDNG as a standard, another reason the format has received so much attention is that many NLEs do not support it (FCP-X is a notable exception). Even Adobe, who created the file system and released it into the public domain, does not yet provide full support in Premiere Pro. This is mainly because of the low prevelance of cameras that shoot CinemaDNG. However, as this rapidly changes, the pressue is on for editors to find some way to adapt to the footage they are receiving.
In response to this lack of support, Digital Bolex is spearheading the creation of a new NLE designed specifically (although not exclusively) for CinemaDNG. The concept is so new it doesn’t even have a name yet, but its innovative design harkens back to the days of film processing which had a different room for each post-production process. The proposed software would also be divided into tabs called “rooms,” which would help editors focus on a logical workflow, while allowing assistants to work in other “rooms” simultaneously without overwriting the program file. This focus on cooperation and the fact that it was built specifically for CinemaDNG may cause it to become a major player in the editing world, revolutionizing how editing is currently performed.
Like all RAW files, CinemaDNG files are immense and require more storage space than lossy files. However, the real problem lies in the lack of native editing support (“native” means the NLE can open and play the file in real time without any intermediate file formats). When a file is not handled natively, the editor must spend time transcoding the footage into a format that is native, such as QuickTime for FCP or DNxHD for Avid. While these files are smaller than their parents, they nevertheless greatly increase the amount of storage (and money) needed for a single project.
When using transcoded files, you also add a lot of time onto your workflow. Transcoding is a long and processor-intensive process. For long projects, an editor can take days or weeks to convert all the footage into a usable form – a cumbersome, inefficient, and often frustrating process.
Once the movie is edited using the transcoded files, an editor must then relink to the original files to reap the benefit of the RAW footage that was too large to edit with, but too excellent not to use. This process can be another time-consuming process, and some editors opt to send their projects to post-production houses to avoid the complications that can sometimes arise, making it an expensive step as well. This is a current drawback of CinemaDNG that will only be resolved with native support, a proxy system (like RED currently uses) and/or an improved system of relinking.
5. It’s Affordable
Perhaps the greatest allure and the best indication that CinemaDNG will grow into an industry standard is the fact that it’s been chosen as the recording format for two of the most affordable ultra-high definition cameras on the market – the Blackmagic Cinema Camera and the Digital Bolex. With both of these options only around the $3K mark (compared with RED’s Scarlet-X, which starts at almost $8K for the brain only), these cameras are almost guaranteed to become popular tools for the indie filmmaker.
This, in a nutshell, is CinemaDNG — an up-and-coming format that has all the earmarks of a revolutionary new file structure, but which is still in the early stages of its life cycle. Like all things new, it will take time before it’s able to change the editing landscape, but it has a good start. Regardless of whether it becomes entrenched in the professional market, the popularity of the Blackmagic Cinema Camera and the Digital Bolex is sure to bring it to the forefront of many conversations in upcoming months. So if you don’t already have a plan for handling CinemaDNG, now would be a good time to start considering your options. In the meantime, keep a watch on its progress – you never know when you might be the one looking at it in post.