Getting RAW with a DSLR – Part 1
Josh Harmon
When I was first beginning in digital photography, shooting in RAW vastly changed how I not only approached a subject or scene but how I thought about image. The same thing happened last Spring when I had the opportunity to use a Black Magic Cinema Camera. It appears that RAW has an alluring and exciting effect on me.
As with still photography, shooting video in RAW opens up a whole new world of possibilities and control in regards to image fidelity, color, sharpness and grain. With RAW one has the ability to push a scene with lighting and not have to worry about clipped highlights and ugly noisy shadows (I will explain more on this). However these manifold possibilities brings with them many many questions and issues. Questions regarding workflows to get from camera to final render and issues such as storage space and computing power. Keeping these things in mind my hope for this post is to answer and resolve (pun intended) many of the common questions and issues for this workflow. I also hope to provide an easy(er) to follow guide on how to shoot RAW video on a Canon DSLR using MagicLantern.
Before you start you should ask yourself why you are planning to shoot in RAW. That is, does your project need to shot in this format? For this post I'll assume you're using a DSLR, and thus is the compressed HD DSLR video work for your needs? Shooting with RAW on a DSLR is not a guaranteed error free and easy process. Here are some things to consider before you start:
1. How much storage space do you have available?
2. How fast are your memory cards?
3. How fast is your computer? Can it run Davinci Resolve?
4. How protective are you of your camera?
1. A RAW project takes disk space, lots of it. My project last Spring, shot with a BMCC at 2.5k RAW, filled up ~1.5TB of space. That's for about ~2 hours of footage, each frame, CinemaDNG, was 5MB. With my 7D an average frame is about 1-2MB, at a resolution of 1728x724.
2. On this same note, RAW video is all the data that means much more data that needs to be moved from the sensor to your memory card. With DSLR's the main limitation in resolution and shooting times are how fast your memory card is. I use a 60MB/s 32GB SanDisk Extreme CF card, which allows me to shoot for ~30 seconds at 1728x724px. A 1000x card will allow for higher performance.
3. This next one is pretty obvious as well. You don't need to run Resolve but you do need a computer that has lots of memory to be able to wrangle a CinemaDNG sequence. I will be using Resolve Lite, which is free (https://www.blackmagicdesign.com/products/davinciresolve), and am running it on a Mid-2014 MacBook Pro with 16gb RAM and a NVIDIA GeForce 750M w/ 2GB.
4. Lastly, Magic Lantern is not warranteed by Canon and most likely will void your warranty so be aware of this before you use it. Check their website for more info, magiclantern.fm.
With those questions asked the first thing needed is to install Magic Lantern on your camera. For me this was very straightforward, I just downloaded the latest nightly build for my Canon 7D, unzipped the file, and drop the contents on the root directory of my CF card. Then I popped the card into the camera, navigated to the firmware update function in the menu, and updated the firmware to accept Magic Lantern. A quick restart later and Magic Lantern is installed.
At this point I would recommend playing around with the different features the "Hacked" firmware adds. For shooting video my most used features are Zebra's, Focus Peaking, and Cinemascope cropmarks. Further, if you aren't shooting RAW then playing with the bitrate control can give you a little bit more quality with compressed video.
To get prepped to actually shoot RAW you actually have to load several modules first. Since I am using a 7D I will be specific for what works with it. In the Magic Lantern go over to the MODULES tab and load file_man, mlv_play, and raw_rec (NOT mlv_rec as I found this module doesn't work on my 7D). Then restart your camera, you are now all set to shoot RAW!
Now go to the VIDEO tab and and enable RAW video and then toggle the advanced option. From this menu you can set the resolution you want. I shoot almost all my projects at around 2.35:1 so I opted to have the aspect ration at 2.39:1. With my CF card the highest horizontal resolution I can get at that ratio is 1728x724. With a faster card I could push that a bit more. I also then turn on Show Buffer Graph, this is helpful for monitoring how full the video buffer is to know how many more frames you can film before the recording stops.
NOTE, Magic Lantern uses the framerate set in the regular Canon menus, so make sure you have that set to the framerate you plan to use. For me I almost always shoot at 30p and then conform to 24p so that my footage has a little bit of a overcranked look.
Now to shoot RAW video just go to movie LiveView and press the REC button. Information related to how many expected frames, the buffer monitors, and other misc information will appear. Also, as another note, the smaller the resolution the smaller the shooting area. Basically, if you select a small resolution, such as 1200x600 or something like that, you are actually only recording a smaller centered portion of the image. As if you record at a higher resolution, like I am, you get almost or the full complete view.
Once you have recorded some RAW video you can play it back by going to the raw_rec module. It loads the mlv_play module which allows you to playback (either slowly in color, or faster in B/W) clips you've shot. You can also delete clips from here too. The raw_rec records your clips as .RAW files. In the following post I will go over how to access these and get CinemaDNG files that you can work with.
So that is it for this first post! Hopefully this should shed some light on the process of RAW video. In the following post I will go over how to take your .RAW files and export CinemaDNG files which I will then incorporate into a Davinci Resolve and Final Cut Pro X workflow. Stay tuned!