Why RAW and LOG Recording Are So Important
This post is a series of notes I made during one of my NAB sessions back in April. This particular class, taught by Robbie Carmen, centered on both RAW and LOG recording; the definitions of each, the differences between the two, reasons why you should shoot in either format, things to consider when shooting RAW or LOG, production and post-production workflows, and some general guildelines.
Regular Video
Parameters are baked into the signal (white balance, exposure, color space, codec, etc.)
Easy to use
Limiting for maximum flexibility in postproduction
Why Should You Care?
You want the best looking image possible
It's all about capturing a ton of information and giving you the most flexibility in post
Capturing the most dynamic range
What RAW Recording Gives You
You can avoid sensor processing
Ability to change any exposure/color parameters on the fly
Avoid the pitfalls of regular video
Workflow Thoughts
Shooting RAW and LOG can complicate on set workflow
There's a need to normalize content for on set viewing (Remember that RAW and LOG will look extremely flat coming directly off the camera, which can confuse clients who are unfamiliar with the format.)
Potentially the need for additional on set personnel
Potentially the need for capable monitoring equipment
High capacity, fast storage is needed
DIT
A DIT manages data and workflow while on set.
Develops LUTs (Look Up Tables) and uses them
Potentially implements hardware
Potentially color corrects and grades while on set
The Onset Colorist
Grades from camera transfers on set
Grades live from the camera feed
First line of defense in processing footage - a) grades that can transfer to post, b) creates an initial look setting
Onset Viewing
Proper monitoring for LOG footage is essential
Many monitors are capable of supporting LUTs directly
RAW and LOG Are Not The Same
Logarithmic recording is a way of capturing an extended dynamic range in a scene
Multiple LOG curves exist for different manufacturers
Gamma is converted in post-production
RAW recording bypasses the sensor processing decisions, so nothing is baked in
RAW
RAW is not video. It's information; data
Color is produced on most cameras by filtering each pixel to produce RGB
The pattern of this filtering is called a Bayer Pattern which most cameras use
RAW data is in this array
Patterns differ, depending on the camera
All footage must be debayered in order to view it.
Not all RAW is created equal
RAW data is often compressed, some cameras more than others
Bit depths can range from 12-16 bits depending on the camera
16 bit RAW is not the same fidelity as 16 bit LOG
RAW bit depth does not apply well to the way we view images
While processing RAW you can often place it into the color space of your choosing and assign a gamma curve
Develop RAW to a starting point where you have the greatest flexibility in grading. Don't use RAW control as a principle form of grading.
LOG
LOG is processed footage
LOG is a particular type of Gamma curve
Manufacturers have their own flavor of LOG
Don't confuse "flat" with LOG
Shooting with reduced contrast, saturation and sharpness can help but it's not LOG recording
Many cameras try to approximate LOG recording
LUTs
LUTs have been the source of a lot of confusion
It transforms data into a specific color space
Technical LUT - the LUT you would put on a monitor
Creative LUT - a look or grade that a colorist can save and then be applied to any footage
Output LUT - profile a film stock, place it into your system so your grade matches the film stock you will output to.
You don't have to go to a LUT right away when bringing in the footage to your NLE. Just simply grade it when you drop it in. You don't have to drop a LUT on it. First, adjust the curves with a waveform monitor and then bump up the master saturation.
If you have anything to add from your experiences in shooting either LOG or RAW, feel free to leave your thoughts in the Comments section.