hooting LOG vs. RAW is all about shooting better pixels. LOG and RAW is not the same thing. But when should you use them?
You don’t need to know the mathematics behind them to use them, just understand their purpose and choose what works best for your situation.
Here’s a brief summary of the differences.
LOG is regular video - you make and bake a decisions about what your footage should look like (like ISO, color balance, gamma) into the signal. It has it’s origins with motion picture from back when motion picture films was scanned with a Telecine. Since the scans didn’t have the look of film, companies like Kodak developed Cineon film scanning where they added a log curve to be able to bring out more “density” in the footage.
So you can do some things with it later on in post, but you’re committing to other decisions (this is one of the reason filters exists). LOG content is going to look flat, desaturated and with low contrast, but it allows you to preserve shadow and highlight detail.
Different manufactures since made their own flavor of LOG coupled with different color coding like DJI’s D-Log. Each manufacturer calculates the LOG curve with respect to their specific sensor for optimal quality. Some manufactures, like Blackmagic, uses less techical names like “Film mode”, but it’s all the same. LOG curves from the same manufacturer typically pairs back up so it’s easier in post to match shots from different cameras.
Shooting in LOG doesn’t lead to a significant larger file size. LOG isn’t a change to exposure when shooting, but it’s a change in how the camera maps the information your giving it, and it will keep data within a smaller range that makes it easier in post-production to manipulate for shadows and highlights.
LOG - regular video - definitely has it’s purpose. Shooting RAW fx. for a newscast or live sport event is probably not going to work. Also, file sizes will be smaller and hardware requirements are smaller.
RAW is a totally different beast and has it’s origins with Raw photography.
RAW is not video.
If you take the RAW signal itself, then it’s not something you can actually see. RAW is just data. RAW data recorded by your sensor.
By the time you see raw video it’s already been processed by what’s called a Bayer pattern (twice as many greens as red/blue).
This relates to how the human eye sees detail. You can see lots more shades of green than any other color. So when you can actually watch RAW it’s been “Debayered”. Debayering is incredible hard for computers to do. Just a few years ago it took super computers with dedicated PCI cards to do this. Debayering is kind of like “developing” the files.
The real advantage - and the whole reason for shooting RAW - is that it bypasses a lot of the in-camera processing that you find in a regular videocamera, where you’re committing to a set ISO, gamma, white balance etc. These parameters will be available as metadata for you to manipulate later in post. Got the wrong WB on set? No problem. Just change it in post.
RAW gives you a massive advantage and flexibility when you color correct and grade.RAW definitely has it’s purpose. Like in high-end productions, time lapses, product photography or shooting a scene under natural light with a wide dynamic range. The downside: MUCH bigger file sizes. And of course the ability for your computer to actually, you know, play and edit these gigantic files.I hope this post could help clear up a few things for some?
All feedback is appreciated.
Written by Tony Airflix at Airflix.dk