RAW and Log profiles are two different formats used in filmmaking to capture videos. Other commonly used formats include H.264 and H.265. The key difference lies in their ability to preserve a wide range of information, particularly the dynamic range.
To help you understand the concept of dynamic range and its significance in filmmaking, I have created a detailed video explanation.
When we press record, light hits the camera sensor, and several kinds of information are captured, such as color, exposure, and dynamic range. RAW files capture all that unprocessed and uncompressed data directly from the camera’s sensor. After capturing the data, RAW files are converted into a viewable format. External software such as Adobe Camera Raw, DaVinci Resolve, or Premiere Pro is commonly used for this purpose. It is recommended to use video formats like ProRes or DNxHD for efficient editing, and high-quality results as they are visually lossless and their compression differs from the high compression used in formats like MP4 and H.264. During the conversion process, you can adjust parameters such as exposure, color, white balance, and contrast.
On the other hand, in log profiles, when light hits the sensor and the image is captured, a gamma curve is applied to the image. It compresses the dynamic range by reducing the brightness of the brightest parts and lifting the brightness of the darkest parts while redistributing the tonal information by creating more variations of grays and whites to represent dark and light areas of the image. This compression helps retain more information in the shadows and highlights, which is why images captured in log profiles appear flat. Log files are in-camera processed and can therefore be directly imported and adjusted in popular editing programs.
Different camera models support different RAW formats. For example:
1. Canon:
- Cinema RAW (CinemaDNG)
- Cinema RAW Light
2. Sony:
- Sony RAW (X-OCN, XAVC RAW)
- Sony RAW (ARW) – for still images
3. RED Digital Cinema:
- REDCODE RAW
4. ARRI:
- ARRIRAW
5. Blackmagic Design:
- Blackmagic RAW (BRAW)
6. Panasonic:
- V-Log RAW
Log profiles offered by different manufacturers
1. Sony S-Log: S-Log2 and S-Log3. S-Log2 is the older log profile introduced by Sony, while S-Log3 is a newer addition.
2. Canon C-Log: Canon’s log profile used in their cinema cameras. Canon Log is an older version used in some of their earlier models.
3. Panasonic V-Log
4. ARRI Log C
5. REDLogFilm
Shooting in RAW has the advantage of capturing raw, uncompressed data without any adjustments like white balance, exposure, or ISO. It represents the scene exactly as the sensor sees it, untouched. However, it’s important to note that RAW is a non video format, that is why the data cannot be viewed on a monitor while shooting, which is a drawback. Furthermore, because it is uncompressed, the files are large.
In contrast, shooting in the LOG format provides footage with a flat look and ample information, although it is still a compressed video format with certain elements pre-applied. The benefit of shooting in LOG is the immediate visibility on the monitor and smaller file sizes, making it a more convenient option for day-to-day productions, especially for projects intended for online streaming platforms like YouTube or OTT.
Shooting in RAW provides greater flexibility and control over the image, but it is a time-consuming process. Storage is also a significant concern, requiring substantial investment in storage units capable of handling the massive data size. Building a dedicated post-production unit for RAW processing, including a powerful GPU and suitable computer specifications, is necessary.
The advantage of the LOG video format is that it allows for easier editing without the need for conversion. The post-production process typically involves two steps: color correction and color grading, as LOG footage appears flat.
The compression applied to RAW files aims to reduce the file size for editing and storage purposes while retaining the original data. On the other hand, in-camera compression for LOG files aims to reduce file size while preserving a usable and editable video format, although it involves some degree of lossy compression.