Videography FAQ: What is Canon Log?
You might have heard the term “shoot in log”. Read on to find out what this refers to, and about the different Canon Log modes found on most EOS R series mirrorless cameras.
Log: An encoding method that captures a wider dynamic range
Log: An encoding method that captures a wider dynamic range
Log recording is an encoding mode that enables a digital camera to capture a wider dynamic range (range of tones from shadows to highlights), so that more details in highlights and shadows can be retained. It is considered a “gamma”: a function that corrects the difference between how a camera records a digital image and what the human eyes perceive.
The following are screenshots from standard Rec.709 and Canon Log 3 footage. What do you notice? (All versions of Canon Log result in the same overall differences when compared to standard footage.)
The sun and surrounding cloud looks blown out in the Rec.709 recording, whereas Log recording preserves more highlight details. Log footage looks flatter out of the camera and must be colour graded to put the colours and contrast back in—but that’s also where the ample tonal information captured helps.
How does log recording work?
Recap: How digital images are recorded
During digital video recording, light entering the image pixels generates analogue signals, which are then converted into digital signals for recording. Conversion involves assigning a numerical value to the luminance information in each pixel. A gamma defines the relationship between the actual light intensity (tones) and the numerical value that the camera records.
Why we need gammas: Camera “perception” vs. human perception
Cameras “see” light differently from humans. Standard recording modes (such as Rec.709) record light the way the camera sees it: in absolute, linear terms. For example, if part of the scene has twice the light intensity as another part, the camera will record a value that indicates that it is twice as bright.
However, human eyes are not as sensitive to differences in brightness, especially in highlight areas. At a certain point, we cannot notice any difference at all—everything looks equally bright and blown out. Every bit of light information is data that takes up space, and it would be inefficient to store light information when we cannot perceive the difference.
Gammas, or gamma correction methods, were invented to encode information more efficiently in a non-linear manner: they preserve information in the tonal ranges that our eyes can perceive, and less information in the areas that we can’t. Different gammas work differently. The log gamma was first invented to simulate the way film negatives capture light. It is known as "log" as it encodes along a logarithmic scale instead of a linear one. The resulting footage contains more information on tone variations that are visible to us, which is also why they appear to have less contrast straight out of the camera.
Canon Log expands possibilities in these scenes
- High-contrast scenes
- Bright scenes where highlight details are important (e.g. wedding dresses outdoors)
- Productions that require colour grading
As Canon Log recording preserves more tonal information than standard recording, it is ideal for high-contrast scenes where you want to retain both shadow and highlight details. Examples include scenery against the sunrise or sunset, or scenes shot from indoors that show a location’s interior as well as the scenery outdoors.
Canon Log works exceptionally well with preserving highlight details, so you can use it in brighter scenes too. One good example is in outdoor weddings, where it can preserve elaborate wedding dress details that would otherwise become blown out.
The amount of information preserved also provides more leeway for colour grading in post-production: the footage remains high-quality even if you go more extreme.
While Log footage appears relatively flat out of the camera, it retains more details in highlights and shadows—notice the higher visibility of the sky details around the sun in the screenshots from the Canon Log 3 footage. This helps tonal transitions remain smooth even when the footage is graded.
Did you know: Canon Log helps digital video cameras achieve the traditional “cinematic” aesthetic
Cinematic film negatives record a wide 12-stop dynamic, which helps achieve colours that look deeper and with greater dimensionality. Digital video cameras, which were made to record for television, capture vibrant, high-contrast footage but with a more limited dynamic range. While such footage has its own appeal, the different visual aesthetics can be challenging to reconcile when post-producing mixed productions where both cinema film and digital video cameras are used. Log recording bridges the divide by replicating how film negatives capture light.
The first camera to feature Canon Log was the EOS C300—Canon’s first digital cinema camera released in 2012. Cinema EOS cameras are all Canon Log enabled, but many recent intermediate and advanced EOS R system mirrorless cameras are now also equipped with at least one Canon Log mode.
What’s the difference between Canon Log, Log 2, and Log 3?
What’s the difference between Canon Log, Canon Log 2, and Canon Log 3?
There are three different Canon Log modes: the original Canon Log, Canon Log 2, and Canon Log 3. The key differences between them are as follows:
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| Dynamic range | approx.12 stops 800% |
| Distinctive feature | Easier colour grading as image quality is close to Rec.709 (ITU-R BT.709). |
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| Dynamic range | approx.15 stops 1600% |
| Distinctive feature | Has characteristics close to film. Preserves more details in medium to dark areas. |
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| Dynamic range | approx.13.3 stops 1600% |
| Distinctive feature | Retains the advantages of Canon Log, but with greater dynamic range especially in the highlight areas. |
Canon Log 3
Most recent Cinema EOS and intermediate and advanced EOS R system cameras are equipped with at least Canon Log 3. It is an improved version of the original Canon Log, and retains highlight details better than the latter. Like the original Canon Log, it provides image quality very similar to Rec.709. As with all log videos, the out-of-camera footage is relatively desaturated, but minimal colour grading is required to add the colours back in. It’s the easiest type of Log footage to grade, and is suitable for productions that require a more streamlined post-production flow.
Canon Log 2
Canon Log 2 achieves a wider dynamic range than Canon Log 3: approximately 15 stops equivalent. It is better at preserving midtone and shadow details than Canon Log 3, in addition to highlight details. However, as a result of this, out-of-camera Canon Log 2 footage has less colour and contrast than Log 3 footage, making it more challenging to colour grade. It is better suited for larger productions, where heavy colour grading in post-production is required.
Crop of shadow areas
In the close-up crops, details in the shadow areas, such as the trees surrounding the houses, are more distinct in the Canon Log 2 footage than the Log 3 footage.
A tool for creating impressive visuals
The wide dynamic range offered by Canon Log shooting makes it possible to create HDR (high dynamic range) productions. After all, HDR refers to visuals that have a dynamic range so wide that they resemble the dynamic range perceivable to the human eye, and so appear truer to life. HDR in the form of high-resolution 4K or 8K footage enhances the true-to-life effect. Furthermore, Canon Log videos are always recorded at a 10-bit colour depth, providing ample colour information that further helps with colour grading. By harnessing the wide dynamic range that appears so realistic to human eyes, and applying colour grading to set the mood, you can create productions with astounding visuals.
Learn more about technical terms related to videography and what they mean in:
What are 8K, 4K, and Full HD? How Do I Use Them?
What do 4:2:2 and 4:2:0 mean?
What is Focus Breathing Correction?
