Log footage is video recorded through a logarithmic transfer curve instead of a display curve, so the camera spends its available code values on capturing dynamic range rather than on looking finished. It arrives flat and desaturated by design, and it is meant to be normalised and graded before anyone sees it.
That one sentence settles most of the confusion, but not the practical part: which curve your camera shot, where middle grey is supposed to land, and what order to do things in so the grade holds up. This guide covers all of it, and links to the per-format walkthroughs where the details differ.
Why cameras record log at all
A sensor sees far more range between the darkest and brightest thing in a scene than a standard delivery format can carry. Something has to decide which parts of that range get precision and which get thrown away. A Rec.709 display curve makes that decision for you, at capture time, permanently: it bakes in contrast and saturation suited to a screen, and whatever fell off either end is gone.
A log curve makes the opposite decision. Because the curve is logarithmic, each photographic stop of scene light gets roughly the same number of code values, instead of highlights being squeezed into a handful of codes the way a display curve squeezes them. The image looks wrong on a monitor precisely because it is not for a monitor — it is a container.
Wikipedia's definition of the format family puts it plainly: a log profile is "a shooting profile, or gamma curve, found on some digital video cameras that gives a wide dynamic and tonal range, allowing more latitude to apply color and style choices", and "the resulting image appears washed out, requiring color grading in post-production, but retains shadow and highlight detail that would otherwise be lost if a regular linear profile had been used" (Wikipedia, "Log profile", read 12 September 2026). Apple says the same thing about its own capture: "Log footage is captured using a logarithmic curve to preserve a greater dynamic range than standard video, resulting in a flat, desaturated image intended for color grading" (Apple, Final Cut Camera User Guide, read 12 September 2026).
Every manufacturer publishes the formula for its own curve, which means the allocation is not a matter of opinion. We implemented nine of those published formulas and evaluated them directly; the result is our log format reference, and the figures in this article come from it.
How log looks, and why that is not "wrong"
Straight out of the camera, log footage has low contrast, milky blacks, no punch in the highlights and color that looks drained. People reach for the saturation slider, decide the camera is broken, or conclude that log "only works on expensive cameras". None of those is the problem.
Videomaker's guide to shooting log makes the point in the same terms: "The low-contrast image with washed-out colors is how your camera captures more dynamic range in your video files," and the same piece is blunt that "you need to color correct and color grade your video before you finish it" (Videomaker, "The dos and don'ts of shooting in log", read 12 September 2026).
If your specific complaint is that the picture looks grey and lifeless on a Sony body, the diagnosis and the fix are in why S-Log3 footage looks washed out.
Log vs Rec.709 vs RAW
These three get used as if they were points on one scale. They are not: two of them are recording formats and one of them is a delivery standard.
Rec.709 is the broadcast HD standard your delivery is almost certainly graded into. A camera shooting a Rec.709 picture profile is applying a display-referred curve at capture, producing footage that looks correct immediately and grades badly, because the decisions are already baked in. For a quick-turnaround job with no grading stage, that is a legitimate choice, and Videomaker says so.
Log is still ordinary encoded video — same codec, same file sizes, same debayering already done. What differs is the transfer curve. You can play it, scrub it, and cut it on any machine that handles the codec. It needs a color-managed transform or an input LUT before it looks like anything.
RAW is sensor data, not a picture. Debayering, white balance and exposure interpretation all still lie ahead of you, which is why RAW gives you more latitude and much larger files. Apple's own comparison says RAW "retains all the image information from the camera sensor for maximum flexibility in post-production" while log "requires color grading and offers less post-production flexibility than RAW" (Apple, Final Cut Camera User Guide, read 12 September 2026).
The practical summary: camera log is the middle option. Most of RAW's grading latitude, none of RAW's file size or debayer requirement, and one extra step in post that you must not skip.
The per-format table
Every camera maker's log curve is a different curve. The table below gives, for each format, the 10-bit full-range code value that an 18% grey card and a 90% white card land on, plus the code value at zero reflectance and how many stops of headroom sit between middle grey and code 1023.
These figures are computed, not measured: each manufacturer's own published encoding formula is implemented in lib/log-curves.ts in the Leumos codebase and evaluated directly at 0.18 and 0.90 reflectance. Nothing here is read off footage, fitted to a LUT or reverse-engineered, and every implementation is checked against the anchor values its own manufacturer prints before the numbers are generated. The full dataset, including a code value at every stop from six under middle grey to six over, is published at /tools/log-reference under CC BY 4.0.
| Format | 18% grey (CV) | 90% white (CV) | Zero reflectance (CV) | Stops above grey to 1023 | Source formula |
|---|---|---|---|---|---|
| Sony S-Log3 | 420.0 | 597.9 | 95.0 | 7.74 | Sony S-Log3 technical summary |
| Panasonic V-Log | 433.0 | 601.7 | 127.9 | 8.00 | V-Log/V-Gamut Reference Manual |
| Canon Log 3 | 351.3 | 577.5 | 128.0 | 6.35 | Canon Log Gamma Curves white paper |
| ARRI LogC3 (EI 800) | 400.0 | 572.3 | 94.9 | 8.26 | ALEXA Log C Curve — Usage in VFX |
| ARRI LogC4 | 284.8 | 427.6 | 95.0 | 11.35 | ARRI LogC4 specification |
| RED Log3G10 | 341.0 | 494.5 | 93.7 | 10.00 | REDWideGamutRGB and Log3G10 white paper |
| Nikon N-Log | 372.0 | 603.2 | 127.2 | 6.36 | Nikon N-Log specification |
| Fujifilm F-Log | 469.9 | 705.4 | 95.0 | 5.34 | F-Log data sheet |
| Fujifilm F-Log2 | 400.0 | 569.9 | 95.0 | 8.34 | F-Log2 data sheet |
Computed 12 September 2026 from the formulas as transcribed in the Leumos codebase; the linked documents are the manufacturers' own, and Sony's and Canon's hosts refused our automated request that day, so those two rows link out rather than quoting new text.
Three things worth pulling out of that table.
Middle grey is not in the same place twice. F-Log puts an 18% card at code 470 and LogC4 puts it at 285. A LUT built for one curve applied to another is not "close enough"; it is a different curve.
Canon's axis is not reflectance. Canon's white paper normalises its input axis so that 100% is a 90% white card, which puts an 18% grey card at x = 0.20, not 0.18. Read the axis as reflectance and you get code 339 for middle grey instead of the correct 351.
Blackmagic is the odd one out on range. Blackmagic Film Generation 5 is the one common curve published against video levels rather than full range. Blackmagic's own mapping table prints 18% grey at code 400 and zero reflectance at code 145 — where the full-range curves put black at 95. Applying a full-range assumption to it moves black by fifty codes.
Apple Log is not in this table. Leumos supports Apple Log as an input transform, but Apple does not publish its curve in the same closed-form shape as the nine above, so we have no computed figures for it and will not invent any. Apple's own reference material is the place to start: see Apple ProRes and Apple Log, read 12 September 2026, and our Apple Log workflow on Windows guide for the practical path.
If you want the long version of how these curves spend their code values against each other, that is how log formats allocate code values.
Exposing log
Log does not make exposure forgiving; it moves where the safe zone is. Two rules cover most of it.
Know your camera's middle grey. The table above is the number that matters on set: on S-Log3, an 18% card reads code 420, which is 41.1% of the full-range scale and 40.6 IRE on a legal-range scope. Underexpose below that and you are grading noise back up out of the shadows; the log curve's toe has fewer code values down there than the picture suggests.
Expose to the right, but measure it. Most colorists rate log stock slower than the camera's marked ISO and expose one to two stops over, then bring it back in the grade, because that pushes the picture up onto the part of the curve with the most code values. How far you can push depends on your camera and your highlights, and it is a decision to make with a waveform rather than a rule of thumb. The specifics for Sony are in how to expose S-Log3 correctly, and the reason overexposure fixes grain is in noise when grading log footage.
Videomaker's advice on set holds across brands: use a preview LUT on the monitor so you are judging a normalised picture, keep recording the flat log file underneath, record 10-bit rather than 8-bit, and watch scopes rather than the viewfinder (Videomaker, read 12 September 2026).
Grading log: normalise, correct, then look
The order is the whole trick, and it is the same order in any application.
1. Normalise. Apply the input color transform — or input LUT, or camera-specific setting — that matches what you actually shot. Not a forum LUT, not "a LOG to 709 pack", the named transform for your format. Until this is done, nothing downstream is valid, because the software is interpreting your code values with the wrong curve. If you have ever wondered why a color space transform, an ACES pipeline and a LUT give three different pictures from the same clip, that is why CST, ACES and LUTs look different.
2. Correct. Fix exposure and white balance on the normalised image, on a waveform and a vectorscope rather than by eye. This is the unglamorous pass, and it is the one that decides whether anything after it works. Our waveform monitor guide and vectorscope guide cover reading both.
3. Look. Only now do you build contrast, color and any film emulation on top. A look applied before normalisation is a look built on an arbitrary curve, and it will not carry to the next clip.
The full seven-step version, tool-agnostic, is how to color grade video. If the distinction between steps 2 and 3 is the part that is fuzzy, read color correction vs color grading.
Common mistakes
Grading before normalising. The single most common one, and the cause of most "my log footage won't grade" posts.
Using a LUT meant for a different curve. Or for a different exposure index — ARRI publishes eleven LogC3 parameter sets from EI 160 to EI 1600, and the top of the curve genuinely moves between them.
Adding saturation to fix flatness before correcting. Saturation applied to an un-normalised log image amplifies whatever color cast is in the container, not the color in the scene.
Underexposing because "log holds shadows". It holds highlights. The shadows are where log has the least to give, and where the noise lives.
Mixing log and baked-in Rec.709 clips in one scene without a plan. Videomaker warns that mixing formats across cameras makes clips "more difficult to match" in the edit; if you are already in that position, matching log footage to baked-in LUT clips is the recovery path.
Assuming you need one specific application. You do not — see grading log footage without DaVinci Resolve.
Where Leumos fits
Leumos is our own product: a browser color grading studio. For log work, two things are relevant. It carries named input color transforms for the formats it supports — its own documentation lists "supported Sony S-Log3, Panasonic V-Log, Canon Log, ARRI LogC3/LogC4, Nikon N-Log, and Apple Log options" (leumos.ai/llms.txt, read 12 September 2026) — so step 1 above is a menu choice rather than a hunt for a LUT. And it matches one selected shot to a still-image reference, which you then review in motion and refine; reference matching runs on one selected shot at a time in this release. Built-in waveform and vectorscope displays cover step 2. Plans and limits are on the pricing section.
Guides by format
Per-camera walkthroughs, each with the exposure and normalisation specifics for that curve:
- How to grade C-Log3 footage — Canon
- How to grade F-Log footage — Fujifilm
- How to grade N-Log footage — Nikon
- How to grade V-Log footage — Panasonic
- How to expose S-Log3 correctly — Sony, on set
- Why S-Log3 footage looks washed out — Sony, first diagnosis
- S-Log3 to Rec.709 conversion — Sony, the transform itself
- How log formats allocate code values — the cross-format comparison
- Apple Log workflow on Windows
- Matching log footage to baked-in LUT clips
- Noise when grading log footage
- Grading log footage without DaVinci Resolve
- Why CST, ACES and LUTs look different
- Applying a LUT to log footage in Premiere
Wider context: AI color grading explained for what automation can and cannot do with this footage.
FAQ
What is log footage?
Log footage is video recorded through a logarithmic transfer curve rather than a display curve, so each stop of scene light gets roughly equal code values. It holds more dynamic range than a standard picture profile, looks flat and desaturated straight out of camera, and is intended to be normalised and graded in post.
Why does log footage look washed out?
Because it is not encoded for a display. The flat, desaturated picture is the container, not the image: contrast and saturation are deliberately left out so shadow and highlight detail survive. Applying the correct input transform for your camera's curve restores a normal-looking picture.
Should I shoot log?
Shoot log if the project has a grading stage and you want latitude. Skip it for fast turnarounds, social clips, or footage someone else will cut without grading — a Rec.709 profile is finished sooner and matches more easily. Log with no grading pass looks worse than not shooting log.
What is the difference between log and RAW?
Log is ordinary encoded video with a logarithmic curve; debayering and white balance are already applied. RAW is sensor data with those decisions still open, which gives more latitude and much larger files. Apple states RAW keeps "all the image information from the camera sensor", while log "offers less post-production flexibility than RAW".
Do I need a LUT for log footage?
You need a correct input transform, which a LUT is one way to supply. A color space transform or a camera-specific setting does the same job more precisely. What you should not use is a generic "log to 709" LUT built for a different camera's curve — middle grey lands in a different place on every format.
Can AI grade log footage?
AI tools can normalise, correct exposure and white balance, and transfer color from a reference onto log footage once it is interpreted correctly. They do not remove the normalisation step, and creative intent, mixed lighting and skin still need your judgement. See our guide to AI color grading.