How to Color Grade Sony S-Log3 Footage

S-Log3 is Sony's widest dynamic range log profile, available on the A7 IV, A7S III, A7C II, FX3, FX6, and most of Sony's cinema line. It captures up to 15 stops of dynamic range — significantly more than the 8–10 stops of a standard colour profile.

The trade-off is that raw S-Log3 footage looks completely washed out. Shadows are lifted, highlights are compressed, and the overall image looks grey and flat. This is correct — the information is all there, it just needs a technical correction before you can grade it.

Understanding S-Log3 and S-Gamut3.Cine

S-Log3 refers to the gamma curve (how the camera encodes light levels). S-Gamut3.Cine is the colour space — a wide-gamut colour space designed to capture more colour information than Rec709.

Most Sony cameras let you shoot S-Log3 with either S-Gamut3 or S-Gamut3.Cine. S-Gamut3.Cine is recommended for most use cases — it's easier to grade and has better compatibility with standard colour science tools.

When you apply a technical LUT, it needs to match both the gamma and the colour space you shot in.

Step 1 — Get the Official Sony Technical LUT

Sony publishes free technical LUTs for S-Log3 → Rec709 conversion:

• Go to Sony's professional LUT library
• Download the LUT for S-Log3 / S-Gamut3.Cine → Rec709
• The file will be named something like SLog3SGamut3Cine_To_LC-709.cube

This is your technical base. It converts the flat log footage to a normal-looking Rec709 image with accurate, neutral colour.

Step 2 — Extract a Frame from Your Footage

Luttie works on still images. Extract a representative frame from your S-Log3 clip:

• VLC: Pause on the frame → Video → Take Snapshot
• QuickTime: Pause → Edit → Copy → paste into Preview → export as PNG
• Premiere: Export a single frame from the timeline

Choose a frame with a good mix of light, shadow, and any important subjects (faces, sky, architecture).

Step 3 — Apply the Technical LUT

1. Open luttie.app/editor and upload your frame
2. In the Creative section, drag the Sony S-Log3 .cube file into the LUT drop zone
3. The image should now look neutral — correctly exposed with realistic colour

Check the result:

• Neutral areas (grey concrete, white walls) should have no colour cast
• Skin tones should look natural — not orange or green
• Sky should be clean blue
• Shadows should have detail, not be crushed

If the image still looks flat, make sure you're using the right LUT variant. Sony makes several — check you have the one matching your camera's colour space (S-Gamut3.Cine is the most common).

Step 4 — Build the Creative Grade

With the technical correction applied, you're grading a neutral image. S-Log3 after correction tends to be clean and accurate — Sony's colour science is reliable, so you're not fighting a colour cast.

Basic Correction

• Exposure is usually correct after the technical LUT, but adjust if needed
• Contrast: +10–15 to add punch back
• White balance: Camera WB is reliable in daylight. For mixed or indoor light, adjust here

Curves — define the look

• Master S-curve: pull shadows down slightly, lift midtones — adds contrast and depth
• Red channel: lift midtones for warmth, or pull down for cooler look
• Blue channel: pull midtones down for warm/orange look, or push up for cool/cinematic blue

Colour Wheels

• Shadows: push slightly teal or blue for the classic cinematic split
• Midtones: push slightly amber or orange
• Highlights: neutral or slightly warm

HSL

• Oranges: boost saturation +10 (skin tones and warm highlights)
• Blues: reduce saturation -10 (skies and backgrounds)

Step 5 — Export the LUT

Click Export LUT (.cube) at the bottom of the panel. The exported file contains the Sony S-Log3 correction and your creative grade baked together.

Apply it in your NLE:

• Premiere Pro: Lumetri Color → Creative → Look → Browse
• Final Cut Pro: Effects → Custom LUT
• DaVinci Resolve: Import into LUT browser, apply in Color page
• CapCut: Adjust → LUT → import

Sony-Specific Tips

Camera WB is reliable. Sony's auto white balance and camera white balance settings are accurate. In daylight conditions, trust the camera WB rather than manually adjusting in post — it saves time and usually looks better.

The A7S III and A1 have exceptional shadow detail. Don't be afraid to push shadows aggressively in the grade — these sensors handle shadow recovery well without introducing significant noise.

S-Cinetone is a gentler alternative to S-Log3. If you find S-Log3 correction difficult to get right consistently, Sony's S-Cinetone profile is a less-flat starting point that's easier to grade directly while still preserving more dynamic range than standard profiles.