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Takumi Chiba
Takumi Chiba

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Making creative LUTs safer for Rec.709 video

A strong creative LUT can look great on the footage it was designed around.
That does not mean it should hit every source the same way.

This was the problem behind the latest Filmtone Desktop release.

Filmtone has built-in creative Looks named Stone, Urban, and Noir. They are
designed to do more than a tiny color nudge: they can move contrast, hue,
saturation, glow, softness, and the optical finish of the image.

That is useful when the source is ready for a creative transform.

It is less useful when the source has already been rendered for display.

The source is part of the color decision

Rec.709 footage is often already opinionated.

It may already have:

  • display contrast baked in;
  • saturation pushed into a consumer-friendly range;
  • highlights compressed into a smaller space;
  • skin and sky colors that are usable, but not very flexible.

If a full creative LUT is applied directly on top of that, the failure mode is
easy to recognize:

  • highlight color breaks;
  • skin shifts too far;
  • saturation feels harsh;
  • dark color separation collapses;
  • lowering the whole LUT intensity makes the result safer, but also makes the Look less useful.

The tempting fix is simple:

If the source is Rec.709, reduce LUT intensity.
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That helped, but it was not enough.

It made the transform less aggressive, but it did not change the shape of the
transform. The same hue and saturation moves were still there, just blended
back toward the source.

What changed in Filmtone Desktop 1.12

Filmtone Desktop 1.12 adds dedicated Rec.709-safe variants for the built-in
Stone, Urban, and Noir Looks.

On Rec.709, SDR BT.709, Display P3 SDR, or unknown display-referred sources,
the Desktop renderer now chooses a safer Look variant instead of only lowering
the full Look intensity.

The intent is not to make the result flat.

The intent is to keep the useful parts:

  • glow;
  • softness;
  • grain and finish controls;
  • before/after comparison;
  • playback review before export.

And pull back the parts that break fastest on already-rendered footage:

  • strong hue travel;
  • saturation spikes;
  • aggressive highlight color shifts;
  • compression moves that were tuned for a different source state.

Full Looks still matter

This does not mean every source should be treated like Rec.709.

If the footage is normalized through an explicit Log or camera profile path,
Filmtone keeps the full Creative Pack 01 Look behavior.

That distinction matters.

The product should not flatten all sources into one generic safe path. A Log
clip waiting for normalization is not the same starting point as an iPhone or
camera file that has already been rendered for display.

Filmtone now keeps those paths separate:

source profile / source state -> base grade -> optical finish -> creative Look decision -> export
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Preview and export must agree

The other important part is less visible, but more important for trust.

Preview, still export, video export, and video composition rendering all resolve
the same source-aware built-in Look variant.

That means if a Rec.709-safe preview is shown, the export path uses the same
decision.

For a finishing tool, that matters more than having a long feature list. The
basic promise is:

What you judge in playback should be the thing you export.
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Where this fits

Filmtone is not a full editing suite replacement.

It is a smaller tool for a smaller moment:

  1. Open a clip.
  2. Choose a Preset or Look.
  3. Compare while the footage moves.
  4. Adjust only what the footage asks for.
  5. Export on Mac when the result is ready.

The Rec.709-safe variants make that path more reliable for the kind of footage
people already have: phone clips, camera files, SDR exports, and footage that
is technically usable but not yet finished.

If you work with video and LUTs, I would like feedback on whether this split
matches how you think about source material.

Try Filmtone:

Product Hunt launch will follow after this article has collected some early
feedback.

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