Halation

Halation is the warm glow that wraps bright sources on film: the bloom around a practical, or the red edge on backlit hair. Reflected light favors the red layer, backing absorbs some of it, and a smaller gauge makes the halo larger relative to the frame. In Film/Emulsion™, use the Halation tab to set its strength, spread, and color. This tab renders the visible halo only. Image softness lives on the Grain tab, which you set independently.

Simple and Advanced

The Halation tab has two modes, set by the Mode menu.

Simple gives you two sliders, Amount and Character, that drive the complete halation engine underneath. Nothing is switched off in Simple mode. Under the hood, Amount and Character set all four Advanced controls and the backing together. Film Gauge is separate, and Simple mode hides it; switch to Advanced to change it.

Advanced exposes the model’s halation parameters: reflection strength, scatter distance, layer crosstalk, and irradiation, alongside the gauge and the backing.

Switching from Advanced back to Simple can change the halo. Simple derives Amount and Character from what you set and re-applies its own mapping, so a hand-set Crosstalk or Irradiation the two sliders cannot reach gets overwritten. Simple to Advanced never changes the image; it shows you the parameters that make the halo you already have.

Every Film Look preset sets this tab as part of its recipe, so a look arrives with the halation its stock would show before you touch a slider. If the tab is in Simple mode when a preset loads, Amount and Character move to show the recipe. Many presets sit outside what the two sliders can express, and for those the tab switches itself to Advanced rather than show you sliders that do not match the halo on screen.

Start in Simple. Move to Advanced when you want to pull one variable on its own.

Simple mode

Amount

Amount sets the strength of the reflection halo: how much of the returning light the model lets back into the image. It scales strength and nothing else, so the size of the halo stays where Character and the gauge put it. The brightness a source needs before it halates is set by the Quality mode, not by Amount. The midpoint is the default; below it every halo dims together, above it every halo gets brighter.

Character

Character describes what kind of halo you get. At the left end the halo is tight and red, hugging the source the way a remjet-backed modern stock behaves. Past the middle it warms toward orange and blooms at its core, like a stock that is not protecting itself. The right end is the largest and softest halo the model makes, a stock with no backing at all.

Amount and Character at their midpoints are the halation the plugin ships with when no preset is applied.

Advanced mode

Advanced mode replaces Amount and Character with four percentages. Reflection and Base Scatter work relative to the backing you pick, with the backing’s own value at 100%. Emulsion Crosstalk and Irradiation are direct amounts and do not depend on the backing.

Reflection

Reflection (%) is how much light reflects off the film base. The closest thing to a pure strength control: raise it and every halo gets brighter without changing the spread.

Base Scatter

Base Scatter (%) is how far sideways the returning light spreads before it re-enters the emulsion. It sets the size of the halo. Raise it for a wider, softer bloom. Lower it for a tight edge glow. Film Gauge then scales the result to the frame.

Emulsion Crosstalk

Emulsion Crosstalk (%) is how much of the returning light reaches the green layer. At zero the halo is at its reddest, with only a trace of warmth; pure red is not reachable, because a little green-layer exposure always survives. Raise it and more green bleeds in, warming the halo toward orange. This is the color control for the halo. There is no separate hue or RGB balance, because the color of real halation is decided by which layers the returning light reaches, and this slider stands in for that.

Irradiation

Irradiation (%) is a tight core bloom, separate from the base reflection. It stands in for light scattering sideways within the emulsion itself, before it reaches the base, and shows up as a bright core on the edges of hot sources rather than a wide halo. Keep it low: a few percent adds a hot edge to speculars, and the top of the range is for deliberate effect.

Film Gauge

Film Gauge sets the physical size of the frame, from 8mm to IMAX. Smaller gauge, bigger halo relative to the frame. Switching a 35mm look to Super 16 makes the halation larger without touching any other control; 65mm makes it much smaller.

Film Gauge is also on the Grain tab. The two are independent, so you can size the halation for one gauge and the grain for another if a look calls for it, but for a conventional matched-stock setup keep them the same.

Anti-Halation Backing

Anti-Halation Backing picks which of three backings the halo is built from, and sets the starting reflection and scatter that Reflection (%) and Base Scatter (%) then scale. Each is named for the real backing it stands in for.

• Modern Remjet. A carbon backing that absorbs most of the light before it can reflect. Tight, faint, red halo.
• Vintage Dye. A dye layer instead of carbon: absorbs less, scatters further. A larger, brighter halo. The plugin’s default.
• No Backing. The highest reflection and widest scatter the model offers, for the biggest, brightest halo it produces.

In Simple mode the Character slider chooses the backing for you. In Advanced mode you choose it here.

Opacity

Opacity blends the complete halation result against the image without it. It is a wet/dry control on the whole stage rather than a strength control on the halo: the halo is still shaped by Amount and Character, or by the Advanced parameters, and Opacity fades the finished result in or out. Use it when a look is right but there is too much of it. Use Amount when the halo itself needs to be weaker.

Controls

Working with halation

Judge it with grain on. A halo over a clean image reads as a glow filter, not as film, so keep the Grain stage enabled while you set halation, even at low opacity. Judge it on the right shots, too: a flat interior with no practicals tells you nothing. Find the shot with a window, a lamp, or backlit hair and set it there.

Reach for Amount before Opacity, because Amount changes how the film behaves while Opacity only fades the result. If the halo is too wide or too warm, Character or the Advanced parameters are the fix.

Set the gauge once, the same on Halation and Grain, and leave it. It is part of what makes a 16mm look read as 16mm.

What the Halation tab cannot do

There is no sharpness control here. Halation is not sharpening or softening; image resolution is modeled on the Grain tab and does not read the halation settings.

There is no hue or RGB balance for the halo. Classical base-backscatter halation, the round trip this model renders, is red or orange. Emulsion Crosstalk is the whole color range, with one exception: the black-and-white presets switch on a neutral halo, which is preset-only. Other scatter effects exist on some stocks, and the plugin does not model them.

Halation renders after the print stage, over the finished image. The plugin does not model the separate halation a print stock adds during printing.

Next: Grain covers film grain, the stock and gauge it is sized to, and Bind Image to Emulsion.