Halation

Halation reproduces a film-like light reflection: a fine red-orange halo appears around high-contrast lamps, windows and reflections. It stylizes an existing image; it cannot restore clipped highlights or turn every clip into a specific film stock.

Isolation determines which regions generate the halo. Threshold is the low clipping level and Normalization the high clipping level. Film Saturation Level sets the level above which bright color becomes white, which is especially useful in HDR. It is not a sensitivity control for saturated signs.

Use View Isolated Regions to tune isolation. In a shot containing a window and a face, separate the intended bright regions from skin and then inspect frames with different exposure. Changing Normalization is not automatic exposure stabilization over time.

Dye Layer Reflections shapes the main halo. Strength changes brightness, Spread changes extent, Gamma changes its distribution, and Saturation changes color intensity. Fine Tune Relative Spread exposes separate red, green and blue reflection distances; these are spatial controls rather than RGB gain.

Secondary Glow adds another layer with its own brightness, distribution and color filter. Evaluate the primary halo with Secondary Strength at 0, then introduce the second layer. Increasing both blocks together makes an excessively broad wash harder to diagnose.

Processing Color Space must match the actual working context of the effect. Use timeline follows the timeline color space; a manual choice should fit the established color pipeline. Choosing a familiar camera name cannot repair an accidental second CST or an incorrect input transform.

Basic Grain adds simplified grain to the halation layer and is enabled separately with Append Grain Internally. For broader control over the final film texture, use FilmGrain after Halation; leaving internal grain off avoids unintentionally stacking two textures.

Reduce Highlights reduces the effect inside bright regions where it adds brightness without contributing to the halo. Detail Loss softens underlying image detail. Aspect Ratio stretches or squeezes the glow and grain horizontally; it does not change clip resolution.

For a local treatment, keep an original branch and merge the processed copy through a mask on Merge.EffectMask. Leave room for the full halo: a tight boundary clips the glow. This separates source selection inside Halation from spatial blending of the completed result.

Judge the look at the final frame size and during playback. Compare the source, glow-only view and composite; inspect skin, neutral surfaces and adjacent frames with changing reflections. Disable both diagnostic views before output.