ANR Light Wrap

Overview

Light Wrap takes the light of the background right behind an element and adds it to the element's edges, fading inward. A bright sky behind a head lights its rim; a dark wall adds almost nothing. It is the classic integration step for keyed actors and CG over a plate, the job you would otherwise do with Nuke's LightWrap.

The light lands only inside the element, and its alpha is never changed. Inward Width sets how far into the element the light reaches, in pixels, and Falloff how it fades; Background Softness sets, separately, how blurred the background light is. Highlight Protection holds the wrap back on edges that are already bright, and Lighting Blend chooses a gentle Screen or a brighter, linear Add.

Inputs

1. Foregroundrequired

   The keyed or CG element, premultiplied and placed where it sits over the plate. The light is added inside its alpha.

2. Backgroundrequired

   The plate or comp behind the element, aligned with it. Its light, blurred by Background Softness, is what wraps onto the edges. Without it the Foreground passes through unchanged.

3. Maskoptional

   Limits where the wrap is added, by its alpha.

Output. The Foreground with the wrap added and its alpha unchanged, ready for your Merge. View can also show it over the Background (Composite), the added light alone (Wrap Only) or where the light lands (Edge Matte).

Quick start

1. Add ANR Light Wrap to the element just before its Merge over the plate.
2. Connect the element to Foreground and the plate to Background. Leave View on Foreground and keep your Merge.
3. Set View to Edge Matte to see where the light lands, and set Inward Width for how far it reaches into the element.
4. Back on Foreground, raise Light Intensity until the edges pick up the plate's light. Use Falloff to keep the light tight to the edge or let it fade further in.
5. Set Background Softness: low values carry the background's detail onto the edge, high values only its overall colour.
6. If bright edges start to clip, raise Highlight Protection. Switch Mix between 0 and 1 to judge the effect.

The panel

The node's panel as Nuke shows it, with the values of a new node. Click any control to see what it does; tabs and sections work as in Nuke.

All controls

Tips

• Use Screen for a natural, gentle wrap and Add for hot backlight such as sun, fire or a bright window behind the element.
• Wrap Only gives the added light by itself, to grade it or add it back with a plus Merge.
• Give Background the plate as the viewer sees it behind the element, with its defocus and grade, so the wrap matches it.
• Order in the comp: key, ANR Despill, ANR Edge Color, Light Wrap, then the Merge. Edge Color fixes the colour the edge already has; Light Wrap adds light on top.

Good to know

• View: Composite already contains the Background. Don't merge it over the background again; use Foreground for your own Merge.
• The light is taken only where the Background has alpha. If the wrap is missing in places, check that the Background's alpha is solid there.
• Runs on the CPU: no GPU and no AI model needed.

Works with

ANR Edge ColorGives the soft edges of a keyed or rotoed element the colour of the background behind them, so they blend in, without touching the alpha.ANR DespillRemoves green or blue screen spill from a keyed element and brings back the brightness the spill took with it.ANR Light MatchKeeps a comped element's light in step with the plate: when the wall behind it brightens, darkens or flickers, the element changes the same way.ANR Black MatchMoves a comped element's blacks onto the plate's, and keeps them there when the plate's blacks drift with exposure, flicker or haze.