Fridays for Fusion: Lens flares, node by node

For those who don’t know the tool: Blackmagic Fusion is the node-based compositing environment inside DaVinci Resolve and Fusion Studio. Millolab’s LFTools arrives through Reactor as a box of lens-flare building blocks, letting compositors assemble, track, mask and animate flares inside the same graph as the shot.

Flare, meet node graph

LFTools takes the most Fusion-like route possible to lens flares: instead of one enormous effect with an enormous Inspector, Emilio Sapia’s Millolab splits the flare into individual macros. There are separate elements for Glow, Star, Ring, Iris, Custom Iris, Hoop and Line, plus a central LF Controls macro. Add what the shot needs, ignore what it does not, and keep connecting nodes until the optics department starts asking questions.

LF Controls provides shared light and axis positioning, while individual elements retain their own appearance controls. The result is less “choose flare number 17” and more “build the peculiar little optical accident yourself.”

Irises behaving badly

The procedural Iris is one of the more interesting parts. It provides controls for polygon sides, rotation, stariness, colour and scale, then distributes multiple copies along the flare axis. Position, size, angle, colour and opacity can be jittered, with a random seed available when the current collection of circles looks suspiciously well organised.

Shared controls add treatments including aberration, diffraction and occlusion. Occlusion can progressively hide iris elements, while diffraction introduces directional blur. These are artist controls for constructing a flare look, not a documented physical lens simulation.

Bring your own blob

Custom Iris swaps the procedural source for an image arriving through the Fusion graph. In Sapia’s demonstration, a bitmap is converted to luminance and fed into the macro, after which it can use the same multi-iris behaviour. That is where the node-based design becomes genuinely useful. The source image can already have been graded, blurred, masked or otherwise bullied into shape upstream.

Hoops, stars and sparkles

The other elements are suitably tweakable. Glow separates main glow, secondary glow and sparkle. Star exposes size, angle, blur, thickness, colour and jitter. Ring provides its own thickness control. Hoop can automatically rotate and scale as the flare moves, or keep its rotation fixed while still scaling. Offset controls let it wander away from the centre, and spectral controls provide further chromatic mischief. Because these components remain separate nodes, a compositor can animate or suppress them independently rather than negotiating with a single master effect.

Tracking stays home

Sapia’s practical example tracks a light source in footage and uses that movement to drive the flare. A Probe modifier controls when the effect appears and disappears. That keeps tracking, animation, masking and flare construction inside Fusion. There is no separate flare application and no positional hand-off to maintain. The macros are also resolution independent, with the demonstration built at 1920 x 1080 while retaining the same flare behaviour when resolution changes.

The price of plumbing

LFTools is distributed as a free Reactor atom and declares Steve Watson’s LinearCloner Fuse as a dependency. The modular approach does have a price, although not necessarily one involving accounting. Sapia notes that interactive refresh slows as more flare elements are added and explicitly contrasts the macros with faster dedicated plug-ins.

Presets for the impatient

Millolab also sells an LFTools Preset pack, currently listed at $10. This is more a suppot for the developer, then a “accountable license”. The Gumroad item is the preset pack, not LFTools itself, and its page instructs users to install LFTools through Reactor.

So the choice is pleasantly traditional. Build your flare from scratch and spend twenty minutes adjusting an iris nobody will consciously notice, or start with a preset and spend twenty minutes adjusting it anyway.

https://millolab.gumroad.com/l/RMkNZo
https://kartaverse.github.io/Reactor-Docs/#/com.Millolab.ml_LFTools?id=lftools