Pulsar Glow

Presets stamps one of 14 factory looks onto the dials that define the star — the lengths, the gate, Boost, both color ramps, and the routing between them. It leaves Star Rotation, Map Spin, Quality, Glow Only, and the Master dials exactly where you left them, so you can audition every look without losing your rotation or your compositing setup. The popup reads Custom the moment you touch anything.

Threshold decides which pixels flare, reading the average of the three channels. The dial is in display code with 256 as reference white: at the default Threshold = 160 a mid-bright wall still contributes, Threshold = 220 narrows it to specular hits, and past reference white only super-white values — blown practicals, HDR plates, 32-bit comps — survive at all. Going the other way, Threshold = 120 is the everything-glitters setting. Threshold Soft widens that cutoff into a ramp so pixels near the gate contribute partially. It’s the anti-sizzle dial: a hard gate makes highlights snap in and out between frames on moving footage, and Threshold Soft 15–30 fixes it. The default of 10 is deliberately tight.

Streak Length is the falloff constant in pixels — the distance over which a ray decays to roughly a third of its brightness, which is why the visible ray runs several times longer than the number you type. Streak Length 15–60 is jewelry and glamour work at 1080p; 100 and up turns every surviving highlight into a full burst; the default of 20 is a tight glint. Because each ray carries constant energy, a longer streak is a fainter streak per pixel, and that’s what Boost exists to put back. Boost is an exponential gain — each +25 multiplies the streak’s brightness by about 4.5×, so Boost 0–15 covers most shots, Boost = 40 is a deliberate blowout, and the default of 0 means the streaks arrive at their natural, unamplified level.

Glow Only drops the source image and outputs the star alone — the compositing route: put the pass on its own layer, then blend, grade, or offset it independently. With it off, the rays are simply added on top of the source.

Quality picks how each ray is sampled, Q1 through Q4, cheapest to most expensive. The falloff law is identical at every step — this is not a “more correct” dial, it’s a sampling-density dial. Short streaks look the same at Q1 as at Q4. Long ones sample in coarser steps at the low settings, which can show as stepping down the tail, so reach for Q3 or Q4 on finals with long rays. Q2 is the default and the right setting for previewing a heavy comp.

The star is eight fixed rays and ten dials that scale them. Four cardinals — Length R, Length L, Length U, Length D — and four diagonals — Length UR, Length DL, Length DR, Length UL. Each is a percent multiplier on Streak Length for its own arm, with 100 neutral. Above them sit two group dials: Cardinal Length scales all four cardinals together, Diagonal Length all four diagonals.

Zero is a hard off, not a short ray: an arm whose multipliers reach 0 is dropped from the render rather than drawn short, so switching arms off buys back time as well as changing the shape. That’s the fast route to the two classic silhouettes — Diagonal Length = 0 leaves a four-point cross (Pulsar, Neon Grid, Cryostream, Anamorphic Rig all start there), Cardinal Length = 0 leaves an X (Singularity, Forge Spark).

Between those extremes you’re deciding how much the cross leads. Both group dials at 100 is the even eight-point star, where four of the factory looks sit — Dark Matter, Event Horizon, Ember Drift, Ghost Light — and it’s the most graphic, most symmetrical read available. Pull Diagonal Length down to 45–60 and the cardinals take the lead while the diagonals fill the gaps between them; that’s the band Furnace, Glacier, and Solar Crown use, and it’s usually the more photographic of the two. Below about 30 they’re short enough to stop reading as arms at all — they just thicken the light at the source, which is a way to fatten a cross without lengthening it.

The per-arm dials are where the shape stops looking synthetic. A horizontal lens streak is Length R and Length L pushed way out while Length U and Length D are clipped to a stub — that’s Anamorphic Rig. A rising column of ice is Length R = 0, Length L = 0, Length U = 220, Length D = 180, which is Cryostream. Run one diagonal pair long and the other short — Length UR and Length DR at 200 against Length UL and Length DL at 40 — and you get the wind-blown star of Starfall. Asymmetry reads as direction; a perfectly even star reads as a graphic.

Star Rotation turns all eight arms together, in degrees, positive clockwise on screen. Multiples of 90 are the one exact case: the rotated arms land back on the same pixel grid the unrotated star used, a straight permutation of the eight directions with no resampling. Every other angle is interpolated, which costs nothing visible but is worth knowing when you compare a rotated render against an unrotated one. Star Rotation = 45 is the useful non-exact angle — it puts the cardinal arms where the diagonals were, so a cross reads as an X without touching a length dial. Star Rotation = 22.5 offsets an eight-point star from the frame axes, the fix when horizontal and vertical rays line up with architecture and start reading as artifacts. The colors travel with the arms when you rotate — if you want the colors to move and the geometry to stay put, that’s Map Spin.

Every ray is colored by a three-stop ramp read off its own brightness. Ramp A is A Shadows, A Midtones, A Highlights; ramp B is B Shadows, B Midtones, B Highlights. The hot end of a streak — right at the source — lands on A Highlights, the body runs through A Midtones, and the faint tail falls to A Shadows. The mapping is gamma-shaped, so A Midtones covers most of what you actually see: that is the stop carrying the look, and it’s the one to change first. A Highlights shows only in the hottest cores, which is why nearly every factory ramp keeps it at or near white — it’s the middle of a flare is too bright to have a color stop. A Shadows sets the tail’s darkest tint and is what keeps a long streak from dying gray. The factory defaults are the house pair: A green up to white, B red through orange to white.

Colormap Routing decides which arm gets which ramp. AE Default splits the star across both: Length R, Length U, Length UL, and Length DR take ramp A, and Length L, Length D, Length UR, and Length DL take ramp B. The split is deliberately not a clean alternation: neither half is a symmetric figure on its own, which is what keeps a two-ramp star from reading as a checkerboard. All A and All B collapse the whole figure onto a single ramp, which is what every monochrome factory look does. Set both ramps identically and routing stops mattering at all.

Map Spin rotates the ramp assignment around the star while the arms hold still, in degrees, positive sliding the assignment clockwise. At each multiple of 45 every arm sits squarely on one ramp; between those nodes the arms carry a blend of the two, and that’s where the in-between colors come from. This is the effect’s signature animated move: keyframe Map Spin from -180 to 180 and the colors make one full orbit while the geometry never budges — a rotating-prism read that layer rotation can’t fake, because layer rotation would take the streak directions with it. The dial’s hard range covers ten full turns in either direction, so a long continuous orbit is a single pair of linear keyframes. It only bites under AE Default; with routing collapsed to one ramp there is nothing left to orbit.

Two macro dials, 100 neutral: Master Amount multiplies Boost, Master Scale multiplies Streak Length. Ride a Master dial or the dial it folds, never both — the scaling doubles up.

Master Scale is the one you’ll use most. A star dialed in at 1080p is a star measured in pixels, so the same look at 4K wants Master Scale = 200 and nothing else touched; every per-arm multiplier rides along at its existing proportion.

Master Amount carries a trap worth knowing. It scales Boost before the exponential, and the factory default of Boost = 0 means zero times anything is still zero — the dial does nothing until you lift Boost off the floor. Set Boost = 10 or so first and Master Amount becomes a usable energy handle. Even then it isn’t linear: because the gain is exponential, Master Amount = 50 against Boost = 25 doesn’t halve the streak brightness, it takes the square root of the gain. Keyframe it for pulses and flare-ups, in smaller moves than a percent dial normally invites.