Turn highlights into starbursts
The detector measures luminance on a grid and selects points brighter than the threshold. Sparkle density and the seed choose which qualifying points receive rays, preventing every bright pixel from turning into a solid glow.
Ray size is relative to the image dimensions. Ray count distributes lines evenly around each selected point, and Warm tint shifts the added light between amber and blue.
The lens effect being imitated
Real starbursts come from light diffracting around aperture blades at small f-stops, which is why they appear on street lamps in night photography but not in casual phone shots. The effect grants that look without the tripod and long exposure, and the even ray counts mirror how blade pairs produce symmetric spikes.
Keeping ray size small and counts at 6 or 8 stays closest to what a real lens would draw. Large sparkles with 12 rays read as decoration rather than optics.
Select isolated highlights
Raise Highlight threshold to target reflections, jewelry, water, glass, or small lamps. Lower values may place starbursts across bright skies and pale walls. Reduce density before reducing threshold when the image contains many highlight candidates.
Large rays can cross faces or text even when their center lies elsewhere. Check the longest rays at the final composition before export.
Example: city lights at dusk
A skyline or string-light photo taken just after sunset is the ideal source: the lights are far brighter than the sky, so a threshold near 220 isolates them cleanly. Set density around 60 so some lamps stay plain, size near 3, and a warm tint around 30 to match tungsten bulbs. Then cycle seeds until the largest bursts land on the lights you want emphasized. If every lamp sparkles identically, the image reads as a sticker sheet; variation is what keeps it photographic.