Optimization guide
Optimizing longevity, projection, and balance
The AI Lab is where you refine a formula against goals rather than build it material by material. Presets give you a tested starting point, and the optimization toggles reshape the note structure to favor how long a scent lasts, how far it throws, or how evenly it sits.
Longevity versus projection
These two qualities pull in opposite directions, which is why they are separate goals. Longevity is how long the fragrance remains detectable on skin; it comes from heavy, low-volatility base materials and fixatives that evaporate slowly. Projection (or sillage) is how far the scent radiates; it comes from volatile, high-impact top and heart materials that diffuse into the air.
Pushing longevity hard can mute a fragrance to a skin scent, while maximizing projection can make it loud but short-lived. Most well-rounded perfumes find a deliberate compromise, which is why you can enable both goals and let the optimizer balance them.
What fixatives do
Fixatives are materials that slow the evaporation of the whole blend, anchoring lighter notes so they last longer. Classic examples include ambers, resins, certain woods, and musks. Beyond extending wear, they smooth the transition between the top, heart, and base so the fragrance evolves gracefully instead of collapsing.
When you boost longevity, Scentena raises the share of these base-tier materials and rechecks that no single one exceeds its IFRA cap.
Reading the assistant insights
After each generation the lab summarizes the note split and the dominant scent family. This is a quick diagnostic: a citrus theme that comes back base-heavy will smell muddy, while a woody theme with almost no base will feel thin and disappear quickly.
Use the suggested additions to round out a family that is under-represented, then re-optimize and compare. Iterating two or three times usually lands a more coherent result than trying to get everything right in a single pass.
Using presets
The presets bundle a theme, concentration, and method that are known to work together — a fresh summer EDT, a rich amber parfum for evening, a cozy gourmand EDP. They are a fast way to explore a direction before you start tuning, and a useful reference for how the parameters interact.
Frequently asked questions
- Should I enable every optimization goal at once?
- You can, but the goals trade off against each other. Enabling longevity and projection together asks the optimizer for a compromise; balance and safety modes add structural and stored-limit checks, but do not establish compliance. Experiment, compare the note split, and independently review the materials each time.
- What is sillage?
- Sillage is the trail of scent a fragrance leaves in the air around the wearer — essentially its projection. High-sillage perfumes are noticeable from a distance; low-sillage "skin scents" stay close to the body.
- Why does my optimized formula still show IFRA warnings?
- Optimization shifts material ratios to hit your goals, which can push a restricted ingredient toward an available stored limit. Treat the warning as a prompt to stop and review the exact material, current documents, category, and total constituent contribution before making a trial.
- Do presets lock my settings?
- No. A preset just fills in a starting theme, type, and method. Every parameter remains fully editable, and you can re-optimize as many times as you like.