FPV Rates

Three variables, all interdependent:

• RC Rate is the master gain. With no expo, your center-stick sensitivity is 200°/s × RC Rate, and the whole curve scales with it — center and endpoints alike. (Above 2.0 a hidden multiplier kicks in, so each hundredth past 2.0 adds far more than the ones before it; a vestigial quirk of the firmware.)
• Super Rate multiplies the rate progressively with deflection, by the factor 1/(1 − x·super). At center stick it multiplies by exactly 1 — no effect — and grows hyperbolically toward the ends. It is how you obtain a fast full-stick roll without making the center twitchy. Max rate works out to 200 × RC Rate / (1 − Super).
• RC Expo flattens the center by bending the stick input itself: x becomes e·x⁴ + (1−e)·x before the rest is applied. Note well the entanglement — expo reduces your center sensitivity (by the factor 1−e), so adding expo for smoothness quietly changes the very thing RC Rate was setting.

The vice of the system: no variable reads directly in degrees per second, and each one perturbs the others. Change expo and your center feel changes; change RC Rate and both center and max move together.

The same curve family, re-expressed so each knob does one honest job:

• Center sensitivity is the slope at neutral stick, stated directly in °/s per full deflection. This governs how the quad answers small corrections — hover discipline, tracking shots, the micro-movements that dominate 90% of flying. It is entirely unaffected by the expo setting, which is the system's chief virtue.
• Max rate is the °/s at full deflection, stated plainly. This governs flips, rolls, and snap spins — 360°/s means a one-second roll; your 1200 means better than three per second.
• Expo shapes only the transition between those two anchors. At expo 0 the extra rate (max minus center) arrives on a quadratic ramp; raising expo defers it toward the end of the throw via an x⁶ term, enlarging the docile middle region at the price of a steeper cliff near the stops.

Center sensitivity is what your thumbs live in: too high and hover corrections oscillate, FPV footage jitters; too low and the craft feels leaden in tracking. Max rate is your acrobatic ceiling — freestyle pilots commonly run 650–1000°/s, racers a touch lower, cinematic work perhaps 300–500. Expo is a matter of taste: it buys forgiveness around center but concentrates the violence into the last fraction of stick, which some find disconcerting.

Once you find them, don't change them. Build muscle memory.