Air is the easy way in, and the default. Leave your screen where it is, mark out a
keyboard-sized rectangle in the air in front of you, and play that. Nothing to reposition, and
you can still see the screen — which you cannot if the lid is tilted down at the desk.
Desk gives you a real surface to feel, which is steadier once you are used to it.
Tilt the screen down until the camera sees the desk and your hands resting on it; a lid at
roughly 45° is the sweet spot. It reads a tap by watching your fingertip travel and then stop,
so it wants to see that travel: almost edge-on and directly overhead both give it less to work
with.
Switching between the two re-opens calibration, because the plane you marked in the air is
not the one on your desk.
Mark out your playing area by clicking its four corners in the camera view —
far-left, far-right, near-right, near-left. Click any corner afterwards to nudge it, and use
Reset to start the four over.
On Desk, click where your fingertips will be, not where the desk's corner is.
The instrument measures fingertip positions, and a fingertip resting on the desk sits a
centimetre or two above the desk's own surface — on a low camera reaching far across the desk,
marking the surface instead can put a key out by one or two. A centimetre of allowance towards
yourself at the far corners is all it takes. Air mode has no surface underneath, so this
doesn't apply.
Calibration is remembered. Redo it if you move the camera, change camera, or move the desk.
Using an external webcam? Pick it from the Camera list — a desk rig usually isn't the
built-in one, and changing camera means re-marking the desk.
Playing
Tap the desk like keys, with your fingers. Notes fire the moment your fingertip stops
against the surface — the same instant a real key would sound. A note needs the finger to reach
for the desk; dropping your whole hand rigidly is treated as putting your hands down, not as
playing, which is what keeps resting between phrases silent.
How hard you strike is how loud it is, and harder notes are brighter as well as louder,
the way a real hammer excites more of the string.
Both hands play independently. With the register split on, your left hand sounds two
octaves down, so the whole surface is a bass keyboard for it and a treble one for your right.
Resting your hands on the desk is silent — only a genuine strike speaks, and a hand simply put
down flat has no reach of its own, so you can leave your hands down between phrases.
Damping decides how long notes last. Pedal lets every note ring out like a piano
with the sustain pedal down. Follow finger drops the damper when you lift off, so how long
you leave the finger down is how long the note lasts — which is what makes staccato playable.
Getting notes you didn't play? Set Play with to Index only. Tap a note
with one finger and its neighbours come down with it; the instrument works out which one
actually reached, and mostly gets it right, but one finger per hand removes the question
instead of answering it. The switched-off fingers show as faint outlines so you can see the
tracker still has your hand. Switch back to All fingers for chords.
If taps aren't registering
Check the track figure in the header. Below about 20 detections a second a tap can begin
and end between two looks at your hands, and no amount of tuning recovers it. Closing other
GPU-heavy tabs and enabling hardware acceleration is the fix.
Strike, don't press. The detector is looking for a finger being stopped by the surface,
not for a finger arriving at it. A slow deliberate press is deliberately silent — that is what
lets you rest your hands down.
Keep your fingers reasonably extended. A curled finger is ignored, which is what stops a
fist or a wrist landing from playing a cluster.
If the keys look like they're in the wrong place, the calibration has drifted — mark the desk
out again.