Reading the panels

Each row is one tick; each column is one snapshot, newest on the right. Brightness is resting size. A level that holds size draws a horizontal streak; a cancel ends that streak instantly, which is what makes a pull visible.

See the heatmap page for the full picture.

Because they were never going to be filled. Showing size to attract price and pulling it on arrival is ordinary behaviour in an electronic book. Watching it happen is most of the reason to look at resting liquidity rather than a candle.

The largest single resting order at that price, then the level’s whole book. One 200-contract order and forty 5-contract orders both total 200, and they behave nothing alike — the split is the difference.

The book carries small resting orders at almost every price all day. Painting them spends the colour ramp on liquidity that cannot stop price. The floor holds that churn below the visible range so the ramp goes to size that matters.

A half-cell lights up when one side is at least 200% of the diagonally opposite cell and the raw difference clears a contract floor. That second test is why 2 | 0 stays plain while 15 | 0 lights up.

Usually message filtering. Many feeds reuse the same message for volume and VWAP updates; some platforms count those as trades, so their volume runs high and their delta drifts. Chartveil filters them out before anything is counted.

Point of control is the price with the most volume in the range. Value area high and low are the edges of the band holding the configured share of volume around it — 68% by default, grown out from the POC one level at a time.

68% is the one-standard-deviation figure the convention is actually derived from; 70% is a rounding that stuck. It is configurable either way.

Aggressive volume arriving at a level without price moving through it — someone passive is taking the other side in size. Heavy negative delta at a low that holds is the textbook case.