Delta: analyzing aggressive traders
At the end of the last lesson I promised: you're holding the mechanics in your head — time to turn it into a number. That number is delta.
Volume only tells you one thing — how much. Five hundred contracts went through — so what? Whether that's a lot or a little, whether it was buying or selling — volume stays silent on that. Delta tells you the thing that actually matters: who was pushing harder inside the bar. Put simply, you take all the aggressive volume that went through at the Ask (market buys) and subtract all the aggressive volume at the Bid (market sells). What's left is delta. Positive — aggressors were buying; negative — they were selling. In ATAS this is both a standalone indicator, Delta, and a number highlighted in every Footprint bar.
Sounds simple enough: delta positive — go long. This is exactly where I tripped myself up.
When delta helps, and when it lies
Big positive delta — buyers are stronger, time to go long. I buy — and price goes down. How does that happen?
Delta didn't lie. It honestly showed that aggressors were buying. Here's the thing — it only sees aggression, only the people hitting the market. But on the other side there could have been a large limit seller, calmly handing out inventory to everyone rushing to buy. Buyers kept hitting it, delta kept climbing, and he absorbed all that pressure — so price didn't move. That's absorption. A big delta with price standing still isn't the buyer's strength — it's the strength of whoever's absorbing him.
In essence, delta without context is noise. Delta plus the full picture of the bar is a signal. And the full picture comes from the next tool.
The cluster — the same candle, but with anatomy
Here's the same candle you've seen a hundred times. And here it is again in Footprint mode. What changed? Everything.
The candle is the same, the price is the same — it just stopped being compressed. Every row in the cluster is a single price level inside the bar, and each row holds two numbers. The left one is how much was aggressively sold there, at the Bid. The right one is how much was aggressively bought, at the Ask. The difference between them is delta — not for the whole bar anymore, but for that specific level. And now it's clear why the price held above: you find the row where the right-hand number is huge — buyers were hammering it — and price didn't budge from that level. There's your absorber, right there on the chart. Footprint in ATAS shows this in every bar, in Bid/Ask mode.
Below, take a visual look at how, technically, these cluster bars are built up from buyer and seller trades. On the left is a classic Japanese candle, and next to it is the set of cluster levels: on the left (in red), market sell trades pile up; on the right (in green), market buy trades pile up. Click Next to get a new trade — it'll land in the correct price level and column.
The example also shows the horizontal levels clearly: their length relative to each other intuitively tells you where the largest cumulative values sit.
Imbalance and absorption: two situations
There are two situations in a cluster you'll run into in every other trade idea. Learn to recognize their shape once, and after that you'll spot them automatically.
The first is imbalance. That's a level where aggression from one side outweighed the other by three to five times over, and ATAS highlights those levels. What this means in practice: price passed through here without stopping — there was simply no one on the other side to object. When several highlighted levels like this line up in a row, stacked, that's an imbalance stack — the trace of a strong, aggressive push through.
The second is absorption — the same one from the second section. Enormous volume on one side, and price staying put. The exact opposite of imbalance: there, price flew because no one objected; here, it holds because someone very large is objecting.
Put simply: imbalance is the market moving through freely, absorption is the market running into a wall. Both signal a shift in dynamics, just in different words.
The candle as a result: direction, strength, confirmation
Footprint shows you the event. But an event inside a bar isn't the result yet. The result is what happened to price afterward.
The connection is simple, three steps. First — the candle's direction: if the aggression produced a result, you expect the bar to close in the same direction. Buyer imbalance — you expect a close to the upside. Second — body size, which is the strength of the reaction. A large body means a strong reaction. A small body on heavy volume is a warning sign: there was a sea of volume, and price barely moved, which means it got absorbed.
Third — confirmation, which is the next two or three candles. If they keep going the same direction, the scenario is alive. If they close against it, especially on volume, the scenario is broken: the event wasn't confirmed, or it got overrun from the other side.
Here's a rule I've worked out for myself: if an event in the cluster is going to matter, the candle and the next couple of bars have to show it. No confirmation — no confirmed setup. Don't fill in for the market what it hasn't confirmed.
Coming up: You now know how to read a cluster — on paper. But open Footprint in ATAS for the first time, and you'll be met with a flood of numbers and colors where you can't make out an imbalance or an absorption at all. In the next lesson we'll set up Footprint so these two pictures jump out at you on their own. Three settings — we'll leave the rest as is.