Chart lag versus order lag

[Fairman]

Chart lag versus order lag

The chart updates, and the price on the ticket looks the same. But the two can come from different places.

On some platforms, the chart receives a streamed price feed and the order ticket pulls from a separate source. When the market is fast, they diverge for a second or two. The chart looks smooth while the ticket shows a different price.

Clicking from a chart's one-click panel uses one of these sources, and the dealing window uses another. The result can be a fill that does not match the chart at all.

How to check: open a trade while recording the screen, then compare the chart price at the moment of the click with the fill price afterwards. Doing this on a few dozen trades reveals the typical gap.

A related point is that desktop charts sometimes get paused by system load, and the trader looks at a frozen picture without realising.

Has the chart ever frozen while trading was still active?