I've been playing The Division for a couple of days now and I've been a little curious about ECHOs.
Are they just one of those things that exist in the game for the sake of the story, or are they 'realistically possible', at least within the realm of the game?
Is there an explanation of how they work? Are they just a simulation from data captured from phone calls or something like that?
I'd like to add my understanding of this, through my gameplay experience.
An Evidence Correlation Holographic Overlay (ECHO) is a projected reconstruction of events at a location. It is created by the Agents shade tech and ISAC. When your system identifies a location with an ECHO, you'll see the scan start, as your shade tech system analyses the surrounding area and collates information at the scene.
The analysis seems to cover local debris, smartphone data, CCTV footage as well as an estimated projection of events, and also collates against known Division data. This data is all then converted into a visual representation of the scene, for the agent to investigate.
“It’s part of our agents’ tech set,” Barnard says. “In certain areas, it can basically accumulate all the digital data that’s available.” This includes everything from closed-circuit cameras to telephone conversations and more. All this info comes together to form a frozen three-dimensional moment, sometimes with audio attached. Agents can wander through these ECHOs, interacting with the image to find important elements that reveal valuable intel about your immediate surroundings, provide insights into the larger mystery of the pandemic that devastated New York, even nab some hidden loot. ~ Game Director Ryan Barnard
I would imagine that ECHOs are only available in areas where these is CCTV and a great deal of debris and/or local indicators, such as tyre marks indicating a car.
In the Police Academy mission, you do see that the ECHO system relies heavily on shade tech, and that it can be hacked to conceal details of the ECHO from ISAC. Agents also have the ability to record ECHOs using their own shade tech, as we see in the Unknown Signal mission.
If anything, I would look upon an ECHO as a visualisation of all available data about a location, not dissimilar to other video game crime scene investigations, such as Batman's investigation vision in Batman: Arkham Origins.
ECHOs are data artifacts combined by the SHD Tech device, the watch, in to a visual representation reflecting past situations. As far as I remember, this is explained a little with the very first echo you find.
ECHOs are "memories" of the area, if something interesting happened. For example, one particular echo shows a group of cleaners "cleaning" a guy who only suffers Asthma, and does not actually have Smallpox.
It is form of background information to get to know who are the good guy, sand who are the bad guys. In some cases, it shows crucial story information, such as when you use ECHOs to track Agent Lau's sister.
Take the time to investigate these as they provide story and background of how everything evolved to the point where the second wave has to be called.
