Containment unit

With a ghost ensconced in a trap, the next step in ghostbusting is to transfer the trap to a containment unit.  Let’s look at the interaction.

The containment unit is a large device built into a wall of the old firehouse that serves as the Ghostbusters headquarters. It’s painted a fire-truck red and has two colored bulbs above it. As they approach, the green bulb is lit. It’s got a number of buttons, levers, and cables extending into it. Fortunately for purposes of discussion, Stantz has to explain it to their new employee Winston Zeddmore, and I can just quote him.


“This is where we store all the vapors, entities, and slimers that we trap. Very simple, really. Loaded trap here. Unlock the system…” He grabs the red door lever and cranks it counterclockwise 90 degrees and lowers the door to reveal a slot for the trap.

“Insert the trap,” he continues, and a sucking sound is heard and the green lightbulb goes off and the red lightbulb turns on.

Then Stanz pulls the trap out of the slot and is able to, as he explains, “Release. Close. Lock the system.” (Which he does with the lever handle.)


Next, he presses the buttons on the front of the device, starting with the top red one and continuing with the second below yellow, explaining, “Set your entry grid. Neutronize your field…” Then he grabs the red lever on the right-hand size and pushes it down. In response, the lowest push button lights up green, the red bulb above turns off, and the green bulb illuminates once again.

Stantz concludes, “When the light is green, the trap is clean. The ghost is incarcerated here in our custom-made storage facility.”


The interaction here is all based on the unkonwn ghostbusting technology, but it certainly feels very 1.0, very made-by-engineers, which is completely appropriate to the film. There’s also that nice rhyming mnemonic to remember the meaning of the colored bulbs, which helps Zeddmore immediately remember it. And course with the red paint and thick plates, it feels really secure and conveys a sense of pith and importance. Still, if they had a designer consulting, that designer would most likely tell them talk about a few aspects of the workflow.


First, why, if there’s no breakpoint between the entry grid and the field neutronizer, can’t those two be consolidated into a single button? A gridtronizer? While we’re on the buttons, why is that third one looks like a button but acts just like a light? If it’s not meant to be pressed, let’s make it an indicator light, like we see on the trap.

Similarly, why do they have to press that last lever and wait for the green light? I get that a variety of controls feels better to convey a complicated technology that’s been hacked together, and that would be appropriate for a user to understand as well, but it seems error-prone and unnecessary. Better would be another pushbutton that would stay depressed until the unit was doing whatever it was doing behind the scenes, and then release when it was done. It could even be consolidated with the gridtronizer.


But while we’re including automation in the process, why would the ghostbuster have to press anything at all? If the unit can detect when a ghost has been sucked in (which it does) then why can’t it do all the other steps automatically? I know, it would be less juicy for the audience’s sense of ghostbusting technological complexity, but for the “real world,” such things should be fully assistive:

  1. Insert trap (which gets locked in place)
  2. Watch the machine’s lights indicating its four steps
  3. Remove unlocked trap.

You might think for efficiency to have the trap removed immediately, but you really want the Ghostbuster’s attention on the system in case something goes wrong. Similar to the way ATMs/bancomats hold on to your card through a transaction.

Lastly, there should be some sense of what’s contained. In this scene there’s just Slimer in there, but as business picks up, it gets so jammed full that when EPA representative Peck recklessly shuts it down, it…you know…explodes with ghosts. Would a sense of the contents have helped provide him with a sense of the contents, and therefore the danger? A counter, a gauge, a window into the space, a “virtual window” of closed-circuit television showing inside the unit*, or a playback showing helmet-cam video of the ghosts as they’re being captured—would all help to convey that, Mr. Peck, you do not want to eff with this machine.


*IMDB trivia for the movie says this was originally included in the script but was too depressing to visualize so it was cut. But hey, if it’s depressing, maybe that would help its users consider the ethics of the situation. (Once again, thank you, @cracked, and RIP.)


When the Ghostbusters are called to the Sedgewick Hotel, they track a ghost called Slimer from his usual haunt on the 12th floor to a ballroom. There Ray dons a pair of asymmetrical goggles that show him information about the “psycho-kinetic energy (PKE) valences” in the area. (The Ghostbusters wiki—and of course there is such a thing—identifies these alternately as paragoggles or ectogoggles.) He uses the goggles to peek from behind a curtain to look for Slimer.


Far be it for this humble blog to try and reverse-engineer what PKE valences actually are, but let’s presume it generally means ghosts and ghost related activity. Here’s an animated gif of the display for your ghostspotting pleasure.


As he scans the room, we see a shot from his perspective. Five outputs augment the ordinary view the googles offer.

1. A plan position indicator (like what you see on a radar) sweeps around and around in the upper left hand corner, but never displays anything (even when Slimer appears.)

2. A bar graph on the left side that wavers up and down until Slimer is spotted, when it jumps to maximum. The bar graph adheres to the basic visual principle of “up means more.” The bar graph is colored with a stoplight gradient, with red at the bottom, yellow in the middle, and a bright screen-green at the top. Note that the graph builds from the bottom until it hits maximum, when its glow slides to the top to fully illuminate only the uppermost block. This is a special “max” mode that strongly draws the user’s attention.

3. There is a 7-segment red LED number display just below the graph, which you might think is a numerical version of the same data, but we only see it increment steadily from 03094 to 03051 during the first scan, then after a cutaway to Ray’s face, we see it drop to 01325 and continue to increment steadily until it hits 1333, where it remains steady and begins to blink. It hits this maximum about a half a second before the graph jumps to its max.


4. In the very lower left is a red mode label reading “KER,” which blinks until the numbers hit 01333 in the second sequence, when KER disappears and is replaced with a steadily-glowing green “MAX.”

What the heck is KER? I don’t think there’s any diegetic answer. Ker might be an extradiegetic shout-out to Rick Kerrigan, who was production supervisor for Entertainment Effects Group / Boss Film Studios for the film, but that’s just a guess. Otherwise I got nothin’. Anyone else?

5. In the lower right is a blurry light that blinks red until Slimer is spotted, when it blinks the same screen-green as the bar graph, sweep, and MAX label.

Narratively, this is a tone interface, that doesn’t add anything to the plot, and only helps us experience and understand how it is the busters do their busting. As a tone interface, making these changes would help improve believability without affecting the plot.


How to better support busting

The immediate improvements you could make to this as a “real” ghostbusting tool are fairly obvious:

  • Make the plan position indicator, you know, work.
  • Have the numbers match the graph, or, if they’re actually measuring different things, put the LED display on the other side of the view.
  • I’d change the graph color indicating no-PKE to black or dark gray. Red often connotes danger, and really, if there’s no PKE, you’re safe from the supernatural. Plus the blackbody radiation spectrum has a more physical reference and is therefore more immediate.
  • You could even lose the bar diagram—which requires looking away from the view—and replace it with a line around the view that changes color similarly. This puts the augmentation in the periphery.
  • Lose the distracting blinking red light entirely. It draws attention at a time when the Buster’s eyes need to be on the view, and it’s just duplicating information already provided in a better way by the graph.

But we can do those improvements better. In the augmented reality chapter of the book, I identified levels of awareness for these devices. The ectogoggles are an example of the simplest type, of sensor display, with the sweep giving an unfulfilled promise of the second type, location awareness. We can make even bigger improvements by considering the other levels, i.e. context and goal awareness.

Context Awareness

Context awareness implies a more sophisticated system with image recognition and display capabilities. Could the paragoggles help draw attention to where on the view the PKE is most concentrated, and how those readings are trending? Of course this wouldn’t be so important when the ghost is actually visible, but if it could lead his eyes to where the ghost is most likely going to be, it would be more useful and save him even the microseconds of an eye saccade.

A second aspect of context awareness is object or people recognition. If the goggles could recognize individual ghosts, the display be improved with some information about this particular ghost—or its category—from a database. What’s its name? What methods have failed or worked in the past to control it? Even if it doesn’t know these things, it can provide an alert that it is an UNKNOWN ENTITY, which is spooky sounding and tells the Ghostbusters to be on high alert since anything could happen.

Goal awareness

Lastly, they could be improved with goal awareness. The Ghostbusters aren’t birdwatchers. They’re there to capture that ugly spud. Can it help guide each person as to the best time to gear up the proton packs (or do it for them), where to position themselves as well as the trap, and finally when and where to fire? Certainly someone as scatterbrained as Ray could use that kind of assistance.