Special FX Arts and Crafts 201 - Lie Detectors


Sunday, July 04, 2004


As I mentioned in the previous entry I've been working on a friend's project; another prop the script called for was a "verifier," a portable lie detector that is supposed to shock the subjects when they lie (as well as shock the person holding the unit to administer the test).

Since the writer's previous experiences with the wonders (and costs) of adding effects in post-production made him determined to do as many effects live (on-set) as possible, this meant that my prop actually had to do something -- it needed to make noise and flash, not only so the audience could see that the characters were being shocked but so the actors had something to react to.

The first step was to find a suitable box to build everything into; since I had an idea on what to use for the flash effects (more on that later) I didn't want to use something metal so that left plastic or wood. My first thoughts were of tackle boxes (too big, too small, or required lots of work to cut away internal partitions) or craft boxes (see previous), and I couldn't find anything in wood...it took the wonders of television advertising to send me the sign I'd needed...namely, the Lock and Lock food storage system!

One of their containers comes with a handle and was big enough, yet not too big...so the first problem was solved.

In order to keep costs to a minimum, I decided to cannibalize flash units from a couple of disposable cameras instead of purchasing self-contained strobes; I soldered wires to the charging and trigger switch connections so I could hook everything together. I also needed to add buzzers for the audio cues, and those had to be wired with the flash units so they would fire simultaneously.

The writer and director also wanted some sort of a retractable "power cord" for one of the characters to get tangled up in, so I needed to think of how to put that in; I decided that a small retractable leash should fill the bill, so I picked one up.

Now, without further ado, are some pictures of the completed verifier:

The large red switches on the bottom are the main power activation for the flash and buzzer, one for each side. Just below the buzzers at the top, you can see two LEDs that flash when turned on; they weren't specifically requested but I wanted to make the prop look "busy."

A side view showing the opening (trimmed with vinyl tubing) where the actors would stick their hand in; at the upper right of the opening you can see some of the wiring harness.

Here's what the inside of the verifier looks like; most of the internal components are mounted on the lid. The large black boxes are battery packs for (top) LEDs and (middle) buzzers; the flash units (bottom of lid) had their own battery.You can see the leash (with handle removed) in the bottom of the box, and the switches just above the leash are used by the actors to trigger the effect.

While it was decided at the last minute that the power cord gag wasn't practical, the scenes with the verifier worked out extremely well and everybody was thrilled with how my prop worked. I don't have any footage from the production, but I have made a QuickTime clip (1.9 MB) to show its operation -- however, due to the encoding, it only shows one side flashing.



Special FX Arts and Crafts 101 - Mutant Garden Gnomes


Sunday, July 4, 2004


I know it's been a very long time since I uploaded a new entry but there hasn't been a lot of new stuff going on until recently; I just finished 4 weekends of working on a sci-fi comedy that a friend wrote and now that I have a little bit of breathing space I can take the time to show you some of the things I've been working on.

This entry will cover garden gnomes -- but not your average gnome; the script called for rocks in the shape of weather-worn garden gnomes, specimens to be picked up on an expedition to an alien planet!

Since I really didn't want to start from scratch, I decided the easiest method would be to get some "real" gnomes and alter them as needed, but I ran into a snag -- the one time I actually wanted gnomes, I couldn't find the little shits! After a fair bit of searching various garden stores, home renovation centres and craft stores I managed to locate these three gents:

(Before anybody accuses me of peddling gnome porn, that guy in the middle is riding a squirrel for transportation purposes)

As you can see, the gnomes are very detailed -- too much, in fact, for my purposes. Time to break out the Dremel and start grinding them down:

This picture was taken fairly early in the grinding process and as you can see by looking at the belt of the gnome on the right, some parts were thinner than others and I went completely through so, after the sanding, came the Spackling:

After the Spackle had dried, the gnomes were sanded down but they still needed more of a smooth, eroded look so I dipped them in plaster:

After another sanding, it was time for the final touch...painting them to look like rocks. This could have been difficult but thanks to the wonders of modern technology, you can buy "rock finish" paint in a spray can!

Here's how my little friends wound up:

So there you are; three "rocks" that are recognizable as garden gnomes, yet not too detailed.

Tune in again sometime reel sune to see how a food storage container and a dog leash (among other items) are turned into a portable lie detector!