Creating a guerrilla drive-in from scratch:
The mobile movie project has grown far beyond my wildest imagination.
I watched as my hair-brained concept first evolved into something for friends to enjoy, and then quickly sparked an international movement.
With humble intentions in saying so, now people from around the world are asking me how they can too start their own. Here we are and this is that.
What is a mobmov?
If you've gotten this far I probably don't need to answer this question. But in case you're completely new to the concept,
and decided you want to start a mobmov just because you liked the name “mobmov”, here's a quick primer:
Definition of a Mobile Movie
A "mobile movie" or mobmov for short, is quite simply a drive-in that drives-in. Participating in a mobmov is very similar to attending a drive-in from the days of old, except now the projector is located inside and powered by a car, and the audio is piped in stereo over the FM band to the attendees' cars. As a mobmov driver, you assemble the kit, decide on the movies, and announce your shows to friends and the community at large. Then everyone assembles in a dark place with a big wall, and you watch a movie. It's a new technological twist to a nostalgic idea.
Why start one?
If you're a geeky hacker like me, a large part of the satisfaction of running a mobmov will come from actually setting up the kit.
If so, this tutorial will be fun, if not disappointingly easy. If you're not, it's my hope that this tutorial gets you through
the painful bits so you can just enjoy the end product!
The challenge of creating something completely new was what inspired me
to do this in the first place. But when word spread and membership widened, I realized that the real reward came from meeting all the
interesting people who came to my shows. The mobmov attracts a friendly lot, full of stories and ideas. If not for this project,
I wouldn't have gotten to know them. The mobmov is a community experience, a place for people to gather and share in the splendor of
the great American movie. That sounds like a pretty worthy hobby to me.
I'm no expert nor am I a teacher. I'm just a guy who got lucky with a bunch of expensive equipment, doing something crazy.
It is very likely that by following these directions, you will break expensive things, void any and all applicable warranties,
and may even risk personal injury. Please always use your best judgment and skip any directions that sound too complicated or dangerous.
Additionally, running a mobmov opens up a legal can of worms that I will do my best to explain below but do not interpret my writing
this tutorial as a personal endorsement of such activities. You must respect copyright, ordinance, and trespassing laws. I can't be
responsible for anything you do as a result of reading this tutorial I write this for informational purposes only, for free, without stated warranty of outcome.
Affiliate Links & Ads
Within this tutorial I make several product recommendations, often followed by links to those products online. A few of those links are
affiliate links, meaning that if you click them and buy the product, the mobmov gets a small commission. I feel it's important to clarify
this first and foremost, because I make these product recommendations not based on the commissions, but rather, on the merit of the products themselves.
I use most of the products myself, and I've chosen merchants that I've ordered from in the past and trust. That said, these links will (hopefully)
allow me to expand and improve this tutorial, as well as support the mobmov project. Please feel free to take my product suggestions elsewhere,
but I'd really appreciate it if you'd consider using those links. Your call. I just didn't want to do it sneaky-like.
I'm going to assume that coming into this you know relatively little about electronics, cars, power inversion, or projectors, because I didn't when I built the first mobmov. If you're an expert in these areas, please excuse the occasional condescension, and kindly correct my (sure to be many) mistakes! As they say, everything I needed to know I learned in kindergarten, but they didn't offer an electrical engineering course in my kindergarten.
What follows is a list of components you will need to set up a mobmov of your own. You can substitute components as you see fit, this is just a list of what I use and which works for me. Cyberpunk urban theatre, here we come!
It seems a little silly to list it first, but a car is really the vital element to any true mobmovian set up. You could set up an outdoor movie like the Santa Cruz Guerrilla Drive-in with a bunch of marine batteries and a shopping cart, but that isn't a mobmov, now is it?
The ideal car will have a large windshield, and either a large flat dash on which to place the projector, or have some other way of mounting the projector within. In my small SUV I use an stool from IKEA, sitting between my dash and the passenger seat. I *don't* recommend mounting the projector on the roof or anywhere else exposed to the elements though you will get maximum light output, this method takes longer to set up, and is more dangerous to your equipment because of the moisture and dust. Projectors are very fragile things.
Your car also must have a powerful alternator capable of generating a constant 300w or so. This is where my expertise fails miserably, and my luck must have really cut in. My alternator is theoretically only capable of generating 150w (according to those I asked at Toyota), but it worked anyway. I'm just lucky, but probably still managed to void my car warranty, so you should be more careful and do your research.
I leave the car running during a showing not doing so will result in a dead battery in about an hour's time. If you want to figure out how long your battery might last, here's a useful equation:
So if your battery is rated at say- 40 amp-hours, at 12V, that's 12 x 40, or about 480w. I know this is probably way over-simplifying things, but that suggests to me that if my equipment uses 240w, I will have a runtime of about 2 hours. Here is an interesting tutorial on batteries that might explain this a little better.
The bottom line though is that you will not have a runtime of two hours on a standard car battery for a mobmov set up. You will drain your battery, and car batteries lose their strength each time they are drained. You do this a few times and your battery is down for the count. Marine batteries are much more powerful, but you'll still need a couple for a full-length feature. The easiest (if not environmentally-friendly) solution is just to leave your car running.
For the sake of comprehensiveness, the car I use is a Toyota RAV4 2004. Supposedly the RAV4 alternator got an upgrade in 2003, so maybe this helped me. Like I said, this is not my area of expertise, so if someone reading this wants to chime in, please do. The RAV4 is quite literally perfect for this sort of thing, due to the large interior and relatively flat windshield. I'd bet one of those Toyota/Scion xB box cars would work even better. Kudos to the person who sets this thing up in a classic Chevy convertible that's what I'd do if I didn't need a daily driver.
Thinking of all this power gobbledygook brings me to the subject of how to power your kit. Admittedly the least sexy of all the components, but probably the most important, is the power inverter. Like so many things these days, power inverter packaging makes all sorts of crazy claims about the product's attributes. From personal experience, most claims about power inverters are flat-out false. For example, be weary of “peak” output, the number they often list in glittery bold red, as it is always followed by a tiny grey asterisk. This means the inverter can't actually achieve this power rating for anything longer than a few seconds. Look instead for “continuous” power rating (usually in small print), which will be an indicator for your total power output. It's safe to assume they also inflate this figure. I tried several 800w inverters that didn't work before finding the Coleman I now use.
You should always buy more than you need in this department. While your system may be capable of running on 300w, buying a 300w inverter will assuredly not cut it. My set up requires about 240w, and I have an 800w inverter. In hindsight I probably would have just gone for the 800w for the flexibility. Inverters are pretty cheap, so going for a high quality one is best. After all, if something goes wrong here you might just fry your entire kit!
It's imperative that you grab one that connects directly to your car battery. Do NOT attempt to run your projector off your 12v socket. It will not work and you will blow a fuse or worse. The amperage is just too high. To figure out amps, divide wattage by voltage (see above equation). So if your projector takes 240w, at home you only need 2 amps (240/120), but in the car you'll need a whopping 20 amps! (240/12). Your 15amp fuse will not enjoy this punishment. Believe me, I have the burnt-out fuse to prove it.
Your next question now is: how in the world am I going to show the movie out my windshield with my hood propped up? This depends. I took my car down to my local Best Buy for a quick install. If you do this, buy a battery wiring kit online, then go down there and have it installed (their kits are overpriced). They'll drill or whatever they have to do to get the inverter in your car hooked up to your battery. I placed my inverter under my passenger seat, a space that also fits the DVD player. The install set me back a whopping $30.
I use and recommend: Coleman Power Inverter 800 ($85-100)
Or a power generator: Yamaha Power Generator 1000($650-$900)
For a really good show, you're going to need a really good projector. Luckily, projector technology is advancing at a rapid rate with prices plummeting and specs skyrocketing, it's getting harder to go wrong. That said, there are specific features that will make your job as a mobmov driver much easier and so make your shows all the much better.
First, you need some really high light output (rated in lumens). This all really boils down to your two budgets the wallet sort, and your power budget how much total wattage you can sustain without giving your car battery a heart attack.
Let's start then with what I know works. I've had success with Epsons and InFocus projectors - generally choosing one in the upper end of the consumer spectrum. Costing a little under $1,500, you can expect about 2000-3000 lumen output and some nice features. It's amazing to me how far the technology has advanced since 2004.
Granted, consumer projectors like the Epson are still distant cousins of the 15,000 lumen projectors you see at rock concerts, but you don't need that kind of light output. If anything, 1200 ANSI lumens is a good minimum. It's a comfortable minima certainly, but if you go much lower, you'll experience problems. I started out with the InFocus 4805. A very good projector certainly, but at 750 lumens, I found that even a bright street lamp washed out the colors. The Epson's 1500 lumens is pretty gosh darn perfect by comparison; while pre-sunset shows are still out of the question, twilight isn't as much a problem as it was with either the InFocus or the Panasonic. Though I can only imagine (and dream) how a 3000 lumens would look, I'm sure it would be sublime.
Be *very* weary of lumen ratings though. Worse than power inverter output ratings are lumen ratings it's safe to assume most manufacturers inflate their lumen ratings by 100% or more. Always check online reviews at projectorcentral.com, projectorreviews.com, or Consumer Reports, all of which measure 'actual' light output. For example, the Panasonic comes in at about 900, and InFocus at about 400. Epson tends to be very honest about their ratings, and sure enough it comes in at 1450. Be especially wary of "business" projectors, which are cheap but have high lumen ratings. Oftentimes, after you adjust them so you can actually see the image, their lumen output is much lower.
LCD or DLP you ask? This does seem to be the question at the moment when it comes to projector technology. On one side, you have DLP, which traditionally offered better contrast than LCD. Pictures produced by LCDs would appear muddy in a darkened room. Today, the playing field has all but leveled out in this area, with the introduction of fast dynamic irises, which adjust to the brightness of a scene. The Epson, a modern 3-LCD projector with a dynamic iris, has 5000:1 contrast, which is ample to my discerning eyes. A similar LCD projector, the Mitsubishi HC3, produced only four years ago, has a fairly yucky 500:1 contrast. While lumens should remain your highest concern, having better contrast means better color on less-than-optimal viewing surfaces (like that warehouse wall you have your eyes on). But in my humble opinion, LCD and DLP technologies are pretty much even. You might hear some complaints about a DLP "rainbow effect", but other than that, the differences in price/features you saw in the past have pretty much leveled out. So choose whatever one fits your needs and budget. Read this article for an even more detailed explanation of the differences you can expect.
Going back to my own projector, and trying hard not to sound like a car salesman, it extrudes far more virtues that make it ideally suited for the mobmov kit. First, it has a 16:9 (WXGA) widescreen ratio a *must* for that cinema experience. Most new projectors have it, so if you can afford it, choose a 16:9.
Second, it has a very flexible lens. Not as flexible as the Panasonic of yore, but it can also lens zoom AND lens shift, which is pretty unheard-of among consumer-level projectors. What does this mean? Basically it allows you to plop your projector on your dash or roof, drive up, and aim lens anywhere on the wall without having to lower the psi in your front tires to get the image centered. This makes set up easier. The zoom is particularly helpful, because it will allow you to park at different throw lengths from the wall, depending on where you're showing. I'm not kidding when I say I think this combo is even more important than a high lumen rating, at least for a mobmov kit. It also features keystoning, a handy feature which allows you to project onto less-than-flat surfaces while still retaining a square picture. Pretty amazing to see. Imagine watching a perfectly square movie on a hill. It almost looks 3D! Though I must say it is tough taking Al Pacino seriously with grass growing from his head.
When looking for a projector that will make your job easier, look for at least 1.5x zoom lens, horizontal and vertical lens shift, and keystoning.
At 20dB, it is also difficult to hear, meaning it's easier to watch the movie in your own car. I always advocate inviting yourself into other peoples' cars instead, but this leaves you the option in case they smell funny. Most projectors have noisy fans that just spoil the experience.
Lastly, it has low power consumption. At 200w, it's a sipper in a world of gulpers. Most projectors will use 300w or more, which may just push your power generation capabilities to their limits.
You actually have a lot of options in this realm. In fact, I currently project movies using my laptop. Laptops are great for this purpose because you have lots of software options, they don't use much power, and you have a second screen on which to preview your material before projecting it. But really any DVD or DivX-enabled player will do. I used to use and still recommend the RjTech 250PDVX. First, it's quite small, and has other features that make it ideal for this mobmov thing. Second, it plays DivX-encoded files from your computer, in addition to plain-jane DVD disks. This gives you a lot of flexibility and options when it comes to presenting your shows. For example, during each showing I have an opening title, a cartoon, and an intermission in the middle. Short of actually pressing pause in the middle of a DVD, DivX is the only way I could achieve this. I think it really adds to the professionalism of the whole event opening with mobmov logos and a warm welcome. You can of course play DivX files on any laptop.
You don't really need anything specific in a DivX player, other than the ability to output to s-video or some other high-quality video source (component, VGA, HDMI). A headphone jack is a small plus, because it takes out the need for an RCA-to-headphone converter. If you can, find a DVD player with a 12v car adapter, which will just reduce the load on your inverter.
If you do get the RjTech unit, make sure you upgrade to the latest firmware on their web site. Mine came with an early revision that had problems reading some DVD-R discs. Upgrading the firmware fixed it.
I use and recommend: using an old laptop or the RjTech 250PDVX
There's a few pitfalls I can save you from here. Firstly, clear your mind of everything you know about FM transmitters, and rid yourself of that silly notion that your Griffin iTrip transmitter is going to cut it. That little guy barely makes it to your own car antenna from within your car do you think it's going to get as far as two cars over? Five cars? Not a chance!
What you need is a “semi-professional” FM transmitter. To that end, I only know of one brand that works, called Ramsey Electronics. And unfortunately, we've suddenly landed ourselves in the land of uber-geeks, which actually know how to build electronic kits piece-by-piece. Some online stores sell pre-built units. You can also find them on eBay.
As for power, I use the FM25b model, which gives about 150ft or more of perfect signal. I've never discovered the true limits of this unit, and no one has ever complained about a scratchy signal. The FM30 has the same range and adds electronic tuning, so you can more easily change the radio station you're broadcasting on. The FM25b, by contrast, requires you to open the case and flip some (easy) dip-switches. If you live in the city and change locations a bunch, get the FM30 to avoid hitting any existing signals.
But there's no need to grab any more power output than you get with the 25b. In fact, you should use as low powered a transmitter as you need, because causing more interference than necessary will result in problems with the FCC.
That said, you should be clear about all FCC rules before setting up your kit. It is my understanding that you are okay if you are not interfering with any licensed radio station in the area. This can be very tricky though, because some especially on the lower part of the 88 bandare really weak and require large antennas to pick up. If your transmission interferes with any of these and you are reported, the FCC will hunt you down and revoke your after-dinner TV privileges for a week! Or something like that.
If you can, purchase a car adapter for your FM transmitter. If you run your FM transmitter off your inverter (I do), you'll need to wrap your audio wires in a ferrite audio noise interference filter (here's one from Radio Shack but there are many other types and models) that you can get from radio shack for about $5. If you don't, you'll hear a loud hum over your audio.
But all your radio transmitting power is for naught if you don't broadcast from *above* your receiving antennas. FM expands like an umbrella underneath the transmission antenna, so placing the transmitter inside your car will result in severely reduced transmission strength. That said, you have two options. For easiest set up and to protect your transmitter from condensation, you should buy an external antenna to attach it to the outside of your vehicle. Ramsey makes many such antennas that would work, but you can also fashion your own for next to nothing using tutorials available on the web (such as). I actually take the less recommended slash ghetto approach, by setting the transmitter on the roof of my car. I've actually driven off with the transmitter on top of my car, so you can start to see why this is not my top recommended solution.
If you have some technical know-how, you might consider building a transmitter of your own and saving a few bucks. Rico Thunder from the Santa Cruz GDI offers us this link as a place to get started.
I use and recommend: Ramsey FM25b or FM30
Setting it all up
There's really no magic to connecting all these components together. Video out to video in, audio out to audio in, power out to power in. That's about it. Electronic interference has suddenly become your worst enemy though, thanks to that fiddly FM transmitter, so when making your purchases keep in mind that shorter, thicker cabling is better.
Congrats, you've got it all set up. If you're steamed and need a break before continuing, these photos are pretty fun and entertaining.
Running a mobmov
I don't profess to have arrived at the “best way” to run a mobmov. But, after two dozen or so shows, this is how I do it now, and it seems work well.
Getting the word out
I announce shows online through a mailing list software I created. If you're interested in using this software, sign up to be an official mobmov chapter. I'll set you up and give you access to the member control panel. It's all free.
You can of course try new inventive forms of advertising that I have yet to attempt why not post some appropriately campy posters around town? Believe it or not, some movie licensors actively prohibit some forms of non-theatrical publicity, so be careful.
Getting set up
I generally try to arrive a few minutes ahead of time, mostly because I know if I do, I'll actually arrive on time. My particular set up is so easy to connect though (most of it stays connected), that it takes me all of about 3-5 minutes to get going. This is actually part of what I think makes the mobmov such a success - if it took me 30 minutes to haul out a projector and batteries, I'd do it a lot less often.
While I'm setting up, I have a mobmov welcome title showing from my laptop, so people know that “this is the spot” and what radio station to tune to. Sign up to be a chapter and you'll get free access to these files.
I usually park in the front-center, and cars will generally line up to both sides first, and then to the back when the front row fills up. My car is rather tall, so that limits the number of people that can park directly behind me.
I'll generally wait 5-10 minutes after the announced showing time. During this time I show an intro title with information on the movement, and play some good music in the background to let everyone figure out the radio reception and talk to me if they need help. There's never been a problem with reception, but I always like to take the time to introduce myself to new cars anyway and make sure everyone is good to go.
Then I start up on the openers. These usually consist of one or two old-school B&W commercials and a cartoon or other short film. Sometimes this is a newsreel. All of these can be found on archive.org in the public domain. The movie ends up starting about 20 minutes after the announced showtime, which seems to work for everyone. The openers play a large role in setting up the aire of nostalgia and I've gotten a lot of good comments about them.
In my opinion, the intermission is really the most vital component to an enjoyable mobmov experience. About mid-way through the movie (usually at a cliff-hanger if I can find one), we break for a 10 minute intermission. A title pops up with some good music, and people are encouraged on-screen to get up and meet people, say hello to the driver, buy some snacks, and donate if they can. Fueled by such an intoxicating atmosphere, I find that people are anxious to do all of this with gusto.
I usually tell people on-screen during the intermission that there is a donation mug on the lead car, and ask them to contribute a few bucks to help support costs like gas and projector bulb replacement. People have been quite generous in the past. Be wary of charging mandatory admission though not only will this water-down the plebeian atmosphere of the whole thing, but may get you in trouble depending on your licensing agreements for the movie you're showing.
Selling snacks is a good way to recoup some costs without directly asking for money. I usually head down to Costco or Target the night before and grab a big bag of pretzels or assorted chips, along with some candy bars and other movietime snacks. Recently I've started giving out the chips for free (they cost me hardly anything) and sell the candy bars and soda for a buck apiece. This gets people down to the “snack bar” to buy the other stuff, and I think it makes them more generous with the donations. Plus, it's just a good thing to do. If you figure out how to get fresh, hot popcorn to a showing, let me know! That would be the killer mobmov app.
Running a mobmov does touch on a few legal issues. I will relate to you my personal understanding of the issues at hand. Of course, don't take my word for it, and always check with the appropriate authorities before actually running a mobmov of your own.
If you're running a mobmov, it's very important that you respect them. A mobmov can attract a lot of attention, and as the movement grows, the powers that be may take a glaring notice of not just you, but mobmovs in general. If we do this thing right though, the movie studios will have more reason to cooperate with us and might even appreciate what we're trying to do.
The bottom line is that you must respect the copyrights of the movies you show just because you aren't charging admission doesn't mean that you can show the movie without paying for its use. I personally have had the best luck contacting the studios directly. They are usually so excited by the idea, that they approve it for a limited audience without charging any fees. Your mileage my vary; mine has. As the novelty of the mobmov wears off, it may also become more difficult to get free showing rights. A lot of movie studios will just direct you to an independent licensing house, which is usually a dead end. Most movie licensing houses do not permit outdoor shows of films, even if you offer them lots of money. Without attempting to preach, it's a very silly and outdated system.
Swank Pictures is the *only* movie distributor that I know of that will license non-theatrical outdoor shows (non-theatrical means that you don't charge admission). They have a bazillion rules, including a stipulation that you must show in a constant location. Licensing fees, though, are quite affordable: ranging from $100-$300 depending on the movie. Read the rules that govern outdoor movies. You should contact them to set up an account if you wish to take this route.
That said, there are numerous sources of freely available creative commons movies and media available online. Check out archive.org for listings of such movies.
It is my layman's understanding that the FCC permits unlicensed broadcasts as long as they are under 1W and do not interfere with existing radio stations. But this is a very simplified understanding, so please, don't take my word for it, and check this with the FCC rules. If I'm incorrect, I'd appreciate an e-mail so I can correct myself.
From my experience, the police are not too concerned about mobmov activities. It is very clear at a glance what we are doing, and that it is safe and legal. But I always bring along any licensing documents to prove myself just in case of inquiry.
In the course of running my own mobmov, there have been two police drive-bys. Both times, the friendly cop slowed down for a harrowing few seconds, took shape of the scene, and then drove on their merry way. I suppose that at 10pm at night in a dark area of town, we really are the least of their worries. If anything, our presence makes it safer. However, there are three main points to keep in mind to minimize the possibility of attracting (negative) police attention:
- Noise pollution: One of the important features of a mobmov is there is usually a very low level of noise generated. Outdoor movies, on the other hand, must blare their audio over loudspeakers. This sort of distraction is the kind of thing that will attract the attention of the police, but as a mobmov owner you can be less wary. Even still, a mobmov showing can be very noisy depending on the environment and the patrons. Keep an ear on it and you should be okay.
- Light pollution: Always be very keen about where you show your movie. I'd highly recommend against showing in a residential area or worse- on a residential building. This can generate some very strong complaints, and might get you fined for disturbing the peace.
- Trespassing: If you will be inviting cars into a parking lot or other space owned by someone other than you, make sure you get permission to show there first. We've had reasonable success projecting onto dimly lit walls from the street, so that no one is parked on private property. As far as I'm aware, there is yet no law prohibiting trespassing with light. Please be aware that any public property, such as schools or parks, are usually heavily guarded against after-hours trespassing and abuse. You will very likely be dispersed and questioned if caught showing a movie on public grounds. When in doubt, check with the city or your local police.
Our friend Rico has a good suggestion: if you will be showing where there may be neighbors, you should consider informing them ahead of time and inviting them to attend. Not only may you grow your audience, but if people know about it and feel included they'll be less likely to cause a fuss.
With this tutorial in hand, I hope that you're able to successfully establish a roving drive-in of your own. But I also sincerely hope that you choose to become an official mobmov chapter linked on our web site there's no cost to you, but having more chapters means an easier advertising job for all of us. I can't tell you how many people I've had to disappoint by saying I didn't know of any drive-ins in their area! It's also my optimism that expects that some people that read this will be inspired to contribute other important things to the movement, such as new guides, sparkling video titles, easier movie licensing avenues, or even mobile popcorn makers. We can do this better if we're all waving the same banner.
I hope you found this write-up useful. If it did indeed save you some time and money (after all, you didn't have to blow the fuse, did you?) please consider passing on a modest donation to the movement. Anything you can offer (how about $5 from your first donation collection?) will be appreciated and cherished.
Check out our guide on instructables.com
If you need help or have something to say, please post it to our forum for help and advice!
Now get out there and transform those abandoned warehouse walls already!
Credits and Appreciation
Special thanks goes to my friend Jonathan Hey for generously lending his ample artistic talents to this endeavor. He drew the sketch you see at the top of this tutorial and created the playful mobmov jingle you hear at the beginning of every show. I'd also like to thank all those who've been with me since the beginning, egging me on and giving me great ideas - my friends Menzies Chen, Kim Knight, and Ray Kohno come to mind. Menzies deserves particular kudos for actually coming up with the term "mobmov"! Also, thank you to Rico Thunder of the Santa Cruz Guerilla Drive-in, not only for inspiring me to begin this project in the first place, but for all his support and assistance along the way. Lastly, I'd like to thank all those who have and will come to a mobmov showing, and all those that venture out to create one of their own - you are my inspiration!