Silverbased

Lately I’ve been telling everyone I talk to about my newfound, bittersweet fascination with Polaroids. It’s like learning that a loved one has a terminal illness—you want to savor as much of your remaining time together as you can.

As I understand it, the factory production lines for Polaroid film have actually stopped; what’s left is a few months’ supply still in the distribution pipeline. So I’ve been buying up Polaroid 600 packs whenever I come across them. (The best prices I’ve found are at Office Depot online; and locally—brrrr—at Walmart.)

But to stretch those last remaining shots, what better idea than to expose each frame more than once?

Most of the peel-apart packfilm cameras allow double exposures easily; and there is a known technique to trick Spectra cameras into shooting them. But for 600 film cameras, the only method I have learned about seemed complex and inconvenient.

But today I have a nifty camera mod which permits double exposures on 600 film—an inspired idea by my friend Allison Stanley. She owns a well-used Polaroid One600 camera, which sometimes failed to eject prints correctly. Appreciating the quirky beauty of her overlapping exposures, she suggested wiring in a “kill switch” to disable the print-eject motor at will.

I thought that idea was pure genius, and immediately wanted to try it out. It turns out that there’s a slight complication: All the 600 cameras I experimented with use the feed motor to recock the shutter too. But still, after adding the switch, a workable technique for 600-film double exposures does become possible.

Opening Up the Camera

The Polaroid One Step shown here is a typical 600 film model—easy to find for a few dollars at the thrift store etc. And this gray body-style with its flip-up flash is particularly easy to open: Its plastic shell simply snaps together. Let’s look.

Start by taking the flip-up flash and holding at about a 45-degree angle as shown. At this angle, it is possible to gently flex the side ears of the flash outwards and pop them free from the the camera body.

Lay the flash back on the top of the camera, out of the way as you remove the front panel. (But try not to put too much strain on that delicate ribbon cable as you go through the following steps.)

The front of the camera simply snaps into place; carefully insert a prying tool at the points shown by my knife and the red arrow; then ease the camera faceplate free. (The shutter button parts will fall out loose, so work over a towel or a tray so nothing gets lost.)

Here’s the opened camera, with the shutter-button assembly at left and the removed front panel at right.

Locate the ribbon cable which connects to the motor at the front of the camera. The conductors I’m pointing to are the ones that provide electricity to the motor. All we need to do is to cut through one wire and route it through an external switch, and the camera’s film-eject motor can be disabled as desired.

One flaw of that gray One Step above is that its electronic flash fires with every shot. Especially for double-exposures, I preferred not to risk washed-out colors by always using flash; instead I made the kill-switch mod to a vintage “rainbow” OneStep600 instead. But its disassembly needs a few extra steps. If you want to modify one of these, see the details here, then return for the other steps below.

Make the Hack

With small scissors cut through one of the conductors of the ribbon cable (the left side gives you more length of wire to work with). Then slice the clear plastic between conductors so you can pull the free cut ends outwards.

Prepare a small switch by soldering about 3 inches of wire to it. The type of switch isn’t important; but for ease of remembering I’d suggest orienting it so the contacts close when the switch is moved towards the front of the camera.

Drill a small hole in the side of the camera, into the hollow space under the photocell assembly. Thread the switch wires through this hole. Be sure to locate the hole far enough back so that the camera’s front panel can be replaced without interfering.

You could do a neater job than I did by mounting the switch inside the camera body; but I actually preferred mounting it in a sideways orientation where it would be less likely to get snagged and flipped accidentally. I glued the switch into place with hot-melt glue, adding an extra blob on the bottom to cover and insulate the solder tabs.

Cut back any excess length of the two wires, and solder their ends to the cut motor ribbon cable. The ribbon seems to be tinned already, so I found soldering to it surprisingly easy; but you do need to avoid jiggling the wires while the molten solder cools. (Forceps, etc. could be useful here to hold wires steady.)

That’s it!

Now it’s time to put the camera’s front back on. Be sure the lighter/darker control is centered so it will engage with the internal slider properly. I think it’s easiest to reinstall the shutter button parts by tucking them into the recess on the camera’s front, then sliding all the parts back into place as a unit:

Re-attach the flash pivots (again holding it at a 45° angle) and the camera is ready to use.

Using the Modded Camera

Okay, we’ll assume you’ve wired the switch so that when flipped forwards, the contacts are closed. In this position the camera operates exactly as originally.

Keep the switch “on,” and load a fresh film pack. When you close the door, the black cover sheet should eject. (If it doesn’t, something is wrong: Re-check your work.)

Remember, after every exposure the motor needs to run sometime, to re-cock the shutter and prepare for the next shot. But the switch allows us to delay that, and not have the print spit out immediately.

So the technique for double exposures is this:

• Flip the switch backwards, and make your first exposure (shutter fires, but print does not eject). I’d suggest that you slide the lighter-darker control all the way to darker for your first tests.

• Drop the film door open; then flip the switch forward (the motor immediately runs; but the rollers are disengaged so the print stays inside the pack)

• The front edge of the print (or as shown here, two prints) is pushed out of the pack slightly. Carefully push these front edges back into the film pack, as far as you are able.

• Close the door, leave the switch forward, and make your second exposure (print ejects normally).

• A third exposure (etc.) is possible by repeating the same cycle:

Switch off/shoot/drop door/switch on/tuck print into pack/close door.

There’s a couple things to note about this method. One is that pushing the front edge of the print back into the pack in daylight can leak light into the pack: This gives the funny “row of teeth” pattern seen at the bottom of this shot:

You can minimize this, by delaying the door-drop maneuver until you can move into dim light (or, push the print edge back into the pack by feel, with a jacket etc. thrown over the camera). But I’ve actually grown rather fond of this quirk.

The other issue is a general one for double-exposures: You can only add light, not subtract it. Any brightly-lit area of your subject tends to override the image in the other exposure. It’s mainly in the darker areas of the scene where you’ll see the double-ness of the exposure. So try to include sufficient dark, blank areas in your shots. And stick to simple, bold subjects until you get the hang of how images combine.

These are strange days, when the cost of a complete Polaroid camera is trivial compared to the preciousness of each exposure. Yet the freedom to cut up and re-jigger old cameras is liberating, too. And the magical serendipity of Polaroid doubles seems like a fine way to celebrate our farewell to this unique and irreplaceable medium.

Important Update: with most 600 cameras, making double-exposures will confuse the frame counter. After making 10 exposures (not after ejecting 10 prints) the shutter button will lock.

The slightly-inconvenient cure is this: grab a spare black film-pack cover sheet and go into a dark room. Open the camera, remove the film pack entirely, and slip the black sheet back into the top of the film pack. (Orient the little dangly plastic tag towards the cut-away corner of the pack.) Close the film door, and allow the camera to spit out the black sheet again (flip on the kill-switch if needed). The frame counter will be reset and you may continue taking pictures.

Sadly, we are all counting down the days now, until Polaroid stops making all their instant films.

I must confess that in the past, I rarely used Polaroid cameras, finding the “$1 per image” aspect a little daunting. But also, most of their plasticky, auto-exposure consumer models seemed rather lacking aesthetically. (I do make an exception for the SX-70 camera—which still seems as futuristic today as it did when it came out in 1972.)

But in the spirit of savoring our Polaroids while we still can, recently I bought some type 669 film packs.

These peel-apart films are an older technology than Polaroid’s “integral” types like 600 or SX-70 Time-Zero. But the peel-apart pack type was adopted for so many professional and technical uses that demand remained high until digital arrived. So there are several packfilm emulsion types still available. Even Fuji has now started making a line of compatible film packs.

I’m skeptical that another manufacturer will start up making Polaroid’s integral films: It’s a much more complex technology (each pack includes a unique flat PolaPulse battery). But it’s nice to feel I’ll have the Fuji backup option, if I end up falling deeply in love with my pack-film projects.

Anyway, as I mentioned, I was never that fond of Polaroid’s own cameras. This started me thinking about “alternative” ways I could expose images onto 669 film. So today I’ll show the first of two Polaroid camera hacks: The PackPola Pinhole.

This one is so ridiculously easy that it barely deserves the name “DIY project.” Here is the executive summary:

STEP 1: Find a Polaroid microscope camera
STEP 2: Tape an 0.4mm pinhole behind its dark slide
STEP 3: Take pinhole photos

But, oh all right—if you insist on making things more complicated, here are some additional details.

While most of the later pack film cameras were plastic-bodied, Polaroid did manufacture a stout cast-metal body which was used for certain products—in complete cameras, or as a dedicated Polaroid back for technical uses. The model shown (which I was told was a microscope camera) has a rigid cast-metal “pyramid” where a civilian Polaroid model would have bellows, with a custom attachment flange on the front.

Aside from the nice brushed-metal finish, this camera has two useful features. First, it has a real live tripod socket on the bottom (vital for long pinhole exposures). More importantly, its microscope fitting comes equipped with a dark-slide—we can reuse this without modification as the shutter for our pinhole camera. (I gather microscope photos must require long exposures too.)

Now you could build a Pola-pinhole by hacking a regular bellows style camera too—and these models are practically being given away today. You’d need to remove the front of the lens/shutter assembly, and attach a pinhole behind the bare lensboard. (See the excellent step-by-step disassembly photos here—also getting a chance to practice your Italian!) But in that case, you would need to improvise a shutter, and the focal length will be about 30mm longer (and hence less wide-angle-y) than with the microscope camera.

The pinhole is pierced in a thin sheet of metal—the sidewall of a beer or pop can is ideal—and taped inside the “pyramid” behind the shutter. This gives a focal length of about 74mm. (The diagonal of a packfilm image is about 120mm, so this yields a wide-angle coverage similar to a 28mm lens on 135 format.)

For that focal length, the optimum pinhole diameter is roughly 0.4mm or 0.015 inch. This equates to a pretty tiny f/stop: the nearest whole stop value is f/181. That’s 7 stops smaller than f/16—useful to know when trying to translate light-meter readings into pinhole exposure times.

Back up your pop-can metal against something firm like a phone book, then just barely pierce the metal with the tip of a sewing needle—don’t poke all the way through! Sand away any rough burr around the edge of the hole using fine 320 or 400 grit emery paper. Twirl the needle tip in the hole to smooth any raggedness—you want the hole to be nice and round.

You can measure the diameter of your pinhole exactly, by placing it on a flatbed scanner and scanning at the highest possible resolution. Knowing the exact DPI of the scan, and reading off the dimensions of a selection just including the hole, you can see if its diameter is in the right ballpark.

I often start with a bunch of metal blanks of 50mm square, a size that will fit inside a cardboard 35mm slide mount. By setting up a slide projector at a known magnification, I can quickly go back and forth between checking sizes and roundness and gently enlarging holes with the needle to reach the desired diameter.

Of course, one great advantage of a Polaroid pinhole is that you can just wing it. Try an exposure at what you think your equivalent f/stop is. If it’s too light or too dark—next time use a revised guesstimate of your f/number when you figure the exposure.

Polaroid 669 is well-known for “interesting” color shifts when developed in cold temperatures; but also when using the kinds of longer exposure times needed for pinhole work. With a multi-second-long exposure under open sky light, you can have quite a strong blue/cyan cast:

You might enjoy this effect—or, you can tape a warming filter in front of the pinhole.

In direct sun, start by trying one of the #81 series filters. But for longer exposures or in cooler light you may need a stronger orange/salmon colored filter, like one of the #85 series. If you can get your hands on a swatch-book for theatrical gels (like Roscolux), that would offer a huge range of colors to try (with pinhole work, you’re not exactly worried about the optical flatness of the sheets).

Personally, I raided my cache of oddball Series VI filters, and found a perfect Harrison brand color-correction filter, designated “C3.” This filter loses a little less than one stop of light; I used exposures of about 3 seconds in full sun, up to 30 seconds in darker shade. The color palette of 669 seems to give a nice pastel softness, thought without much saturation in the reds & yellows.

If you have never used pack film before, you may be flummoxed by the profusion of weird tabs that sprout from the end of the camera (from a slot helpfully labeled “4″). This becomes easier to explain when you understand that pack film is actually negative and positive sheets stored separately, which need to be sandwiched together to start development.

The first black tab pulls a light shield out of the way, and uncovers the top negative sheet. After you make an exposure, pulling a white tab slides the exposed negative around into contact with the positive print paper. However both are still dry at this point, and nothing happens yet.

Pulling out the wide arrowed tab bursts a pod of chemical paste, and the two chrome rollers smoosh a uniform layer of this goo between the positive and negative, starting development. After 60 seconds, the image is fully transferred and you can peel the print away. It stays a little tacky for a few moments, so don’t accidentally get it stuck to another print.

I discovered pretty quickly that my microscope camera pack-holder had a couple of quirks—possibly the reason why it had been retired and discarded in the first place. The first is that its rollers seemed to have gotten tired, and weren’t spreading the developer goo all the way to the far edge of the print. But actually, the white blobs caused by this were one of those serendipitous creative accidents that I ended up liking.

The other issue was that there was a serious light leak somewhere in the camera body. Now, remember that a pinhole (like a lens) forms its image upside-down. So this radiant splash of light at the bottom of the print was coming from somewhere on the top of the camera.

Eventually I realized there was a tiny gap at the seam where the pyramid cone attached to the film back—perhaps the camera had gotten dropped once. A bit of electrical tape fixed that up. But as light leaks go, this may be one of the more beautiful ones I’ve seen!