Just to add to this, since I do many Polaroid manipulations, there can be a variation that might work to get around some frustrations. If you find like I did that rubbing the emulsion off the backing resulted too often in breaking the emulsion, then try this variation:
- Get the water to a slightly hotter than usual method (be careful, since you will not be able to put your fingers into the receptor)
- Toss you Polaroid into the hot water in the pan/receptor, making sure it is completely submerged
- Use a wooden stick to move the Polaroid around a bit, or just stir the hot water slightly a few times
- Then the variation is to leave the Polaroid in the hot water, until the water cools quite a bit; when this happens, often the emulsion will simply float off the backing . . . in other words, no rubbing the emulsion off the backing. Obviously, nothing is perfect, so you might find a corner still sticking to the backing, though some people I have taught this hotter water method find it slightly easier.
Things to consider: the hotter water has a tendency to cook out darker colour areas on 669 film, so the shadow areas of your image might be slightly lighter than if you used the hot water to cooler water method. If you get the water way too hot (like boiling), you might actually cook the emulsion and severly bubble the Polaroid.
This hotter water variation happened to me by accident. After a slightly frustrating time destroying Polaroids, I ended up heating the tea kettle to whistling. Then I poured the steamy hot water into a baking dish, and chucked a Polaroid into it. Almost immediately at that point I got a phone call. Five minutes later, when the phone call ended, I walked back into the kitchen, to see the emulsion floating in the water, with the backing paper detatched. I let the water cool a bit more so I could get my fingers into it, retrieved and disposed the backing paper, then transferred to acetate and to my art paper.
Another note to add to this is that you can get whiter or sometimes brighter results on your final transfer to paper by rinsing with white vinegar. Not everyone likes the smell of that, and the effect is subtle, but effective.
A G Studio