I noticed recently that even my recent PX70 shots were shifting to blue and losing all the vibrant colour. This is disappointing but not entirely unexpected – Impossible state that this is what happens if the film is left alone. I had tried to use some of the techniques they publish to prevent the shift occurring by drying the film, but it seems the British atmosphere is a bit too damp to keep these films in good condition.
The one technique I hadn’t used which they more or less guarantee to stop the shift was to peel the two halves of the film apart. The idea being that once separated from the backing the emulsion dries much more easily, and no further reaction occurs to shift the colour.
I did try it once with a PX70 “First Flush” shot, but found it difficult to get the peel started and that the emulsion tore badly. However, faced with having no recognisable colour in any PX70 photos I figured it was worth trying again, and even going a step further and trying an emulsion lift – removing the image-bearing emulsion from the film completely and transferring it to another medium. In some ways this is a high risk procedure as, once you start peeling, there’s no going back and you could lose the only version of the photograph you have. Since I always scan each frame a few hours after taking them and since the PX70 fades anyway this is less of a problem for me.
On the upside lifting the emulsion and transferring to another medium, opens up a new range of possibilities, since whatever colour and texture the new support has will combine with the transferred image. Also, since the emulsion is rendered very soft by the process it’s possible to distort and manipulate the original image.
After some trial and error I’ve settled on a reliable technique that allows me to separate the image from both the white backing sheet and the transparent front film more or less intact and transfer it onto a suitable new carrier – typically a sheet of watercolour paper. The poppy image at the start of this post is one of the earlier attempts, where some of the emulsion tore and couldn’t be saved. Since then I’ve figured a few ways to prevent this happening, so I thought I’d try and share them. As far as I can tell these methods are equally applicable to both colour and black and white materials, although I’ve mostly been using the monochrome PX600, as in the clematis photograph, since I ran out of PX70.
The first step is to peel apart the film and remove the backing sheet. In my experience this is easiest within the first few days after shooting. In this time the backing paper comes away easily as the emulsion is still moist. After this, as it dries it seems to stick more to the white backing and can tear when you peel it. You can get around this by heating the film first. I found that by floating a foil tray in a larger tray of hot water and placing the film inside for a minute or two, when the film began to curl it was ready to peel apart – the heat softens the emulsion so that the backing sheet separates without damage to the emulsion.
To do the actual peeling you need to either peel off all the white mylar foil covering the film, or at least cut through it in away that means the two halves of the film are no longer connected by it. You can do this either by running a scalpel blade along the edges or by cutting a millimetre wide strip of every edge with a sharp pair of scissors. Next cut or peel off the strip of black tape running down each edge on the back of the film – I find it easiest to just cut this with a scalpel at the top corners.
Now you should be able to grab one of the corners of the backing sheet and peel it away smoothly, leaving the emulsion attached to the clear front sheet, forming a positive transparency. There will probably be some of the white titanium dioxide from the backing sheet stuck to it, but that should get washed off during the next stage. If the emulsion sticks to the backing sheet while peeling, just keep pulling gently, so that it comes away. The resulting transparency may end up a little distorted or wrinkled, but again that can be fixed in the actual lifting stage.
Since I don’t want to turn this into a mega-post I’ll stop here for now, but in Part 2, I’ll describe how I separate the emulsion from the transparency and transfer to a new medium, and all the challenges that presents.