When paper or film is overexposed, a reversal of tones may result. A partly-developed print or negative that is taken out of the developer, exposed to the room light for an instant and then returned to the developer will result in an image like solarization #1, below.
To make a solarization, make a print or expose film as usual. (You may find, later, that some images look better if you underexpose or overexpose them a bit. It's all up to personal preference.) Develop for about 1/3 the normal time, or let the image come up about halfway, then drain or squeegee the paper or film, and put it on a flat surface, like the back of a tray. Re-expose it to the room light for a short instant. Make test prints and or use copy negatives (not your valuable original film) first and experiment as to exposure times, which can vary widely, depending upon how bright or how far away the light is, what kind of film or paper you are working with, the developer, and so on. High contrast paper seems to work well for solarizations. The enlarger light, without a negative in the carrier, may be used instead of the room light. For color solarizations, on color paper or film, use different color filters in the enlarger, or tape filters or gels, or even cellophane, over the room light, to get different colors on the final solarized image.
Some tips I've heard, but haven't tried:
Try using images with very light highlight areas right next to very dark shadow areas.
Put paper or film against a dark background for re-exposure (like black plastic from a film box, laid on a tray back).
Solarizing a halfway-done, too-light print is a good way to try to save it; what used to be a mistake in exposure could end up being one of your best prints.
Solarizations can be unpredictable. Fake solarizations and posterizations are ways to achieve similar effects consistently.
To make a fake solarization, make a high contrast positive and a high contrast negative of the original negative. Sandwich them together and contact print them onto another piece of high contrast film to make a "negative-positive negative" (sorry. a better term is needed) . Then sandwich the original negative with the negative-positive negative, and contact print that onto a piece of continuous tone film. The resulting print from the continuous tone negative looks like a solarization. Not all the above steps are necessary. A fake solarization can be made from printing a high contrast negative or positive sandwiched with the original negative, or from printing just the high contrast negative-positive sandwich, or from other combinations, depending on what the original looks like and what you want the final print to look like.
Posterizations can be complicated, but are gratifying to make. Here are some sketchy instructions. If you really want to do this, email me and I can give you more details.
For a posterization, you need to first make several negatives and positives of your original image in the size you want to print it (for example, make 8"x10" copies of a 35mm original, for a final 8"x10" print).
A posterization might have just one negative and one positive, or more. Each one or pair will be a different color or value, so the more negatives, the more colors.
The example below utilizes 3 negatives and 3 positives:
Make 3 positives, for a highlight, mid tone, and shadow, and then contact print them to make 3 negatives.
Line all the negatives and positives up and mark them in some way for registration. Punching matching holes in all of them is a good way to do this.
Optional: Make little cuts in the top like those on film so you can identify each separate piece of film in the dark (i.e. cut a tiny piece off the right corner of your highlight negative, then a tiny corner and a tiny notch next to it for the middle negative, and so on.)
Each negative or positive or pair of negatives will be a different color, and filter pack. To figure colors for filter packs, read color swatches with a densitometer and make some test strips of the color readings at different exposures, and then use those for your posterization exposures.
Put registration pins right next to or on the easel, under the enlarger, and tape things down so they don't get moved in the dark. Or find an easel that already has registration pins. Or use a tape registration system, lining up the paper and negatives with tape or taped-down cardboard markers.
First, make test strips of all your negatives and colors, to determine times and narrow down color choices. If you are doing the second method, make test strips of combinations of the colors to determine in-between colors that occur where blank areas on negatives overlap.
For the final print, place color paper in the easel.
Check the notches to identify negatives as you go along. Expose each negative or negative-positive pair with the filter packs you figured out beforehand.
First expose the shadow negative,
then expose the shadow positive plus mid-tone negative in register (tape together beforehand or use registration pins),
then expose the mid-tone positive and highlight negative in register,
then expose the highlight positive,
all without moving the paper.
Then process the paper as usual, according to manufacturer's instructions.
Another way to do this is to
lay one negative at a time over the paper for an exposure, checking the notches to identify them.
Expose each negative/positive with a different filter pack, which you have figured out beforehand, without moving the paper.
When all are exposed, process the paper as usual.
This way you will get in-between colors where the blank areas on the negatives overlap.
Either way, it helps to plan ahead carefully, lay things out in order, tape things together, so you don't get mixed up in the dark.
Nowadays you can do all this on the computer with a couple of mouse clicks, but you don't get that tremendous sense of accomplishment that many hours of fumbling around in the dark and sloshing in chemicals can give you.
done by just holding up the print to the light. The black areas were the image that had already come up.
made from a positive and negative, of an original 2 1/4 negative, sandwiched together and contacted onto another piece of high contrast film. The resulting negative-positive negative was then sandwiched with the original negative and contacted onto Tri-X sheet film. Then that negative was printed to make this image.
from a high contrast positive/negative sandwich from a black and white negative; contacted onto continuous tone film. The negative in the sandwich was slightly fogged, resulting in solarization.
a fake solarization of sorts
Fake solarization - type image
using some of the same negatives and positives made for the color posterization, printed on black and white paper. Note tape and registration holes.
Edge of a color solarization,
showing finger mark where paper was held during re-exposure, and solarized margins. Room light was tungsten. The print is from a black and white negative of tree roots, printed on color paper. The image was a warm gray and white, and after re-exposure, the background turned orange, the highlights turned dark blue and the margins turned magenta.