One way of supporting shadow exposure and not have the highlights be so severely affected is to do a double exposure of the film. The first exposure would be done through a diffusion material (such as opaque acrylic panel) at a zone III exposure. This would be determined by metering through the diffusion material. This would then be followed by the second exposure that would be indicated by the scene brightness.

The effects of this can best be described by the effects of the following example:

1. Assign a numerical value of 1 to Zone I, assign a numerical value of 2 to Zone II, assign a numerical value of 4 to Zone III, assign a value of 8 to Zone IV...since each zone of luminance is a doubling of light value, the numerical value of Zone VIII would be 128.

2. The Zone III pre-exposure would effectively raise Zone I luminance in the second exposure to a Zone III 1/3 negative density, it would raise a Zone II luminance in the second exposure to a Zone III 2/3 negative density, it would raise a Zone III luminance in the second exposure to a Zone IV negative density, and it would have a minimal addition to a Zone VIII second exposure (4 units of light added to a 128 Zone VIII value). This may take the scene out of the reciprocity consideration (for long exposure, depending on the film)...additionally it would allow the highlight values to be kept within manageable negative density.

3. Lets assume that we have a scene which has a brightness ratio of 15 zones. By exposing the first exposure at a Zone III pre-exposure and followed by placing the deepest shadows in the second exposure at a Zone IV placement (effective Zone IV 1/3 considering the pre-exposure), we will have contracted the actual density as recorded on the film to 10 2/3 Zones. While this is still not optimum, it is certainly much more manageable at the printing stage.

3. Additional to the halation consideration that others have mentioned, the other aspect is one of lens flare. It is vitally important to have the lens absolutely clean and multicoated. Any haze or film on any of the glass surfaces will cause the light to scatter (especially in the example addressed). The place that it will scatter is to the emulsion of the film.