This was shot after my battery died and took my exposure meter with it. At this point I was experimenting with f/16 and f/8 apertures and 1/30-1/125 shutter speed at 90 and 100mm on my Sigma 70-300mm zoom.

The orchids hung heavy with their abundance in front of a dark blue backdrop. By zooming in on the flowers to get a light reading, and then zooming out, double checking the exposure difference, and underexposing the shot by a stop to a stop and a half, it becomes simple and easy to isolate the blooms against their background.

The exposure variance when underexposing will differ from camera to camera, film to film (though the differences between these, excluding changes in ISO, will be relatively small). The key behind every simple and difficult technique is to know how YOUR camera and equipment will react to the situation. And, naturally, bracketing greatly increases your chances of getting the image in your mind onto the film.