High Key Photograph
The guitar photograph is referred to as high key because the dominant tones fall in the highlight-to-midtone portion of the tone scale.
For this image to be reproduced accurately with enough tone compression for offset lithography, the midtone placement must be shifted toward the highlight end of the tonal scale so that there is sufficient contrast to differentiate one light hue from another.
Small shifts in tone balance resulting from a printer’s effort to match the more saturated midtone hues are easily detected in the neutral whites and light grays, such as the top reflective surface of the guitar.
White, off-white, and metallic hues were chosen for this image because of the difficulty in maintaining color purity without introducing unwanted color casts.
