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Hi Fe A, Print Film vs. Slide Film: When it comes to viewing pictures, noting beats slide film projected via excellent projector onto a quality screen. This combination yields the greatest dynamic range. The secret is in the viewing. We view slides by transmitted light. Light from the projector transverse the dyes residing on the slide. As the light makes this passage, the dyes act as filters, allowing some colors to pass while blocking others. In this application using projected light the image on the screen is breathtaking because the light makes one transit through the dyes, the dynamic range of the color slide is greater than 256:1. Additionally, since the observer is generally seated in a darkened room, the slide-on-screen overshadows all. This view causes the human eye/brain to auto correct for color balance. This is the most impressive photographic presentation possible. When it comes to correctness of color, the negative film is supreme. Since the negative is never viewed by the audience, additional corrective measures can be built into the film. All color negative film incorporates two auto masks. This gives the film its customary orange color. Their purpose is to correct defects in the cyan dye and the magenta dye. Photo science has yet to make these two dyes in the correct strength and with the correct color. Cyan must be the exact opposite of the primary red and magenta must be the exact opposite of the primary green. The third, yellow dye is correctly positioned and is the exact opposite of the primary blue. To the casual observer the orange hue of the color negative is assumed to be a uniform base color however it is in fact this is two developed-up positive images superimposed on top of the three negative dye images. Some specialized negative films are even more complex. This advanced technology gives the color negative the advantage. The fact that the color negative must be printed or scanned for final viewing supplies an additional opportunity. The printing/scanning cycle can be thought of as a second corrective taking of the picture. Only this time, corrective measures are employed. The color and the intensity of the printing light is custom altered for each frame. This technology significantly improve the fidelity of the final image. Both the slide and the color negative have a dynamic range of 256:1 however, when either is printed on paper, the print is viewed by light that must transverse the dyes on the print paper. The path is viewing light, transverses the print dyes, strikes the white undercoat, reflects backward, makes a second transit through the dyes, this light is now observed by the viewer. This two dye transit path lowers the dynamic range of a print on paper to 64:1 or less. So which is best? Likely an argument will ensue. However, from a technical standpoint, color negative materials blow away all rivals when it comes to transferring images onto paper. However some like colors exaggerate with high contrast and vividness. For these folks, color slides printed on paper are unsurpassed. Me, I will take the color negative root. I must add, I think in the not to distant future, film will be mostly found at the museum right nest to civil war medical instruments. Read my lips – Go Digital. Alan Marcus (marginal technical gobbledygook)
alanmaxinemarcus@att.net
September 13, 2008
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