Tuesday, September 4, 2012

Reflective scan is better

Once upon a time mankind invented lens and optical devices, cameras, projectors, glasses, etc.. The first photos were made on opaque surfaces (daguerreotypes for instance) and only many years latter the transparencies were introduced, first in glass and then acetate and polyester like today we still use.

I don't intend to tell here exact historical events, but only remember that the first photos were made in opaque surfaces. Daguerreotypes made with a good lens are extremely sharp because the surface is completely flat, no roughness like in the paper and also because there is no other image transfer like the transfer we do from a transparent negative to a paper copy. In this transfer we have noise introduced by the grain of the film, the lens of the enlarger and our evaluation of sharpeness, the roughness and grain of the paper, etc.. The final result can not be compared with the sharpness of a daguerreotype, for instance. Daguerreotypes didn't survive because the new processes with negatives was cheaper, reproductible and the image was not mirrored like in the daguerreotypes.

Now, with the revival of old processes, many of us are still using transparencies instead of an opaque medium, but the transparent material, films or sheets, have to be scanned instead of beeing enlarged optically. Doesn't make sense for me. If we want to get better pictures, we are introducing noise unecessarily when scanning at transparency.

With the monobath I am using, Parodinal-salt, I obtain pictures on film that can be scanned directly and reflective. Because the image seen from the emulsion side is sharper and will be closer to the scanner optic, an image scanned reflective is much more sharp than the same image scanned at transparency.

This means that manufacturers should consider the possibility of making opaque films instead of transparencies, even on paper instead of acetate or polyester. This paper negative (or positive) could then be scanned by every normal scanner instead of the expensive photoscanners. People using Harman positive paper (very expensive) with their Pinholes are in the right side, I think. But why not direct reflective scannable films?

Scanned at transparency

Scanned reflective

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