Make this day on your calendar... Austin and I agree on something! ;-) Art
Austin Franklin wrote: > Bob, > > >>Enlargers can have interchangeable diffuse light sources and >>parallel light >>sources. The former give soft images with less contrast, while the latter >>give sharper images with higher contrast. >> > > That's absolutely NOT true. You do NOT get softer images with less contrast > from a diffuse (typically called "cold") light source. > > There has always been a controversy about the merits of > cold-lights. Careful tests have proven that exactly the same tonal > rendition can be attained with either a cold-light or a conventional > condenser when the contrasts of the film/paper are adjusted to match. > > The contrast difference between condenser and diffusion sources is > due to "Callier" effect which is scattering of light by the grains of > the film. The thinner the emulsion and the finer the grain, the less > Callier effect there is. For color film, where the image is composed > of very small dye particles, there is practically no difference between > them. The diffused source will tend to show blemishes less so is > commonly used for color printing. > > Personally, I believe cold light heads give better tonality for B&W chemical > darkroom printing, having spend some 25+ years printing fine art B&W > prints... > > Austin > > > ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body