Chromogenic Magnification
Image Structure
A microscopic view shows that the image is made up of dye clouds. Chromogenic prints consist of three superimposed silver gelatin emulsions, each sensitive to an additive color (red, green, blue) with corresponding chromogenic dye couplers incorporated into each emulsion layer. When the positive silver image is developed, the dye couplers form dye clouds in direct proportion to the silver present in the image. The silver is bleached out and all that remains are three superimposed gelatin layers containing dye in the form of very small dye clouds.
A microscopic view shows that the image is made up of dye clouds. Chromogenic prints consist of three superimposed silver gelatin emulsions, each sensitive to an additive color (red, green, blue) with corresponding chromogenic dye couplers incorporated into each emulsion layer. When the positive silver image is developed, the dye couplers form dye clouds in direct proportion to the silver present in the image. The silver is bleached out and all that remains are three superimposed gelatin layers containing dye in the form of very small dye clouds.
What to look for: Under low magnification the image will appear as continuous in tone. Higher magnification reveals the image is made up of small clouds of color. Depending on the level of magnification and the image grain, they may appear as small pin prick sized dots of color, or be very distinguishable as clouds of color.
With 10x magnification the image will appear continuous in tone.
Under 30x magnification the image structure will begin to become visible.
Dye clouds are visible with 50x magnification.
Layer Structure
Fiber-based chromogenic prints are three layers: a paper base, a thick smooth baryta layer, and emulsion layers. Resin coated prints have a multi-layered support consisting of paper sandwiched between extruded polyethylene and emulsion layers.
Fiber-based chromogenic prints are three layers: a paper base, a thick smooth baryta layer, and emulsion layers. Resin coated prints have a multi-layered support consisting of paper sandwiched between extruded polyethylene and emulsion layers.
What to look for: Fiber-based prints have a thick baryta, paper fibers are completely obscured. Resin coated prints have a thick layer of pigmented polyethylene below the emulsion obscuring the paper fibers.
Fiber-based prints have a three-layer structure. With raking light and 50x magnification the paper fibers are completely obscured.
Resin coated papers have a multilayer structure. The paper support is sandwiched between clear polyethylene on the back and pigmented polyethylene on top. With raking light and 50x magnification the paper fibers are completely obscured.
Kodachrome and Ansco Printon have multiple layers with a pigmented acetate support. With raking light and 50x magnification the surface will be smooth.