In the early 1880’s many printers began adopting photomechanical means to transfer photographs to printing plates. This was especially true after the halftone process was refined in 1887 and made photo reproduction cheep to use. The problem that remained was that there was no color photography to base color separations on. A partial solution was found by creating a hybrid that would use a single photographic halftone in the same way as the linear key drawing that held the dots of a chromolithograph together, but here the color pallet would be reduced to a few hand drawn tints. The use of only one halftone also avoided possible problems with interference patterns that could occur when regimented patterns overlapped. Since these color plates were created by hand, there were many variations to how these postcards look. Even pallets could vary for while most printers reduced the colors used to the basic primaries, there was no consensus at this time as to which colors were primary. While these hybrid cards were not as impressive as those printed with ten or more colors the results were often more than adequate considering the cost saved. The entire printing industry would quickly begin shifting toward this new efficient model, which remained in use until replaced by process printing in the 1930’s. This process was used with both lithography and line block, and sometimes gravure.
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