Re: Bierstadt patented in cover book stereo viewer


robert mcafee
 

Correction Harroun & Bierstadt  patent (not Harround.)

Note Edward Bierstadt invented this improved stereoviewer integral to the book and Albert Bierstadt the painter was his brother.  Both made stereo images

American portrait and landscape photographer, and engraver. He was a brother of the painter Albert Bierstadt, and made a number of engravings of his brother's work. He opened his own studio in New York City in 1860. He also held an 1876 patent for an improvement to the Stereoscope Viewer, used for the extensive body of stereographs created by the Bierstadt brothers.

He was hired by William West Durant to take a series of photos for an advertising brochure entitled The Adirondacks, Artotype Views Among the Mountains and Lakes of the North Woods to publicize Blue Mountain Lake and Raquette Lake in the Adirondacks.

Much of his work is simply signed "E. Bierstadt NYC."


Some information on the Artotype "The Artotype is a form of collotype, a photomechanical printing process from a gelatin surface, that was available at Bierstadt's Artotype Atelier in New York.

Info below from site MetroPostcard Guide to Postcard Printing Techniques 2 .  Some enlarged images to be seen at this link (for Art Clark's question)

COLLOTYPE
The collotype is a continuous tone printing process first patented in France by Alphonse Louis Poitevin in 1855 under the name Phototypie. It began to be used commercially as the Albertotype in 1868 after Josef Albert in Germany perfected the method, but when patented in the United States one year later it was given the name Artotype. The technique begins with a greyed glass plate coated with a photosensitive dichromate colloid gelatin that puckers and cracks as it dries. When exposed to light through a reverse negative, the lit areas harden into an insoluble nonabsorbent finish. It is the areas within the reticulated cracks that harden the most because they are the thinnest part of the emulsion. They in turn will print the darkest in proportion to the tones of the original image. The dichromate emulsion in areas with little or no exposure to light remains soluble and is washed out from the gelatin with cold water. The plate is then printed in a similar manner to a lithograph. A solution of glycerin and water is spread over the plate's surface, which is absorbed by the remaining gelatin. Areas that are to carry the dark tones absorb little or no moisture while areas for the lighter tones and non-image areas absorb the most. When greasy ink is rolled over the gelatin on the plate, the non-image areas holding the most moisture repel the ink, and the dry hardened image areas attract the ink. Once printed the reticulated pattern creates a continuous toned image of incredible detail for which it is prized.

During the 19th century the collotype process was best known as Artotype, the name given to it by Josef Albert. Many others however elaborated on the process and trade names such as Hoeschotype, Inkphot, Paynetype, Photopane, Photo-type, and Albertype abounded. Some became more widely used than others and a number of different variations on this method were used to produce postcards. In 1868 the German Max Gemoser developed an important variation, which became known as Lichtdruck. The gelatin skin was removed from his processed plates and remounted onto litho-stones for greater support during printing. Despite certain shared characteristics, collotypes are not always easy to identify do to natural variations in the drying gelatin and numerous trade secrets. With no set standard the most uncommon collotype patterns may be difficult to distinguish from photogravure.
Collotype: The fine grain of collotypes with their white centers have a barnacle like look since the ink prints from the reticulated surface the plate. Though similar to the grain of aquatint and variable in size, the wormy look caused by the gelatin curdles is usually a dead giveaway in identifying the technique. This however can only be observed under extreme magnification as the close and closer details below of the postcard above demonstrate.
The greyed glass plate used to make collotypes was a major drawback for the process; it is very fragile and its shallow gelatin surface can rarely yield more than 500 impressions. Some have claimed to have pulled 2000 images from a single collotype plate but this may be an exaggeration. For large orders a new substrate would often have to be prepared substantially adding to the cost. Gelatin plates did not age well due to their organic nature and could not be stored for long periods to print at a later date. They were routinely scraped down after printing so that the glass could be reused. This severely limited the commercial applications of this process, but it proved adequate for small press runs and was widely used in postcard production. Glass was used as a substrate because it was one of the few materials that gelatin would adhere to in a thin even coat, but after August Albert discovered a way to mount a collotype emulsion onto an aluminum plate in 1896, this medium became easier to use and was finally adapted to the rotary press. Glass plates were still preferred by some printers who continued to use them into the 1960’s. Even when working with metal plates, the delicate gelatin emulsion still needed to be treated more carefully than other substrates, which slowed down production time. Even factors such as high humidity could severely limit their production; and they were usually printed in places where the weather was more stable. Despite all these drawbacks, collotype was still used to produce more black & white postcards than any other technique.
There were no special presses built to print collotypes, perhaps due to all the secrecy that surrounded this process. The image is usually transferred to paper on a modified lithography press or sometimes on a flatbed cylinder press. Its use in commercial printing greatly expanded after 1873 when a way was found to print collotypes with steam powered presses. Though it still remains the most accurate reproductive printing method available today, the process was largely abandoned in the 1990’s in favor of high resolution digital technologies. An order placed for real photo postcards in the early 20th century might be filled with printed collotypes nearly half the time because the resulting images were so similar that the two methods were generally considered interchangeable.


Join main@Photo-3d.groups.io to automatically receive all group messages.