A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Obscene Publication Act of 1857
The Obscene Publication Act of 1857 was a law enacted in England to keep printed material that might corrupt weak minds out of the hands of those open to immoral influences, and to deny contraceptive information to the working class. Donald McGill, a well known illustrator of saucy postcards, was prosecuted under this law in 1954. His conviction caused many postcard distributors to destroy their inventory and manufacturers to cease production of this genre out of fear of prosecution. Government agents, with the help of local watch committees, were assigned to seaside resorts in order to confiscate indecent postcards.

Octochrome
An Octochrome is a trade name for a type of postcard distributed by the American News Company that was printed using four-color continuous tone lithography. These cards are characterized by a sharp look with hard clean colors that emphasize blues and reds. They were printed in Germany.

Offset Lithography
Offset lithography is a printing process in which an image is transferred (offset) from one surface to another by indirect means. The general principals involved are identical to traditional metal plate lithography; the difference between them is in the manner they are printed. Various offset printing presses may have different roller systems but all share three major components; a plate cylinder that holds the printing plate, a blanket cylinder wrapped in rubber that carries the image to be transferred, and the impression cylinder which applies the pressure to print the image. A processed litho-plate containing an image is mounted on a cylinder, mechanically dampened with a wetting agent, and then rolled with ink. The oily ink is repelled from the damp areas and is attracted to the dry image areas. A blanket cylinder is then rolled over it, picking up the inky image onto its soft rubber surface. Paper then passed between this blanket cylinder and the impression cylinder, which presses all three surfaces together, transferring the image to the paper. If a web press is used, an additional roller system will cut the paper. By using an intermediate soft roller to transfer the image, the delicate metal litho-plate suffers less abrasion and can be used for a longer period before wearing out. The soft roller can also pick up and deposit ink better than a hard surface, creating impressions with greater fidelity. This process was discovered by accident in 1900 by Ira A. Rubel. Shortly afterwards Charles Harris invented the first Rotary Offset Press. This process was not widely used for commercial printing until the 1950’s when an easy to use, storable, photosensitive metal litho-plate was developed.

Off Register
When at least one color of an image printed from multiple substrates has its superimposition out of alignment with the rest of the image it is called being off register. These types of mistakes were not rare and usually decrease a postcard’s value rather than increase it as on stamps. Not all publishes were willing to loose money by discarding postcards because of quality control issues and most off registered cards wound up for sale.

Oilochrom
An Oilochrom is a trade name used by the publisher J. Salmon on some of his artist signed cards that reproduced oil paintings. These cards closely resemble the Oilettes issued by Raphael Tuck & Sons.

Oilette
An oilette is a term used by Raphael Tuck & Sons in referring to their postcard series that reproduced scenes copied from specially commissioned paintings rather than photographs. The first Oilettes were similar in style to their early chromolithographs that captured recognizable views, only they were printed with halftones copied onto printing plates by photochemical means. The later issues in this series tended to hold more generic imagery with an embossed textured surface added to simulate the brush strokes of paintings. These simulated strokes, sometimes referred to as oilfasism did not correspond to those of the painting but were added for simple decorative effect.

Optical Blending
Optical blending is the process by which the eye perceives a single color that is actually a mixture of two or more different reflective colors. If Magenta is printed on a page in small dots leaving white paper showing, both will reflect back to the eye as pink. If the correct balance of yellow dots are interspersed within it, the color will then appear as orange.

Optical Brighteners
Optical brighteners are chemicals similar to dyes that absorb high energy light in the violet and ultraviolet wavelengths of the electromagnetic spectrum and reflect it back out as blue light. A surface treated with an optical brightener emits more visible light than shines on to it, making it appear brighter. This increase in blue wavelengths also creates a whitening effect by making materials look less yellow. Brighteners are used in a variety of paper types including modern photo papers.

Optical Tones
Optical tones are the different values of gray as perceived by the eye when looking at a series of different sized markings, usually dots, of one single value. When the individual marks fall beneath the size where they can be perceived by the naked eye they take on the illusion of a solid tone. By varying the proportions between the printed dark ink marks and a lighter backdrop an entire optical tonal range from black to white can be simulated in either subtle transitions or solid hard edged shapes. Most optical tones are derived from the employment of line screens during the reproduction process to create halftones.

Oranograph
See Uranograph

Orientalism
Orientalism is an exotic mannerism by which the people, culture, and land from the Levant have been represented in Western culture. This approach was widely employed in the arts and literature in the later half of 19th century. As Islam spread beyond the Arabian peninsular so did the definition of the Orient to include all Muslim lands. The Russian seizure of Central Asia, Austria’s dominance of the Balkans, France’s move into North Africa, and the British conquest of Egypt provided greater access to these places for both European and American artists. In their ever increasing efforts to generate sales, artists began to travel to Muslim lands in search of new themes; and cultural differences, whether real or imagined needed to be stressed in order to present something unique. In depicting a foreign culture artists also had license to paint topics that were totally unacceptable to express in a Western context. While Orientalist painting was often overtly erotic in nature, it was also used to present a more fanciful exotic setting for illustration and advertising. No one style dominated this art movement; its cohesiveness was derived from a limited geography. Orientalism has additional meanings when applied to writing or cultural studies. It can be said that the concept of Orientalism created a false image of the Muslim world in order to rationalize European exploitation. While the arts may have reinforced these ideas, they did not share the same goals; Orientalism in the arts was largely used as a marketing ploy to increase sales, and whether a falsehood or not it provided the inspiration for new types of imagery in the fine and graphic arts.

Orotone (Goldtone)
An Orotone is a positive photographic image placed onto a glass plate with a metallic backing. They may have been made by contact printing one glass negative to another. The image is exposed to a photosensitive silver emulsion in a collodion or gelatin base. Afterwards the back of the glass plate is coated with a mixture of bronze (copper and zinc) in an oil base, to give the image a golden luminous effect. These images were sold framed due to the fragile nature of glass and the painted back that is easily scratched. This uniquely American process is sometimes called Curt-tone after its first practitioner Edward S. Curtis.

Orthochromatic
A film or photo paper that is sensitive to all wavelengths of the visual spectrum except red is referred to as being orthochromatic. This allows it to be processed under red safety lights despite its fast speed. Today orthochromatic film is sometimes used in graphic work with process cameras. It was invented by Herman Vogel in 1873.

Overprint
An overprint is information or an image printed onto a card that was never part of its original design. Overprints were sometimes used with or without strikethroughs to make corrections in a cards title. Overprints might be needed to correct a mistake in printing or to recognize a change in place name. Most often overprints were used to add advertising or holiday greetings to a card. Instead of going through the expense of designing a whole new postcard for a product, a card with an image already on it would be found and a small advertisement would be place on its front or back (not to be confused with stock cards). Overprints were usually in one color so they were easy to print on a hand press without fears of bad registration. While some advertisers found imagery to match their product, other printed over cards in an arbitrary fashion.

Overrun
An overrun refers to the excess printed material manufactured above the original order. This often occurs when more acceptable prints are made above the margin allocated to be lost due to error. Overruns can also occur when small and large orders are printed at the same time off of the same plate. The cost in paper and ink are far less that the cost of labor in resetting a press for a new job. The excess prints might be added to the customers order for free or sometimes used by the printer to advertise examples his workmanship.