We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
400 XII. PEOCESSING AND EELEASE PEINTING
to notch one edge of the image-bearing film at a fixed distance relative to the place where the light change is to occur. In the printer, a small roller rides the edge of the film, and when it reaches a notch, it permits a snap-action, sensitive-pressure switch to close, effecting the light change. It is unfortunate for the owner of a film that there are standards neither for the dimensions of a film notch nor for its location relative to the printing aperture. A practical result of this lack of standards is that it is impossible for a film notched for one kind of printer (e.g., the Bell and Howell) to be printed upon another kind of printer (e.g., DeBrie). In some cases it may even be impossible to print a notched film at all on certain printers because of some construction difference in the arrangements for guiding the film with respect to the aperture. Once a film is notched for printing, it is often no longer practicable for another laboratory to print it. For this reason it is imperative that an original picture film shall not be notched for a timed print before the original has been completely edited and is completely ready for release printing. It is also a very good reason why the choice of a commercial laboratory is a weighty one for a film owner, and should be made only after the field has been carefully checked.
World War II saw a growth in electronics equipment from one-half billion dollars a year to about 40 billions per year, and it is only natural that electronic control should begin to be considered in preference to mechanical control for the various functions of printing, and, for that matter, other laboratory functions. Current design thought leans in the direction of such control for actuating light changes. One method is to use a small "bead type" lamp that produces a directed beam of light from its filament as a light source to actuate a photocell by light reflected from white high-reflectance pieces of adhesive tape (such as Scotch tape). This arrangement would substitute for the film notch and its associated delicate switch in causing the light change to function. The use of the reflected light method of actuating light changes would entirely avoid film mutilation that results from notching. Another arrangement uses magnetized filings attached by a cement.
Printing machines are of two general designs, the enclosed light-tight type that utilizes daylight-loading film magazines to avoid fogging of the raw stock and that has an enclosed light-tight film path, and the open type that is intended for use in a photographic darkroom. The advantages and disadvantages of the two types hardly need mention, since the considerations are quite like those related to daylight-loading versus dark