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.
Vjli THREE-DIMENSIONAL MOTION PICTURES such a letter is about 30 millimeters high on the screen. At a distance of 40 feet from the screen, the average per son with good vision can read letters 20 millimeters high, but he does not try to exercise his vision to this extent and cannot distinguish the courser details of the letters until they are about 80 millimeters high, the distinguish able details then having dimensions of about 10 milli meters. Probably the average critical observer does not notice extreme haziness of letters that are 0.1 millimeter high on the film. Even their being illegible may not be noticed, so that what has here been called a 0.004-mm. diffusion circle would be just tolerated at the center of the picture. This size of diffusion circle would be quite satisfactory at the border^ and nearly twice that size would be tolerated provided projection did not make matters worse. The figure 0.055 millimeter given above for projection is perhaps not to be added in its entirety to the size of the diffusion circle at the margin of the negative image, but the combined effect must be just about what has been considered allowable. In order to visualize the meaning of these figures one might hold an inside page of the New York Times at arms length. The "want ads" will be just legible. The individual letters, even if jumbled, would also be legible if they were distinctly formed. Such letters correspond to the 20-mm. screen letters of the above example or to 0.07-mm. film letters. Even the very best lenses will not reproduce such characters sharply; and, indeed, the reader in looking over the newspaper at arms length does not attempt to notice print of that size. He is not even attentive to the ordinary newsprint, which is half again as large. On the other hand, letters 40 millimeters high on the screen — 0.14 millimeter on the film, for which our diffusion circle is 0.05 millimeter—correspond