The sciopticon manual, explaining lantern projection in general, and the sciopticon apparatus in paricular (1877)

Page scan 00032 from The sciopticon manual, explaining lantern projection in general, and the sciopticon apparatus in paricular

Record Details:

Title:
The sciopticon manual, explaining lantern projection in general, and the sciopticon apparatus in paricular
Date:
1877
Publisher:
Philadelphia, J. A. Moore
Volume:
The sciopticon manual, explaining lantern projection in general, and the sciopticon apparatus in paricular
Leaf #:
00032
Language:
English
Collection:
Books
Format:
Books
Contributor:
University of California Libraries
Sponsor:
MSN
Coordinator:
Media History Digital Library
Description:
Date Added:
July 19, 2022
Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




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.

SCIOPTICON MANUAL. 23 of an almost plano-concave flint, and a biconvex crown- glass lens, separated by a ring. It is seen that some marginal rays entering the lens A do not reach the lens J5, because of the length of the tube F F, which effects about the same result as the slight stop D D. The curvature of the field is somewhat exaggerated in the diagram, to remind us that an aplanatic lens cannot give a perfectly flat field without a stop. In this gene- ral form all portrait lenses mostly coincide, differing in regard to the focal length of the separate objectives A and B, the distance and size of the same, the position of the stops, &c. Considering Fig. 13 as representing a portrait ob- jective, the pencils JS SS proceed from an object com- paratively large and distant, forming a small image in the camera. Considering the diagram as representing a lantern objective, the order is reversed. A small transparency is in place of the curved line, which in its turn becomes the focus of incident rays, projecting upon a screen a comparatively large and distant image where the pencils S S S, if extended, meet in a focus of re- fraction. B is called the back lens in either case, as it is back next to the instrument to which the tube is attached.