Mr. Eisenberg. May I have this admitted as 751?
Mr, McCloy. It may be admitted.
(Commission Exhibit No. 751 was marked and received in evidence.)
Mr. Eisenberg. What is the enlargement here, by the way?
Mr. Shaneyfelt. Approximately two and a half times.
Mr. Eisenberg. Now, having reference to the chart, Mr. Shaneyfelt, could you explain it in a little more detail, the basis of your examination?
Mr. Shaneyfelt. Yes; the basis of the examination was a close microscopic study of the negative made in the camera to study the shadowgraph that is made of the edge of the aperture.
As the film is placed across the aperture of the camera, and the shutter is opened, light comes through and exposes the film only in the opening within the edges. Where the film is out over the edges of the aperture it is not exposed, and your result is an exposed negative with a clear edge, and on the negative then, the edges of that exposure of the photograph, are actually shadowgraphs of the edges of the aperture.
Mr. Eisenberg. Could you circle or mark with arrows the edges you are referring to as "these edges" or "this edge," that is, the edges of the aperture opening at the plane of the film?
Mr. Shaneyfelt. Yes.