Hind, H. Lloyd (Herbert Lloyd), Randles, W. Brough (William Brough) · London : G. Routledge & sons, ltd · leaf 117
73 EYEPIECES use with apochromatic and high-power achromatic or fluorite lenses, and are only made to give small magni- fications, 2 and 4 times for the 160 mm. tube, which become 3 and 6 times if used on the 250 mm. tube. The 4 is the more useful eyepiece of the two. When in use an image of the… … Fig. 23 I'llOJECTtON EYEPIECE record the position necessary to obtain accurate cor- rection for any camera extension. In practice it is somewhat difficult to get the best focus of the diaphragm, and Messrs. Zeiss supply a tape by which the extension of the camera can be measured, and which…
Color photography · Photomicrography
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