Laurence, Lionel · London, School of Optics · leaf 332
nastigmat, really combines all theadvantage of the others; it is one especially well corrected for astigmatism,and has a large flat field. Its working aperture is large, from F/4-5to F/6, and it is essential where rapid exposure is a necessity, and a largevariety of subjects has to be covered. Such…
Optics
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