An introduction to the science & practice of photography (1891)
Jones, H. Chapman (Henry Chapman), 1854- · London : Iliffe & Son · leaf 133
" were the first lenses of this character introduced. It appears that both opticians worked simultaneously in the invention of this lens, and that Steinheil was the first to issue them to the public. Dallmeyer's lens was preceded a few months by his wide angle rectilinear doublet, working at t^ to… … Fig. 30. of the rapid lens is sufficiently indicated by figure 30. Steinheil also introduced large angle aplanats, in which
Photography
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