Catalogue of apparatus and materials required in the practice of photography, including both plate and paper processes : manufactured and sold by George Knight and Sons, philosophical instruments makers, &c., Foster Lane, Cheapside, London : illustrated with woodcuts (1851)
George Knight & Sons, author · London : George Knight and Sons · leaf 19
FOCUSSING APPARATUS. 15 … £ s. d. FOCUSSING APPARATUS. It having been clearly ascertained that many very excellent Lenses differ as to their chemical and optical focus, a ready method of ascer- taining the exact difference is very useful to the practical photographer. Claudet’s apparatus made portable, so that when not in…
George Knight & Sons · Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
![An illustration from Albertvs Dvrervs Nvrembergensis pictor hvivs aetatis celeberrimus, versus è Germanica lingua in Latinam : pictoribus, fabris aerariis ac lignariis, lapicidis, statuariis, & vniuersis demum qui circino, gnomone, libella, aut alioqui certa mensura opera sua examinant, propè necessarius, adeò exactè : quatuor his suaru[m] Institutionum geometricarum libris, lineas, superficies & solida corpora tractauit, adhibitis designationibus ad eam rem accommodatissimis : denuo ad scripti exemplaris fidem omnia diligenter recognita, emendatius iam in lucem exeunt (1535)](https://img.insideoutlibrary.com/img/200/ia-albertvsdvrervsn00dure-177-0.webp)