hyposulfite การใช้

It is also called sodium hyposulfite or hypo.
Morse did not know if the shoot had been successful until he treated the daguerreotype plate with mercury and hyposulfite of soda.
According to Austrian chemist Josef Maria Eder, Daguerre was not versed in chemistry and it was Dumas who suggested Daguerre use sodium hyposulfite, discovered by Herschel in 1819, as a fixer to dissolve the unexposed silver salts.
In early 1839, he acquired a key improvement, an effective fixer, from his friend John Herschel, a polymath scientist who had previously shown that hyposulfite of soda ( commonly called " hypo " and now known formally as sodium thiosulfate ) would dissolve silver salts.
Highly theatrical and dramatically lit, her pictures are frozen stage sets, still-life psychodramas in which she cast eminent friends like poet Alfred Tennyson; historian Thomas Carlyle; and scientist J . F . W . Herschel, the Dr . Who look-alike who boosted photography by discovering a powerful fixing agent, sodium hyposulfite.