What's the noun for daguerrotype? Here's the word you're looking for.
daguerreotype
An early type of photograph created by exposing a silver surface which has previously been exposed to either iodine vapor or iodine and bromine vapors.
“It tracks the brief evolution of daguerreotypy in France, where the medium lasted barely two decades.”
“Once again, daguerreotypy was reduced to a geometry of abstract markings.”
“For a while daguerreotypy was a better medium than paper photographs, but the latter product soon offered greater convenience, economy and reproducibility.”