1840, 22 January
[Daguerreotype exposure times, Belgium] The Star and Conception Bay Journal (Newfoundland)

Newspaper article
Internet - Original source ill-defined
1840-01-22 - The Star and Conception Bay Journal Vol V, No 289
 
"In Paris the Daguerreotype is being used for the purpose of obtaining likenesses. And in Belgium, at the opening of the Courtrai railroad, at which King Leopold, his court, and a numerous staff, with a vast concourse of people will attend, it is proposed that at a preconcerted signal by cannon, all persons present shall remain immoveable for seven minutes, while the Daguerreotype from an exalted station is taking a view of the vast assemblage, the railroad, the loaded locomotive, &c., which view will afterwards be inclosed in lead, and deposited under the first stone of the foundation of the station at Couatrai."
 
(Alan Griffiths, 13 July 2025) I'm indebted to Jeff Ward, The Early Light Project, for bringing this article to my attention.
 
LL/130847