SUMMARY
For decades after photography's invention, subjects rarely smiled in portraits, a convention inherited from centuries of painted portraiture where open smiles were associated with lower classes or lack of decorum. While early daguerreotypes required long exposure times, by the 1840s, faster plates and improved lenses reduced sitting times to seconds, making smiles technically feasible. Despite this, the solemn, closed-mouth expression persisted until the 20th century, driven by the perception of portraits as formal, permanent documents. The widespread adoption of smiling in photographs was largely a result of marketing efforts, particularly by companies like Kodak, which made photography more accessible and informal.
TAKEAWAYS
Early photography adopted unsmiling conventions from painted portraiture.
Exposure times shortened significantly by the 1840s, making smiles technically possible.
The perception of portraits as formal documents discouraged smiling for decades.
Marketing and increased accessibility of cameras led to the rise of smiling in photos.