How do primary sources make a light look motivated, and how do they set exposure for the key?
John Alton's 1949 book (a cinematographer's first-person account) gives a concrete procedure: name the light source, use a small test light to find the position that both lights the scene and looks as if it comes from that source, make that the key, then add modelling light while keeping the feeling of a single source. Exposure is a separate step after lights are placed, using an incident meter (Movie Makers 1953; LibreTexts). The word 'motivated' does not occur in the Alton text (search over the whole OCR text, 0 hits), so the term itself was not sourced from a primary text.
John Alton's 1949 book (a cinematographer's first-person account) gives a concrete procedure: name the light source, use a small test light to find the position that both lights the scene and looks as if it comes from that source, make that the key, then add modelling light while keeping the feeling of a single source. Exposure is a separate step after lights are placed, using an incident meter (Movie Makers 1953; LibreTexts). The word 'motivated' does not occur in the Alton text (search over the whole OCR text, 0 hits), so the term itself was not sourced from a primary text.
Curator qualifications: Excerpted evidence located (one unexcerpted row); motivated light and key exposure (links T02.06).
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://archive.org/download/in.ernet.dli.2015.167927/2015.167927.Painting-With-Light_djvu.txt",
"note": "candidate evidence excerpts"
},
{
"url": "https://human.libretexts.org/Bookshelves/Theater_Film_and_Storytelling/Video_Production_Handbook/09%3A_Lighting/9.06%3A_Lighting_Design",
"note": "candidate evidence excerpts"
}
]
}Evidence claims
- [sourced_fact] John Alton's 1949 book (a cinematographer's first-person account) gives a concrete procedure: name the light source, use a small test light to find the position that both lights the scene and looks as if it comes from that source, make that the key, then add modelling light while keeping the feeling of a single source. Exposure is a separate step after lights are placed, using an incident meter (Movie Makers 1953; LibreTexts). The word 'motivated' does not occur in the Alton text (search over the whole OCR text, 0 hits), so the term itself was not sourced from a primary text. · locator: candidate evidence excerpts source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |