Conversation so far:
Was Edward Weston a writer or were things written about him?
Edward Weston was a prolific writer.
What did Edward Weston write about?
Edward Weston wrote dozens of articles and commentaries, and he hand-wrote or typed at least 5,000 letters to colleagues, friends, lovers, his wives and his children.
Was Edward Weston a published writer?
Edward Weston's Daybooks were published in two volumes totaling more than 500 pages in the first edition.
Did Edward Weston ever write any books?
Edward Weston's Daybooks were published in two volumes totaling more than 500 pages in the first edition.
Were Edward Weston's Daybooks successful?
When combined with his photographs, Edward Weston's writings provide an extraordinarily vivid series of insights into his development as an artist and his impact of future generations of photographers.
Did Edward Weston write anything besides the daybooks and article and letters?
Among Edward Weston's most important early writings are those that provide insights into his development of the concept of previsualization.

Question: What were those writings?
Self-contained rewrite: What were those writings?