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eBook details

• Title: Photographs of Nebulæ and Clusters
• Author : James Edward Keeler
• Release Date : January 31, 1899
• Genre: Photography,Books,Arts & Entertainment,
• Pages : * pages
• Size : 2507 KB

Description

The main purpose of this volume is to reproduce and make available for study, the larger and more interesting nebulæ and clusters on the programme, sixty-eight in number. The thirty-six subjects not reproduced are for the most part small or apparently not of special interest. The difficulties attending the reproduction of astronomical photographs by mechanical processes are well-known to all who have made the attempt. It seems necessary to recognize, at least at present, that delicate details of structure will be lost, and that contrasts between very bright and very faint regions will be changed, especially if a good sky background is preserved; in other words, that the best obtainable reproductions fall far short of doing justice to the original photographs. Technical studies should be based upon the original negatives or upon copies on glass.

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