Word: lensed
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
A valuable new photographic instrument has lately been purchased by the Observatory. It is known as a Ross-Geiss lens and will be used for photographing and charting the sky. It was constructed especially for this purpose, and will cover a larger field than any other instrument at the Observatory...
The largest refracting lens in use is that of the great Yerkes telescope, with an aperture of forty inches. The Lick lens is thirty-six inches in aperture; the Royal Astrophysical Observatory at Potsdam has recently acquired a thirty- one inch photographic refractor; and the Pulkowa Observatory has a thirty...
All the telescopes used in carrying on this work are operated in small sheds placed in different parts of the grounds, but each is controlled by a central electrical station. By the use of a switch board one man can operate from this station as many of the instruments as...
From the standpoint of photographic research the collection is valuable as an evidence that difficulties resulting from exceptional brightness, cold, and altitude can be successfully overcome. This was done by the use of a specially constructed camera provided with a long focus lens and isochromatic plates. Perhaps the best example...
Experiments are being conducted at the Observatory with a view to using the light of the stars as a standard of light in photography. It is the practice among manufacturers of photographic supplies to sensitize plates with lamplight of different degrees of brilliancy, and so the numbers of different makes...