Focus The Array: The data processor is able to do more than add up stored signals: it can be designed to modify the amplitudes and the phases of these signals in accordance with the instantaneous positions (along the synthetic array) of the points at which they were received. By modifying the amplitudes, we can shape the array effectively so as to reduce the size of its side lobes. By modifying the phases as a function of range, we can focus the array at all ranges, providing not only higher resolution but uniform resolution at all ranges.
One spectacular seismic field instrument that has recently been used in a test station in Montana is the large aperture seismic array (LASA). This array of instruments, consisting of more than 600 seismographs buried in shallow holes, is dispersed over an area half the size of the state of Massachusetts. A similar giant array of this nature is under construction in Norway. These arrays record vibrations that reach them from the earth's interior.
She blundered her way through technique, resorting to any means to get desired effects. The blurred, out-of-focus images that many critics deplored were deliberate. She wrote to her friend Sir John Herschel that she hoped to elevate her art beyond
mere conventional topographic Photography-map making & skeleton rendering of feature & form without that roundness & fulness of force & feature that modelling of flesh & limb which the focus I use only can give tho' called & condemned as "out of focus'' What is focus-& who has a right to say what focus is the legitimate focus-My aspirations are to ennoble Photography and to secure for it the character and uses of High Art by combining the real & ideal & sacrificing nothing of Truth by all possible devotion to Poetry & Beauty-,19.
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Photography
