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nobody

27 Iun 2014 00:28



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Cam asa lucreaza zoom-ul la acest obiectiv:
The optical zooming action of the Series 1 was different from most earlier zooms such as the Zoomar. The Zoomar was an "optically compensated" zoom. Its zooming cell and focal plane compensating cell were fixed together and moved together with a stationary cell in between. The Series 1 was a "mechanically compensated" zoom. Its zooming cell was mechanically cammed with a focal plane compensating cell and moved at different rates. The tradeoff for greater optical design freedom was this increase in mechanically complexity.
http://en.wikipedia.org/wiki/History_of_photographic_lens_design

Focalizarea se poate face din celula 1 si/sau 4, cum spunea si Catalin. Cel putin calibrarea la infnit, la focala de 70 se face din grupul 4, iar la focala de 210 din grupul 1.

Mai are si un mod "macro" in care toate grupurile sunt mutate mai in fata, practic asigurand un backfocus mai mare.

Apropo, filetul de la celula 1 este lipit din fabrica dupa calibrare. In manualul de service spune sa pui acetona sau metyl-ethyl-ketone pe intreg filetul pentru a inmuia adezivul. In caz extrem, tot in manualul de service spune sa folosesti un ciocan de lipit ca sa incalzesti filetul pana se topeste adezivul.