135/2.8[T4.5] STF
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![135/2.8[T4.5] STF](duze/135__2_8STF.jpg)
![135/2.8[T4.5] STF cross-section - thanks to KS from kkm forum](duze/135__2_8STF_prz.gif)
![135/2.8[T4.5] STF (xitek)](xitek/135stfapp.jpg)
![Dynax9 and 135/2.8[T4.5] STF lens (xitek)](xitek/d9+135stf.jpg)
![]() Sniff our hero in conjunction with my 7 |
Attempted to describe the glass with a few reasons, firstly I am the holder, and secondly it is a phenomenon on a global scale, the design of unique, users of Nikon and Canon in vain may seek a similar structure in the optical range offered by these manufacturers, the a third lens to the AF system is the only one where the focus is set manually, fourthly, an objective finding that contradicts the popular light and lens aperture is the same. Naszym bohaterem (nie przypadkowo wyt_uszczonym drukiem) jest Minolta STF 135/2.8 [T-4.5] , ju_ sama nazwa wygl_da kosmicznie a gdy rozwiniemy w szyku skrót - Smooth Trans Focus, dopiero robi si_ cholernie powa_nie. Our hero (no chance in bold type) is the Minolta STF 135/2.8 [T-4.5], the very name seems cosmically and when to develop the formation abbreviation - Smooth Trans Focus, until it gets damn seriously.
We will begin deciphering the names, Smooth Trans Focus is a free translation of controlled blur blur in an era when all the focus here fighting for a man turns his head just nieostro_ciami! Komu to potrzebne? Who needs this? A tym którzy lubi_ cieszy_ oko wspania_ymi w_a_nie (sic!) nieostro_ciami tak potrzebnymi w fotografii portretowej cho_ nie tylko. And those who like to enjoy the eye is great (sic) nieostro_ciami as needed for portraits but not exclusively. |
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![]() Lens unit. |
Since we are dealing with a typical focal portretówk_ should not be surprised, to 2.8 aperture and a light 4.5, as some are surprised, as this light, other than aperture? No different, the light of this lens is smaller because a significant proportion of light entering the lens ? die? na pewnym elemencie optycznym, który spe_nia niebagateln_ funkcj_ w pracy obiektywu. at a certain optical element, which satisfies the not insignificant role in the work of the lens. To nic innego jak element apodyzyjny, zbudowany z dwu soczewek przy czym jedna z nich wykonana jest z szarego szk_a !! Is nothing but an element apodyzyjny, built of two lenses with one of them is made of gray glass! In the figure we see a cross section through such an element, the filter density increases non-linearly from the inside out, causing a clear effect of the measure and the darker edges. |
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![]() Eye to eye with a filter apodyzyjnym | Apply a filter on photographs apodyzyjnego reveals very pleasant to look at the blurry edges rozp_yni_ciem course, even such difficult parts as bright points in the blur does not represent a problem for this lens. |
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![]() In the photo on the left, it is clear rings on the edges |
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![]() Clearly see two apertures - both near-maximum |
Another distinctive feature of construction are two mechanisms STF's aperture, "normalny" sk_ada si_ z 9 listków daj_cy ko_owy otwór, sterowanie ta przys_ona odbywa si_ tradycyjnie poprzez korpus ale tylko wówczas gdy pier_cie_ nastawu drugiej przys_ony jest w pozycji A (automat?). "normal" consists of 9 leaflets giving circular aperture diaphragm control of this traditionally takes place through the body, but only when the second adjusting the aperture ring is in position A (automatic?). Drugi mechanizm znajduje si_ przed pierwszym [patrz rysunek przekrojowy], posiada 10 listków a sterowny jest r_cznie pier_cieniem na obudowie obiektywu. The second mechanism is the first [see the cross-sectional drawing], has 10 leaves and is controlled manually ring on the lens housing. P_ynne nastawienie tej przys_ony zawiera si_ w przedziale 4.5 do 6.7, to w_a_nie ta przys_ona odpowiada za kontrole ostro_ci w nieostrych partiach kadru. Liquid attitude of the aperture is between 4.5 to 6.7, it was this aperture is responsible for checking focus on vague parts of the frame. |
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That's an example of the aperture responsible for the sharpness of motion blur | ||
![]() Aperture fully open f/2.8 T4.5 | ||
![]() Fully closed aperture f/2.8 T6.7 | ||
s you can see the blur wyastrzania is quite wide, it deserves to underscore the fact that all the time we have the depth of field corresponds to 2.8 relative otworowi! Equally interesting though not so strikingly work looks at the lens aperture domykaniu normal. tbc |
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