[M42] Pentacon electric 135mm f2.8

鏡頭資料》 http://www.praktica-collector.de/Pentacon_electric_2.8_135_MC.htm

Producer：Kombinat VEB Pentacon Dresden (Feinoptisches Werk Görlitz)
Kadlubek-Lens Number：KWD 1340
Production Period：1971 to 1990
Aperture range：2.8 - 22
Construction：4 elements
Aperture Angle：18°
Filter Size：screw in: 55mm
Focusing Range：1.7m to infinity
Coating：multi coating (blue reflection)
other：built-in retractable lens hood

我有兩支 M42 135mm f2.8 鏡頭，Pentacon 135 最近對焦距離較 Zenit 135 遠，為 1.7 公尺；一般鏡頭型號會寫在前鏡，而 Pentacon 卻是寫在內建的遮光罩上頭。單層鍍膜，抗耀光能力不佳。有 M/A 切換鈕，可支援全開光圈對焦，縮光圈拍照。

實拍照》
Pentax K10D + Pentacon electric 135mm f2.8

鏡身照》

鏡尾有幾個接點，Google 了一下，大致作用為機身快門擊發或半壓快門測光，以電流驅動鏡頭縮光圈。elecrtic 鏡頭只支援 Praktica 自己的機身，型號有 PLC、VLC、LLC 的機種開放光圈測光(可參考下表)，在這些機型上只要半按快門，不需要 (有些機身亦取消設計) 按下測光/景深預覽開關便可直接進行測光，這項功能如在其他的 M42 機身上，只能當成一般的 Auto 鏡頭使用，由於手上沒有 Praktica 支援此功能的機身，無法測試。
(From: http://www.wretch.cc/blog/jastatw/14379471)

 

L Type Cameras (From: http://home-1.tiscali.nl/~ferdix/history2.htm)

Model	Meter	Electric Lenses	Comments	Year
Praktica L	No	No	The basic model no meter	1970
Praktica LLC	TTL	Yes	TTL metering. Full aperture metering with electric lenses	1971
Praktica LTL	TTL	No	TTL metering. Step down metering	1972
Praktica LB	Non TTL	No	Uncoupled, non TTL meter	1972
Praktica VLC	TTL	Yes	LLC with removable viewfinder. Viewfinder compatible with Exakta RTL1000	1974
Praktica L2	No	No	Improved Praktica L. Multi Coated lenses	1975
Praktica LTL2	TTL	No	Improved Praktica LTL. Multi Coated lenses	1975
Praktica PLC2	TTL	Yes	Improved Praktica LLC. Multi Coated lenses	1975
Praktica VLC2	TTL	Yes	Improved Praktica VLC. Multi Coated lenses	1975
Praktica EE2	TTL	Yes	Aperture priority with electric lenses. Top of the line camera.	1977
Praktica MTL3	TTL	No	Third generation LTL	1978
Praktica PLC3	TTL	Yes	Third generation LLC	1978
Praktica VLC3	TTL	Yes	Third generation VLC	1978
Praktica EE3	TTL	Yes	Same as EE2.Aperture priority with electric lenses.	1978
Praktica MTL5	TTL	No	Fourth(?) generation LTL	1983
Praktica MTL5b	TTL	No	Fifth(?) generation LTL	1985
Praktica MTL50	TTL	No	Led information in the viewfinder. Otherwise the same as the MTL5b. The last of the screw mount Prakticas	1985