Pentacon Orestor 2.8/135mm
Film d'essai (test film) of the Pentacon lens "electric" 2.8/135mm fitted to my Praktica VLC3.
For the test, I chose here a 36-exposure Rollei 400S Retro (i.e. Agfa Aviphot 400) that was exposed for 400 ISO following the readings of the Praktica camera or a Minolta Autometer III fitted with a 10° finder privileging the shadow zones. The Agfa Aviphot is a super-panchromatic film coated on a thin polyester base with a water-soluble black anti-halation coat on the back that should be removed by two or three presoaking bathes before developing. The film sensitivity is extended to the near infrared 780 nm. The film is known to gives excellent results to reduce the atmospheric blur and offer a spectacular resolution and contrasts that could help with a tele lens. The view were made the camera hand held with the eye-level pentaprism finder including the fFresnel micro prisms focusing screen,, at 1/500s at aperture ranging from f/11 to the full aperture at f/2.8.
Place Colbert, October 29, 2022
69001 Lyon
France
After exposure the film was developed for 10 min 30s using Adox Adonal (same as the Agfa Rodinal) developer at dilution 1+25 and 20°C. The film was then digitalized using a Sony A7 body and a Minolta Slide Duplicator with a Minolta Auto Bellows III with a lens Minolta Bellow Macro Rokkor 50mm f/3.5.
About the lens:
The Pentacon electric 1:2.8 f=135mm is the former German Meyer-Optik Görlitz Orestor 2.8/135mm lens, conceived in the sixties on the basis of a Sonnar optical formula. The company and the lenses incorporated the VEB Pentacon Dresden, Germany, in the seventies. This sample was also modified to include the electric transmission of the aperture coupling. The Orestor has also a less common 100mm companion. The 135 mm was massively produced and most of the Praktica enthusiasts had the 2.8/135mm in their kit as a compact telephoto lens not too heavy to be transported anywhere.
About the camera:
The Praktica VLC is of the 3rd generation (VLC3, 1978-1981) and was manufactured by "VEB Pentacon" (formally Zeiss-Ikon) in Dresden, Germany. It came with orignal Pentacon accessories including, a shade hood for its normal lens Pentacon "electric Multi-coated" 1:1,8 f=50mm, a waist finder, a straight magnification finder, and the regular pentaprism. There are also 6 different focusing screens, the Pentacon hot shoe for a flash, lens and body caps, and a Praktica ever-ready case.
The camera has a CdS photometric circuitry powered by an unusual 4.5V battery that I replaced by a set of 3 LR44 alkaline batteries in series. As the ASAHI PENTAX Spomatic SP, the bridge circuit is insensitive to the voltage difference. To be independent of the finders, the cell is functioning behind the mirror as in the Topcon Super D or the Miranda Auto Sensorex EE.
This Praktica operates at full aperture using an electrical transmission of the aperture using 3 contacts on the M42 lens mount. It could however operates any non electric M42 lenses at real aperture too by acting on the rotary switch at the top left. As for the other Praktica of the L series the shutter is made of vertical steel curtains making the X-flash synchro at about 1/125 s.
Overall Pentacon produced 85 000 Praktica VLC between 1974 and 1981 among about 3 millions of Praktica "L" (LLC MTL TL L etc).
Pentacon Orestor 2.8/135mm
Film d'essai (test film) of the Pentacon lens "electric" 2.8/135mm fitted to my Praktica VLC3.
For the test, I chose here a 36-exposure Rollei 400S Retro (i.e. Agfa Aviphot 400) that was exposed for 400 ISO following the readings of the Praktica camera or a Minolta Autometer III fitted with a 10° finder privileging the shadow zones. The Agfa Aviphot is a super-panchromatic film coated on a thin polyester base with a water-soluble black anti-halation coat on the back that should be removed by two or three presoaking bathes before developing. The film sensitivity is extended to the near infrared 780 nm. The film is known to gives excellent results to reduce the atmospheric blur and offer a spectacular resolution and contrasts that could help with a tele lens. The view were made the camera hand held with the eye-level pentaprism finder including the fFresnel micro prisms focusing screen,, at 1/500s at aperture ranging from f/11 to the full aperture at f/2.8.
Place Colbert, October 29, 2022
69001 Lyon
France
After exposure the film was developed for 10 min 30s using Adox Adonal (same as the Agfa Rodinal) developer at dilution 1+25 and 20°C. The film was then digitalized using a Sony A7 body and a Minolta Slide Duplicator with a Minolta Auto Bellows III with a lens Minolta Bellow Macro Rokkor 50mm f/3.5.
About the lens:
The Pentacon electric 1:2.8 f=135mm is the former German Meyer-Optik Görlitz Orestor 2.8/135mm lens, conceived in the sixties on the basis of a Sonnar optical formula. The company and the lenses incorporated the VEB Pentacon Dresden, Germany, in the seventies. This sample was also modified to include the electric transmission of the aperture coupling. The Orestor has also a less common 100mm companion. The 135 mm was massively produced and most of the Praktica enthusiasts had the 2.8/135mm in their kit as a compact telephoto lens not too heavy to be transported anywhere.
About the camera:
The Praktica VLC is of the 3rd generation (VLC3, 1978-1981) and was manufactured by "VEB Pentacon" (formally Zeiss-Ikon) in Dresden, Germany. It came with orignal Pentacon accessories including, a shade hood for its normal lens Pentacon "electric Multi-coated" 1:1,8 f=50mm, a waist finder, a straight magnification finder, and the regular pentaprism. There are also 6 different focusing screens, the Pentacon hot shoe for a flash, lens and body caps, and a Praktica ever-ready case.
The camera has a CdS photometric circuitry powered by an unusual 4.5V battery that I replaced by a set of 3 LR44 alkaline batteries in series. As the ASAHI PENTAX Spomatic SP, the bridge circuit is insensitive to the voltage difference. To be independent of the finders, the cell is functioning behind the mirror as in the Topcon Super D or the Miranda Auto Sensorex EE.
This Praktica operates at full aperture using an electrical transmission of the aperture using 3 contacts on the M42 lens mount. It could however operates any non electric M42 lenses at real aperture too by acting on the rotary switch at the top left. As for the other Praktica of the L series the shutter is made of vertical steel curtains making the X-flash synchro at about 1/125 s.
Overall Pentacon produced 85 000 Praktica VLC between 1974 and 1981 among about 3 millions of Praktica "L" (LLC MTL TL L etc).