Greg
16-Mar-2016, 17:36
Recently was able to try out a 115mm f/5.6 Ultragon Lens in a Compur shutter with option of purchasing it. Research on this optic led me to the following:
"The 115mm f/5.5 Ultragon wide angle was introduced in 1950. It has about 85-90° coverage (literature values vary between 80° and 100°; it officially covers 13x18cm/5x7) and came in a Compur 2 shutter. It is seen in both the dial-set (early) and the rim-set (later) version of the Compur 2. It was quite fast for a wide angle: the competing lenses in 1950 were the Schneider Angulon 120mm f/6.8 (an earlier design by Tronnier), the 4 3/8 f/8 Goerz W.A. Dagor, the Rodenstock Perigon 110mm f/12 (a Protar V-type design), or the 4/4 double Gauss lenses like the Meyer-Görlitz Aristostigmat or the Kodak Wide-Field Ektar (f/6.3). The design of the Ultragon was unusual in that it was completely asymmetric, the powers of the groups are + - I + -. It combines the strongly curved front cell of a double Gauss Topogon/WF- Ektar-type wide angle with an anastigmatic back cell of 3 lenses in 2 groups. The back cell geometry closely resembles a convertible Protar VII cell with the lowest index glass element replaced by air."
OK... Was hoping it would cover Whole Plate...Tried it on my 8x10 and it did cover a lot of film area and at f/22 the corners were terrible in covering the 4x5 format. Regretfully returned the lens. Now am wondering why the optic I tried was completely in-adequate at even covering the 4x5 format. Anyone have and use this lens? Have the suspicion that the lens may have been remounted into another shutter. Maybe the spacing of the front and rear cells not correct?
thanks...
"The 115mm f/5.5 Ultragon wide angle was introduced in 1950. It has about 85-90° coverage (literature values vary between 80° and 100°; it officially covers 13x18cm/5x7) and came in a Compur 2 shutter. It is seen in both the dial-set (early) and the rim-set (later) version of the Compur 2. It was quite fast for a wide angle: the competing lenses in 1950 were the Schneider Angulon 120mm f/6.8 (an earlier design by Tronnier), the 4 3/8 f/8 Goerz W.A. Dagor, the Rodenstock Perigon 110mm f/12 (a Protar V-type design), or the 4/4 double Gauss lenses like the Meyer-Görlitz Aristostigmat or the Kodak Wide-Field Ektar (f/6.3). The design of the Ultragon was unusual in that it was completely asymmetric, the powers of the groups are + - I + -. It combines the strongly curved front cell of a double Gauss Topogon/WF- Ektar-type wide angle with an anastigmatic back cell of 3 lenses in 2 groups. The back cell geometry closely resembles a convertible Protar VII cell with the lowest index glass element replaced by air."
OK... Was hoping it would cover Whole Plate...Tried it on my 8x10 and it did cover a lot of film area and at f/22 the corners were terrible in covering the 4x5 format. Regretfully returned the lens. Now am wondering why the optic I tried was completely in-adequate at even covering the 4x5 format. Anyone have and use this lens? Have the suspicion that the lens may have been remounted into another shutter. Maybe the spacing of the front and rear cells not correct?
thanks...