Heligonal
Rodenstock Heligonal 21cm f/5.7 image by Dirk HR Spennemann (Image rights) |
The Heligonal is an asymmetrical Double-Anastigmat variant with a Doublet front and Quadruplet rear group,[1] produced by G. Rodenstock in München (Germany). The lens can be used both as a Double-Anastigmat and, with the removal of the back lens group, as a simple Anastigmat; the lens barrel has aperture markings for both options. Unusually, the lens has a 13-leaved diaphragm.[2]
The Heligonal was introduced in 1905 and well received in the press of the day as lens that was sharp across the entire image[3], even though later scholars were much more critical of the asymmetrical design.[4] While still advertised in 1910 in Sweden[5] and in 1911 in Estonia,[6] the Heligonal is not listed in the Rodenstock 1912 export catalogue to the USA.[7] It would appear that in Rodenstock's line-up it was quickly replaced by the symmetrically arranged Eurynar (which also sold at a much cheaper price) and that the Heligonal was apparently was no longer made by 1926[8] (if not already terminated earlier). The Heligonal seems to have had a limited sales market,[9] even though it had been offered in a wide range of focal lengths (12cm to 48cm, see below). In consequence, today, the pre World War I versions are very uncommon units on the collector's market.
Doppel-Anastigmat-Heligonal
On record are these focal lengths:
Lens design and cross-section[5] image by Dirk HR Spennemann (Image rights) |
- 12cm f/5.4 barrel lens[10]
- 15cm f/5.5 in shutter
- 15cm f/5.5 in shutter[11]
- 21cm f/5.7 barrel lens[12]
- 24cm f/5.7 barrel lens[13]
- 30cm f/5.9 barrel lens [14]
- 48cm f/6.3 barrel lens[15]
Apochromat Heligonal
- 60cm barrel lens [16]
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Rodenstock Heligonal 21cm f/5.7 |
Links
Notes
- ↑ All lenses are kitted.
- ↑ Diaphragm shown in this image (Dirk HR Spennemann via Flickr).
- ↑ Johnson, George Lindsay (1909) Photographic Optics and Colour Photography: Including the Camera, Kinematograph, Optical Lantern, and the Theory and Practice of Image Formation. New York: D. Van Nostrand Company. P. 128
- ↑ "Occasionally, for some reason, a designer will try the effect of combining two dissimilar cemented components about a central stop. It is hard to see the virtue of such an arrangement, except perhaps as an economy measure." (Kingslake, Rudolf [1989] A history of the photographic lens. London: Academic Press, p. 102).
- ↑ 5.0 5.1 Forsner's Fotografiska Magasin. Priskurant I 1910-11. Stockholm Örebro. p. 107 page image reproduced in post in www.largeformatphotography.info.
- ↑ Parikas, Johannes Ja Peter (1911) Fotografia Õperaamat. Tallin online copy, pdf. Advert in catalogue on p ii and in text p. 19 Fig 17).
- ↑ G. Rodenstock Lenses of Quality Catalog 1912 via www.cameraeccentric.com.
- ↑ M. Wilkinson and C. Glanfield (A lens collector's vademecum, 2001) Entry on Rodenstock.
- ↑ Serial number range from s/n 6328 (a 48cm) to s/n 27648 (a 30cm).—s/n 51013 (a 30cm) is probably a typesetting error in the auction listing.—All Rodenstock serial numbers of the Heligonal are before 1910.
- ↑ in Lechner's Stereoskop-Reflexkamera (ca. 1905) via www.photohistory.at;
- ↑ Apparecchio fotografico per cinetismi, a soffietto, a lastre G. Rodenstock via www.lombardiabeniculturali.it
- ↑ s/n 9547 (Photographica Collection Dirk HR Spennemann).
- ↑ s/n 12614 in Ernemann Globus G (at the seventh Westlicht auction); s/n 13897 (Seen in a Russian on-line auction May 2013).
- ↑ f/stops at: 5.9, 7.7, 9, 11, 18, 22, 31, 44, 61.— s/n 27648 (see in Chinese on-line auction June 2006; s/n 51013 on Kood 390 Studio Camera (Swedish auction archived via archive-ee.com.)
- ↑ f6.3 to f88; s/n 6328 worthpoint.com.
- ↑ Simon Kidd via flickr; XXX.