Check Vade Mecum
1866 Rapid Rectilinear f8.0 4-48in (14foci.) Q5
Dallmeyer often illustrated the structure of the WAR but seldom the RR. The layout shown may be authentic (Da028) and seems to show a lens with rather thin glasses compared with the continental types, especially Steinheil's. The RR was a lens for normal general use, covering a good angle and being symmetrical or nearly so, with the result that it was free from distortion. Thus it displaced many of the early meniscus and triple lenses but the meniscus continued on sale at lower prices and to customers who valued the freedom from flare it gave. RR was not a cheap lens, at least until it was the low price version of later designs. It is said to have used new flint glass from Chance, and the date of issue may have partly depended on this. Later lenses were often of flint and crown. (eg Amateur Photo 03/04/1991, p243 which cites crown for the positive and flint for the negative.) It caused some tension with Grubb who had used the meniscus base of half a RR and patented it: and with Steinheil over priorities. The outcome was Steinheil was first by a short period but did not manage to get Patent cover for it in the UK. Dallmeyer's patent was No2502 of 27/09/1866. The use of the "Grubb" Patent meniscus layout went back to Ross in the Collen lens and in that sense the Aplanat and RR were of equal novelty. In experience, early Dallmeyer RR lenses are not too common, that seen being at No 39,78x (1886) in brass with Waterhouse stops. In use it was an excellent performer. The English tradition was to be to make the RR in f8 or f7.7, to cover a little more angle than the European Aplanat at f7.0 as there is a trade off of aperture against angle in these designs. A further compromise was the Portable RR: some makers offered this as a light version at about f11, with some increase in angle. A Dallmeyer lens may be of this type but it is not listed as a version in the adverts.
Note A large 60in f10 version is or was in the Science Museum, London.
The RR was still suggested as a valuable lens stopped down in 1920 when the price of new lenses had increased and workers were looking for cheaper alternatives. (B.J.P. 12/03/1920) But ominously the writer says only good ones will do- the RR was made by many others and often these were of very poor quality. Dallmeyer examples are not too easy to find but well worth looking for.
In 1872, Dallmeyer supplied the projection lenses for Mr E. Muybridge for the trotting horse study.
Fig 024 020 Dallmeyer RR about f8/11in No39,738; WAR about 4in No44,022.
Lake Price in 1868 had only just obtained an RR as it was 'recently constructed' so it seems to have gone on sale noticeably later: he had several WARs. He describes it as for 60-70° max, and having smaller glasses identical front and rear. It is aplanatic (ie can be used at full aperture) and at f8, is 4x the max speed of the WAR: and twice the speed of the Dallmeyer Triplet and the Orthoscopic. Price had only used his for copying but (due to its symmetry and design) was able there to speak most highly of its qualities, and say it was a very remarkable instrument.
An 1875 Summary. This list is based on an advert. and is almost a summary of J.H.D.'s career. C2 Extra Quick Acting Portrait for Children (EQAP) It was made as 4.5in, and later 6in.
In the 1890's this was f2.2, and as f1.0 to special order. Structure a version of the Petzval.
B1-4 Quick Acting Portrait 4.5, 4.75, 6.0in.
In the 1890's this was to become the B-series, at f3.16, f3.0 for 6-17in.
B Quick Acting Patent. 6.0, 8.0, 12in. This was the adjustable softness version.
A1-6 Ordinary Intensity (Patent) 6 sizes for 1/2plate to 20x16in In the 1890's this was f6.0, 10-30in.
D3-8 Rapid Portrait and Group in 6 sizes for 1/1plate to 25x20in. (Portrait RR?)
[Dallmeyer may just have been getting a special grade of glass for some lenses since Frydman and Wright, B.J.P. 29/10/1987 p1281 noted that there was a measurable radiocount rate suggesting the presence of Thorium in the glass, which may well have been a rather improved optical grade as a result. It just may have originated in mid- Europe since such properties will not be normal in such glasses.]
In the 1890's the D-series was f6.0, 9-37in.
Stereo Petzval and RR lens pairs. The 1889 list gives these as:
(a) Patent Stereographic, 3.75in plain or with rack&pinion. This was probably a Petzval type as it was more costly than the next item.
(b)Quick Acting Single Combination No1, 4.5in focus, No2 6in focus.
(c) Rectilinear Stereo Lenses in 2.0 and 2.5in.
NB This was an unusually varied list offered in 1889, as the restricted size of stereo cards meant that no great range of foci was needed. Stereo pairs are moderately regular at auction and must have been an important part of the sales. Two examples were at Nos 692x where one number seems to cover the pair, and a later pair at No25,15x and 25,15x- ie sequential numbers.
Optical Lantern Lenses These in 1889 were offered in No1 in 1.5 and 1.75in dia, No2 in 1.75 and 2in dia.
RR view lens (Patent) in 6, 8.25, 11, 13, 16, 17.5, 19.5, 24, 30, 33in.
Wide Angle Rectilinear (Patent) in 4, 5.25, 7, 8.5, 13, 15.5, to 19in.
This was listed as use 6.5in for 10x8in, for 100°, f16 to focus and then stop down.
Wide Angle (Patent) 5.25, 7, 8.5, 10, 12, 15, 18, 22, 25in.
This list changed only slowly over many years, eg. in 1889 it was much the same with the addition of the: (a)New Rapid Landscape, in 7 sizes 9-30in, and
(b) lantern lenses.
Some lenses had iris stops, apparently by 1875, at No24,06x.
1878 Rectilinear Portrait f3.0 in 6, 8in only, and probably a portrait RR.
1880 there may be a new Quick Acting Landscape here. Certainly a Landscape No32,123 for 10x8in was noted at auction from this period.
Wide Angle Landscape f15 made in 5.25, 7, 8.5, 9, 10, 12, 15, 18, 22, 25in.
The usual published layout was Da016, but two versions of the 18in at least existed and the difference is now obscure.
1884 Rapid Landscape f11 5-30in. in 9 foci. This is a 3-glass meniscus. There was a tendency to use rather long lenses for the plate here and with many menisci, so that only a limited angle was used. Coverage was 40°, or up to 60° if stopped down. They may be f8 to focus. By 1889 it was listed as:
No1, 9in for 1/2plate; No2, 12in for 1/1plate; No3,15in for 10x8in; No4, 18in for 12x10in; No5, 22in for 15x12in; No6, 25in for 18x16in and No7, 30in for 22x20in.
1887 Rectilinear Landscape f14 8.5-32in in 7 foci for 60°. This was not an RR but a 1+2 glass layout and rated by some users as the best of these lenses made with the old glasses only. It seems to be rather scarce as the new glass lenses were soon to come in. It is suggested to use 13.5in for 10x8in, Da008, (B.J.A.1889, p599). Traill Taylor descibes it as being like the old 3-glass meniscus Da 005 but with the rear crown glass mounted separately the other side of the doublet, and reversed. It was designed quite separately from the rather similar Goddard design, which had no public exposure.
It was seen in alloy mount with iris from 1890, with 1888 Patent claim, at No47,42x. The review says free from distortion, as one of the crown elements of the Dallmeyer triple has been reversed, and acts as the positive element, while the other two form a pair of little focusing power but act to correct the aberrations of the positive. The editor (Traill-Taylor) seems to have been well aware of this in advance and may in fact have helped the designer. A provisional patent was granted on 02/02/1888 for a 'new' Rectilinear Landscape lens, and the 1889 BJA advert. lists 7 sizes.
No1, 8.5in for 1/2plate; No2, 11.5in for 1/1plate;
No3, 13.5in for 10x8; No4, 16.5in for 12x10in;
No5, 20in for 15x12in; No6, 25in for 18x16in;
No7, 32in for 22x20in.
