78
The connections between naturalistic art and optical
devices such as the camera obscura has been widely
discussed in modern times, but in the nineteenth century
the pictorial relationships were not seen as determin-
istic. Optical instruments were not the dominant basis
for works of visual art; they were designed to replicate
established visual conventions, and were valued more
as teaching aids and auxiliary help for specifi c problems
of perspective. Their productions only latterly validated
artistic training; the lens’s fi eld of view coincided with
the established awareness of a delineated frame, and its
focal planes recreated, but did not inspire, the artist’s
emphasis or selection of certain planes of the picture.
Optical aids predated the photographic camera, though
not by much; problems with focus and lens aberra-
tions meant that they were actually practicable for less
than a century before photography’s invention. Still,
photographic cameras incorporated earlier designs and
corresponding representational systems, even as the lat-
ter shifted from a unifi ed, Cartesian space to one more
fragmentary, subjective, and modern.
Relationships between vision and art were of great
interest in the nineteenth century, and French ‘realist’
and British ‘naturalistic’ painters aimed to represent
direct visual sensation as a means of rethinking repre-
sentation beyond imposed ways of seeing and the picto-
rial devices of academic painting. One might imagine
that photography had no such conventions and that the
camera simply recorded material reality. But there was a
similar argument to be pursued; does a photograph con-
vincingly represent what we think we see in the natural
world? While it might be assumed that a transcription of
the visible world required the most precise resolution,
it was recognised that the human eye had a very partial
view of nature, circumscribed by distance, atmosphere,
luminance, and fi eld of view. If these limitations were
true to the essential nature of human vision, then perhaps
distinctness was not the most appropriate or truthful
optical mode. Indeed, critics such as Charles Baudelaire
(‘The Salon of 1859’) and Charles Blanc (The Grammar
of Painting and Engraving 1867) criticized photography
for its detailed and inexpressive literalness, refl ecting
concerns, in art, with the validity of verisimilitude and
its rejection by those interested in more subjective or
expressive schema.
An aesthetic justifi cation for indistinctness empha-
sized its role in subduing disparities in tonal relations,
equating this with the production of “breadth,” a term
in fi ne art generally taken to mean the suppression of
complex detail in favour of broad, harmonious tonali-
ties. In 1853, Sir William Newton argued that the effect
of breadth in photography was determined by tonal
rendition and image resolution or focus. He believed
these attributes to be best represented by the calotype
process, used by photographers such as Henri Le Secq
and Benjamin Brecknell Turner (see under landscape)
well into the 1850s. Glass plate negatives produced a
higher resolution and better tonal separation, but these
attributes undermined breadth. In 1860, Thomas Sut-
ton made the same association with the glossy fi nish
of albumen paper: “the real charm of a fi ne subject
consists in a sort of mysterious impression of depth
and space; and a varnished surface injures this effect by
rendering the subject represented more intelligible in its
details, fl at, little, and vulgar” (Sutton 1860, 13). Sutton
equated sharp detail with literalness and banality, and
these failings were often identifi ed as characteristic of
photographic images.
Diffusion might counter these faults. In 1864, John
Traill Taylor recalled that Talbot had recommended the
interposition of translucent paper between the negative
and positive to reduce sharpness, especially in portraits.
(Taylor 1864, 27). Vignetting was used to a similar end;
a graduated fading at the image periphery was originally
produced by curvature of fi eld and inadequate cover-
age in single lenses, but the effect had an antecedent
in painted portrait miniatures and from the 1850s was
purposely replicated in photographs, usually through
the interposition of a mask.
Soft focus could be introduced by opening up the lens
aperture, as recommended by Noël Marie Lerebours
(see under Lemercier, Lerebours and Bareswill), or by
moving the lens relative to the negative plane during
exposure, proposed by Antoine Claudet and Joseph
Bancroft Reade. The camera could be vibrated during
the exposure, while the “vibrotype” used a spirit lamp,
lit in front of the camera to create a current of denser
air that veiled the object. From the 1860s, diffusion was
produced through the reintroduction of lens aberrations
such as astigmatism and spherical aberration. A num-
ber of lenses were designed to that end, most notably
John Dallmeyer’s ‘Patent Portrait’ lens (1865) and the
Dallmeyer-Bergheim lens (1897).
Without a serious rationale, diffusion might simply
be the abuse of a good lens or technical incompetence.
But soft focus was believed to have a physiological
basis, in being more true to human sight. In 1889, Peter
Henry Emerson adopted theories on vision and repre-
sentation from Hermann von Helmholtz and British
“naturalistic” painters such as Francis Bate and Thomas
Goodall. Emerson argued that the optical characteristics
most in keeping with natural vision were represented
by a simplifi ed, centralized composition incorporating
selective focus (see naturalistic photography). In the
1850s, similar debates concerned ‘natural’ binocular
vision versus the unnaturally fl attened picture space
produced by the monocular eye of the lens. The is-
sue shadowed the evolution of lens technologies; the
original single, meniscus lenses had a relatively shallow
focal plane, but newer combination lenses gave a more