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The influence of colour on pattern
perception in Fair Isle knitted fabrics
Elizabeth
Gaston in Fair Isle knitted fabrics
The influence of colour on pattern
perception
University of Leeds, UK
Elizabeth Gaston
University of Leeds
ABSTRACT: This paper is part of wider research into
colour and pattern perception in knitted Fair Isle fabrics.
Through careful colour choices within Fair Isle fabrics it is
possible to change the visual emphasis of the pattern and
create perceptual ambiguities. Knitted fabrics demonstrate
a grid framework of stitches on to which pattern can be
applied allowing scope for a wide range of pattern and
colouration development. Colour is one area of influence
on pattern perception. This paper will review how the
perceptual spatial positioning of colour can be used to
enhance or reduce the perceptual effects of the
figure/ground relationship, grouping by similarity and
grouping by “good continuation”.
1. INTRODUCTION: This paper is part of wider research
into colour and pattern perception in knitted Fair Isle
fabrics. Through careful colour choices within Fair Isle
fabrics it is possible to change the visual emphasis of the
pattern and create perceptual ambiguities (figure 1). Three
main areas of influence have been identified in creating
perceptual changes in pattern; these are the influence of
colour on pattern perception, the influence of pattern on
colour perception and the influence of material choices.
Theories of colour and pattern perception have been
analysed to determine how differences in pattern
perception arise. This paper will report on the concerns
affecting one area of the project, the influence of colour in
pattern perception, and how this relates to knitted fabrics.
2. FAIR ISLE KNITTED FABRICS: The structure of a
knitted fabric can be described in terms of horizontal rows
of stitches (courses) and vertical rows of stitches (wales)
resulting in an overall grid of stitches onto which a pattern
can be applied. This allows straight lines, horizontal,
vertical or diagonal; to be produced easily however curved
lines are less successful [1].
Fig. 1 The same design knitted in the same colours but in a
different order creates two perceptually different patterns.
The patterns in knitted Fair Isle fabrics are created from
geometrical and symmetrical repeating units. Each knitted
stitch, which shows on the technical face of the fabric as a
v, appears as a discrete unit of colour.
Despite the overall size of pattern used, technical
considerations limits the size of individual pattern elements
so that although the overall pattern size may be altered the
size relationship between the individual blocks of colour
will not change and the relationship between colour fields
remains the same.
Although only two colours are used in each row of
knitting, complex coloration is achieved by changing colour
use in successive rows. Traditionally the pattern (figure) is
knitted in horizontal bands of analogous colour and the
background (ground) is knitted in horizontal bands of
different analogous colour (figure 2). Manipulating the
relationship between the two colour fields can cause
changes in the emphasis of the pattern and so create
perceptually different designs.
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Gestalt principles of pattern perception states that the
relative size, surround, orientation and symmetry of one
area will also affect the viewer‟s perception of the area as
either figure or ground [7].
Fig. 2 The figure is knitted in red (pink), violet, blue and desaturated blue, the ground is knitted in varying neutrals.
3. THE INFLUENCE OF COLOUR ON PATTERN
PERCEPTION: The colour organisation of a knitted Fair
Isle fabric results in one colour field of the pattern to be
perceived as a figure and one colour field of the pattern to
be perceived as the ground. Ambiguity between which
colour field is perceived as the figure and which colour
field is perceived as the ground can be enhanced through
spatial positioning of colour. Liebman identified value as
more important than hue in the discrimination of figure
and ground [2] and in a previous study of the figure/ground
relationship in Fair Isle patterns in most cases the
dominant colour was found to be the lightest [3]. In
chromatic pattern the field that is perceived as nearer will
be experienced as a figure and the field that is perceived as
further away will be experienced as a ground [4].
Saturated colours are perceived to dominate and advance
on tints, shades and tones of de-saturated colour which
are perceived as distant [5]. Warm colours generally
appear in front of cool colours of similar saturation and
value. In chromatic colour in the same illumination on the
same background the brightest colour will be more
insistent however hues of similar value lack contrast [6].
Fig. 3 The smaller are of the black cross is perceived as the figure,
this is emphasised when the figure is surrounded by the ground.
The dominant perception of the smaller area as a figure is
reduced when the vertical axis becomes a diagonal.
The smaller of two areas is perceived as a figure. In figure
3 the diagram is perceived as a black cross on a white disc
rather than four white areas on a black disc. The effect is
emphasised if the small area is surrounded by the larger
area.
The orientation of the figure can however affect the
perception of the pattern [8]. A horizontal or vertical
direction (+) emphasises the field as figure; however, a
diagonal orientation of a cross (X), which is common in
Fair Isle patterns, can reduce the figural effect and the
larger spaces between the cross which now have a vertical
and horizontal axis can now assume dominance causing
figure ground ambiguity as seen (figure 3) [9].
Symmetry in at least one plane of an area also has the
effect of emphasising the position of the figure in relation
to the ground [10]; however, the geometric nature of Fair
Isle patterns results in both the figure and the ground
having symmetry in at least two planes. This can cause
figure/ground reversal as in the case of Rubin‟s vase/face
experiment [11].
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Gestalt principle of similarity which states that contiguous
areas related in form, size or colour are perceived as
belonging together optically [13]. This can have the effect
of emphasising the perceptual form of the figure (figure 6).
Fig. 4 The teal cross is perceived as a figure individually but
assumes the role of ground when repeated.
Figure/ground reversal can occur in Fair Isle knitted fabrics
where two pattern elements that individually would be
perceived as figures combine to create an area of ground
that assumes the role of a figure. In figure 4 the figural
effect of the teal cross is weakened by a diagonal
orientation and a cool, less saturated colour of lower
value. The assumption of the ground as a figure between
the repeated cross is emphasised with a strong vertical and
horizontal axis and a spatially advancing warm, saturated
colour of higher value.
Fig. 6 The Gestalt principle of similarity can influence the
emphasis of the perceptual form of the figure.
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Fig. 7 When the figure and ground are different in hue and value a
strong cross is seen. When the-re is similarity between figure
and ground the form of the cross is reduced.
Fig. 5 Reversing the colour fields has the effect of altering which
pattern element is perceived as the figure and which pattern
element is perceived as the ground
Colours close in value cling together perceptually and this
can alter the perception of form [12]. This follows the
In the repeating all-over pattern of a Fair Isle design this
can influence the perception of which part of the figure is
dominant through the spatial effects of colour and
figure/ground separation (figure 7).
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The Gestalt principle of Good Continuation is also
important in the perception of Fair Isle patterns. This
states that a smooth line is preferable to one with abrupt
changes (figure 8). Two intersecting lines are perceived as
a cross rather than two v‟s. [14]. Again, the spatial effects
of colour can be used to emphasise of reduce this effect.
Fig. 8 Two intersecting lines will be perceived as a cross rather
than two v‟s.
discrete units of colour can be segregated by the eye
colour contrast occurs [17]; however, in patterns with
high spatial frequency the opposite effect is noted and
assimilation of colour occurs [18]. However, White‟s
effect [19] and the inverted White‟s effect [20]
demonstrate that contrast and assimilation can occur at
the same spatial frequency and relationships between value
are important in determining which effect will take place.
Perceptual ambiguity can create illusory form. A contour
is usually described as the luminance boundary between
two areas.
Illusory contours can be created by a
configuration of line ends (figure 10) [21] which often
occurs in Fair Isle Pattern.
Good Continuation is particularly noticeable in Fair Isle
fabrics when it occurs to create amodal completion of a
figure (figure 9) [15].
Fig.10 Illusory contour formed from a configuration of line ends.
Fig. 9 Amodal completion produces the perception of overlapping
regular shapes rather than two separate irregular shapes.
Another effect created by form worth mentioning briefly is
the effect of brightness induction (figure 11) [22] in which
illusory form creates a perceptual difference in brightness
between two areas of identical colour.
4. FURTHER CONCERNS: The influence of colour on
pattern perception is only one area of influence in the
overall perception of pattern. It is worth noting briefly the
nature of other fields of influence.
Closely associated to the influence of colour on pattern
perception is the influence of pattern on colour
perception. The spatial frequency of a pattern has been
shown to influence colour perception [16]. Where
Fig. 11 The perceptual white rectangle appears brighter
then the background
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Material choices in the production of knitted fabrics will
also have an effect on pattern perception. There are nine
conditions of colour opaque, filmy, transparent, luminous,
dull, lustrous, metallic and iridescent. If one colour was
produced in all of these textures when measured it would
produce the same results however perceptually they
would be very different [23]. When used in a knitted
fabric, the increased reflectance of shiny or lustrous yarns
such as silk or viscose will change their perceptual value
and so change the relationship between the colour of
yarns with high reflectance and matt yarns of the same
colour.
Texture will also have an effect on the distinctiveness of
border between two colour fields. Conventionally yarns
used in knitted fabrics are spun from staple fibre which
produces an inherent hairiness on the yarn [24]. At the
border between two colour fields this produces a marginal
gradient and results in the colour of each field appearing to
be softer [25]. This is exacerbated by the v shape of the
knitted stitch.
Material use will also affect the scale of the pattern; a
course yarn will produce a larger stitch and therefore a
larger colour unit then a fine yarn. An identical pattern of
two different scales will achieve different hue modification
due to contrast or assimilation when viewed at the same
distance. When the distance from the viewer of the two
fabrics is such that the retinal image created for both
fabrics is the same size then the same hue modification
occurs [26]
5. CONCLUSION: The relationship between colour
perception and pattern perception in knitted Fair Isle
fabrics is complex and interdependent. Colour influences
pattern perception through modification in the relationship
between figure and ground and distortion of Gestalt
principles. Pattern influences colour perception through
contrast and assimilation and the creation of illusory form
and colour. Both of these influences can be modified
through material choices. Further work is being
undertaken to determine the relative importance of each
influence.
REFERENCES:
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Dover Publications Inc.
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Publishing Corp.
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Trench, Trubner and Co
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[19] White M. (1979) „A new effect of pattern on perceived
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