In this article I discuss the role the imagination
plays in the production of what I call artistic astronomical photographs. I examine
the entire creative process, which has been defined as “that stretch of mental
and physical activity between the incept and the final touch.” I begin with an
examination of some of the ways in which the imagination is exercised in traditional
artistic photography and in observational painting, in order to tease out the
similarities and differences. Following a brief explanation of the way artistic
astronomical photographs are produced, I examine these similarities and
differences and, in doing so, show the unique ways in which the imagination is
exercised in this form of photography. I go on to explain that this is because
of the nature of its subject matter. I conclude by demonstrating that, although
the imagination plays this unique role in artistic astronomical photography,
this does not compromise its photographic integrity.
aesthetics; astronomical photography; imagination; observational
and scientific astronomical photographs
There has been some discussion of astronomical
photography in the literature of aesthetics but, for the most part, it has
concentrated on photographs taken by professional scientific observatories,
such as the Hubble Space Telescope (HST). The ultimate purpose of
these observatories is to capture data for scientific research, and the
spectacular photographs that have been released for public consumption, processed
by members of the Hubble Heritage Project, are really just a by-product of
this. A spokesperson for the
project said, “[By] emphasizing
compelling HST images distilled from scientific data, we hope to pique
curiosity about our astrophysical understanding of the universe we all inhabit.” They
might therefore be regarded as “public outreach photographs.” Elizabeth Kessler praises
them and points out that many “bear a striking resemblance to earthly
geological and meteorological formations, especially as depicted in Romantic
landscapes of the American West.”
However, it must be emphasized that, for aesthetic
effect, the colors in some of these photographs are represented arbitrarily
and, in many cases, data from wavelengths beyond the visible range are
assimilated. Consequently they are sometimes referred to as false color images. This fact has prompted commentators
to question whether they truly represent reality and, if they do not, whether
they should just be considered “pretty pictures.”, As Martin Kemp says,
“[T]he ‘eye’ of Hubble is very much not a human eye. And the translation of its
‘perceptions,' some 370 miles into space, into brilliant cosmic landscapes
which are accessible to our visual system requires a level of contrivance even
greater than that of a traditional landscape painter.” As they are a by-product
of scientific data, I call this category of astronomical photographs scientific
astronomical photographs. Figure 1 is an example of such a photograph taken by
What these discussions have overlooked, however, is
the fact that, over the last fifteen years, modern digital technology has
progressed to such an extent that astronomical photographs, with aesthetic
properties, can now be taken by non-scientists using consumer-grade cameras and
optics often similar to those used by mainstream photographers. Furthermore, these
photographs are not produced for scientific reasons at all but are “purposefully
made in order to capture, engage and sustain aesthetic experience” and it is for this reason that I call them artistic astronomical photographs. In this article, I restrict the discussion to these sorts of astronomical
photographs so that a fair comparison can be made with what I call traditional
artistic photographs, which are all non-astronomical photographs that are made for aesthetic, not scientific, reasons. Figure 2 is an example of an artistic astronomical photograph.
Figure 1. Orion
Nebula. (Photograph courtesy of NASA)
Figure 2. Orion
Nebula. (© Stephen Chadwick)
I do not, however, include nightscapes in this
discussion. Although these often contain an astronomical element, usually the
Milky Way, they are more akin to landscape photographs, as an essential contributor
to their aesthetic success is the terrestrial foreground. The subjects of the sorts
of astronomical photographs that I wish to discuss are purely astronomical and include
nebulae, star clusters, and galaxies. These are the most interesting from a
philosophical point of view because they are largely devoid of the subjects of
traditional artistic photography. I must add that this article concentrates
solely on digital photography, partly because digital has largely superseded
film in most realms of photography but, more importantly, it is only by virtue
of digital technology that artistic astronomical photographs can be taken.
Although the imagination is extensively discussed in
philosophical aesthetics and art criticism, it is usually through its role in
the aesthetic appreciation of works of art. This is not, however, the concern
of this article, for I am interested in the role of the imagination in the creation
of works of art. Defining the imagination is not easy, as it is used in many
different ways in common parlance and in the literature of aesthetics. However, Berys Gaut
offers a useful analysis that seems particularly applicable to the way it is
exercised in the creation of photographs. He says, “[I]magination is free from
commitments to what is the case and to particular actions….As such, imagination
is peculiarly suited…to be the vehicle for active creativity, since one can try
out different views and approaches by imagining them, without being committed
either to the truth of the claims or to acting on one’s imaginings.” This means that the “imagination
allows one to be playful, to play with different hypothesis, and to play with
different ways of making things.”
Gaut characterizes four types of imagination:
propositional, objectual, experiential, and dramatic. While propositional
imagination, that is, entertaining a
proposition without committing to its truth value, is obviously central to all
human pursuits, it is the phenomenologically rich experiential imagination that
is the main concern of this article. Experiential imagining is
“the kind of case where imagining has a distinctive experiential aspect,” and, in
relation to photography, this experiential aspect is particularly visual and
can be referred to as visual imagining. It also should be
acknowledged that imaginings can be both spontaneous and deliberate. Kendall Walton
says, “[We]e sometimes decide on what to imagine…we form intentions to imagine
this or that and carry them out. Imagining is sometimes deliberate. But not
always. Often we just find ourselves imagining certain things. Our fantasizing
minds stray, seemingly at random, without conscious direction. Thoughts pop
into our heads….Like breathing, imagining can be either deliberate or
In this article I compare the way the imagination is
exercised in the production of artistic astronomical photographs with the way
it is exercised in the production of other observational pictures. An observational picture
is one that is derived from the artist’s immediate observations of the world.
Paintings can be observational if they depict the scene that lay in front of
the artist during the painting process. Obviously not all
paintings are observational, as it is possible to paint completely imaginary
scenes or realistic scenes derived purely from memory. Furthermore, even when a
painting is observational, it is not
necessarily realistic, that is, it does not necessarily closely resemble the
scene as it would have appeared to an observer standing next to the artist. For
the artist is free to paint the scene in whatever way it appears to them, and
the imagination plays a crucial role in this. As Jonathan Friday says, sometimes,
“as in the case of impressionists and surrealists, this manifests itself in a
picture representing visual experience of the world rather different from
ordinary perceptual experience.”
For example, Van Gogh’s Wheat Field with a Lark (1887) is an observational painting, as the
artist was painting that which was before him in a field outside Asnières (Figure
3). But an observer standing next to him would not have perceived this scene as
it is depicted in the final painting, for we all perceive and imagine the world
in different ways. This explains, along with variations in talent, why different
observational paintings of the same scene are never identical.
Figure 3. Vincent Van Gogh, Wheat Field with a Lark (1887).
Traditional artistic photographs are, on the other
hand, always observational pictures, as they are formed from the light captured
from the intentionally framed portion of the real world that was in front of
the lens when the shutter was released. I will show, however, that as with an observational
painting this does not mean that the resultant photograph will closely resemble
the scene as it would have appeared to an observer who stood next to the
photographer. For, by using the imagination, the photographer can control how
the scene is represented in the resulting photograph.
Artistic astronomical photographs are also essentially
observational pictures as they are likewise formed from the light captured from
the intentionally framed portion of the real world that was in front of the
lens when the shutter was released. However, I will show that, because of the
nature of their subject matter, they differ substantially from the previously mentioned
types of observational pictures, and this has an important effect on the unique
way that the imagination is exercised in their production. To accomplish this
it is important to first examine the way the imagination is exercised in the
production of these other observational pictures.
Imagination in observational painting
So what role does the imagination play in the creation
of an observational painting, a painting that is of something that lies in front of the painter? While it must be
acknowledged that all painters work in different ways, there are at least some
common ways in which the imagination is exercised that are central to the
creative process. What we find is that spontaneous and deliberate imagining is
used in four important ways.
First, visual imagining is central to the choice of
subject or scene, and the perspective from which it is to be painted. As Walton
says, objects in the environment act as “prompters” and it is these that
“prompt our imagination.”
Second, imagination plays an important role in
deciding which fine details of the scene to depict in the final painting. So,
for example, the portrait painter can choose not to include the necklace that
hangs around the subject’s neck, or the landscape painter is free to ignore the
horse that is grazing in the field.
Third, the artist may imagine that the painting will
be enhanced if some elements are added
to the scene. For example, the painter may imagine that the portrait will be
preferable if a necklace is depicted, even though the subject is not wearing
one, or the country scene may be rendered more tranquil with the addition of an
The fourth important use of the imagination concerns
how the scene is to be depicted in order to portray the artist’s intention.
This will involve the choice of colors, shades, brushstrokes and so on, all of
which might be influenced by the conventions held by the school of art to which
the painter may belong.
This is by no means an exhaustive list, and is not necessarily
exercised sequentially, for there is constant interplay among all four ways
throughout the whole creative process.
Imagination in traditional artistic photography
There are many philosophers who have argued that, in
some sense, photography is mechanical and causal, and that, furthermore, it is
this that distinguishes it from other pictorial art forms, such as painting.
For example, Walton famously claims that “objects cause their photographs and
the visual experiences of viewers mechanically,” while Robert Hopkins says
“photography…involves a causal chain free from the influence of people’s
beliefs and experiences.”, For André Bazin, it
is this mechanical characteristic that accords photography a kind of realism
that distinguishes it from other kinds of pictures. Walton also says, “[P]hotographs
are counterfactually dependent on the scenes they portray: if the scene had
been different the photograph would have been different,” which leads to his transparency
thesis that states that “photographs are transparent. We
see the world through them.”,
mechanical view of photography is correct, it would surely follow that the
imagination plays a lesser role in the photographic process as compared to its
role in observational painting. However, as I will show, photography is, in
fact, far from mechanical, and thus the imagination plays an extremely
important role, as we see if we consider the four uses of the imagination
explored in the previous section.
1) The imagination is used by the photographer to
decide what will make a good subject and from what perspective it should be
presented. Experiential visual imagining is central at this point because the
photographer has to visualize how a particular part of the scene in front of him
or her will appear in a photograph and in what way this will engage the viewer.
Choosing the correct lens is especially important as it is focal length that
determines field of view. As Gordon Graham says, “[T]he more imaginative a
photographer is, the more he or she is likely to select a point of view which,
left to our own devices, we would not have chosen,” and so “the photographer
gets us to see what we would not otherwise have seen.”
2) As explained earlier, in the case of observational
painting once the scene has been chosen, the painter has complete control over
which parts to include. For example, if the portrait painter does not wish to
include the necklace that hangs around the subject’s neck, then he or she is at
liberty to preclude it from the painting. By altering camera settings, this
control is also afforded photographers. First, by varying the aperture they can
adjust the depth of field, which results in different parts of the scene
appearing in and out of focus in the resultant photograph. By using this method
it is sometimes possible to blur some objects in the scene to such an extent
that it is impossible for the observer of the resultant photograph to know what
they are. Second, by altering the exposure length it is possible to effectively
remove objects and features from the scene all together. Consider Bill Brandt’s
Nude (Figure 4). It is highly likely
that the woman represented in this photograph had some skin blemishes, and it surely
goes without saying that she had a neck. However, by the expert choice of
exposure these features have effectively been removed from the resulting photograph.
So, just as the painter can decide not to include the necklace around the neck
in the portrait, the photographer can do the same in the photographic portrait,
and in both cases visual imagining is central to the achievement. What this
shows is that the imagination plays an important role in what fine details are
depicted, and so the resulting photograph is very much dependent upon the
photographer’s intentions and imagination.
Figure 4. Bill Brandt, Nude, 1952.
(Courtesy of the Bill Brandt Archive and the V&A)
3) The observational painter is, of course, at liberty
to add elements to the painting that are not present in the scene in front of him
or her. For example, while painting a landscape the painter may include an
imaginary horse, and this is why, when we observe the finished painting, we
suspend our judgement as to whether or not there was an actual horse before the
painter. However, this does not seem to be true for traditional artistic
photography for, as Savedoff says, “If there is a horse in a photograph, we
assume that there must have been a horse in front of the camera, since the
horse cannot be a product of the photographer’s imagination.” A photographer may
imagine that the tranquility of the countryside would be enhanced by the
presence of a horse but, without actually getting a horse to enter the scene,
there will not be a horse in the resulting photograph. As a consequence of this, we can say that, for
something to be considered a genuine photograph, it is a necessary condition that
if objects are depicted in it, then that which caused their depiction must have
been in front of the camera when the shutter was released. It seems, therefore,
that in relation to traditional artistic photography, this third use of the
imagination plays no part. Later, I will discuss adding objects into photographs
during the processing.
4) What about the fourth way that the imagination is
exercised by the observational painter? I have explained that once the painter
has chosen the scene and the elements that are to be depicted, including ones
to be added, the painter exercises imagination in order to depict this in a way
that fulfills his or her aesthetic intention. In order to achieve this, they
have to choose colors, shades, brushstrokes, and so on. Is there an equivalent
use of the imagination in traditional artistic photography, or is the creative
process complete with the release of the shutter?
Releasing the shutter is, in fact, far from the end of
the photographic procedure, for this action does not actually produce a
photograph. Rather, during the period of time that the shutter is open, all
that occurs within the camera is that the sensor detects the photons that
arrive from the scene and converts them into an electrical charge. As I have
explained elsewhere, in order for a photograph to be produced, the raw data
that have been collected by the sensor have to be processed by software. There
are two ways in which this can be achieved. The most straightforward is
to use the camera’s own firmware, the software that is installed into the
camera itself. This firmware is written in such a way as to translate the
settings that have been chosen by the photographer and apply them to the raw
data that was captured by the sensor. If the photographer
wishes, however, this internal firmware can be bypassed and the raw data downloaded
onto an external computer and processed manually. Doing so affords the
photographer the capability to alter many aspects of the photograph, such as colors,
shades, contrast, and sharpness. This fourth use of the imagination is,
therefore, extremely important in both traditional artistic photography and observational
However, as Jiri Benovsky says, “[I]f the image has
been ‘tampered with,’ one could ask…does it still count as a photograph? Are digitally modified
photographic images still photographs, or are they some sort of ‘digital pictures
based on a photograph,’ or not even that?” As we have seen, all digital
photographs are digitally modified and manipulated, and this is “an essential
and necessary feature of the process of production of digital photographs.” But, intuitively, there
does seem to be a limit to how much tampering can be undertaken before they
lose genuine photographic status, although where this limit lies is hard to determine.
As Benovsky points out, the “problem here is a problem of vagueness: there is a limit to the type and amount of
retouches that a digital photograph can be altered with while still remaining a
photograph, but it is a vague, underdetermined, and indeterminate one.”
For example, our intuitions tell us that if a
photograph of the Taj Mahal is slightly brightened or the color of the grass in
the foreground is made a little more vibrant, then it remains a photograph of
the Taj Mahal. On the other hand, if it is lightened to such an extent that the
scene becomes completely white or the grass is presented as pink, then our
intuitions tell us that it ceases to be a genuine photograph of the Taj Mahal. However,
while this limit is indeterminate, there does seem to be a vague objective measure that guides our intuitions, for
we can at least compare the photograph with how we would expect the depicted scene
to appear to the naked eye. If the photographic representation diverges too
much from this natural look, then we feel photographic integrity is compromised
and it just becomes a digital observational picture based on a photograph.
However, although using software to manually alter color
balance, contrast, and so on might seem acceptable up to some vague and
indeterminate point, can the same be said when data are actually added to or
subtracted from the photograph? Using software to subtract data from a
photograph, for example, removing pimples from the face of a model, is common
practice and, again, up to some indeterminate point, we do feel that
photographic integrity is preserved. Things seem somewhat different, however, if
software is used to add data. For example, the landscape photographer could
copy a horse from another photograph and superimpose it onto a photograph, thus
adding the tranquility that he or she originally imagined prior to releasing
the shutter. Our intuitions here suggest that photographic integrity is
compromised if any data are added. The reason for this is because, as we have
seen, for something to be considered a genuine photograph, it is a necessary
condition that if objects are depicted in it, then that which caused their
depiction must have been in front of the camera when the shutter was released. It
follows from this that, if an object is added in the processing stage, then
photographic integrity is compromised and it just becomes a digital observational
picture based on a photograph.
We are now in a position to turn to the issue of how
the imagination is used in the production of artistic astronomical photographs.
What I will show is that the way the imagination is used here differs somewhat
from the way it is used in the production of both observational paintings and
traditional artistic photographs, and this arises from the unique nature of
astronomical subjects and the way that the photographs are created. However, I
will also show that this does not compromise their photographic status and, as
with traditional artistic photographs, they are likewise observational
The creation of artistic astronomical photographs
So what is so unique about the subjects of artistic
astronomical photographs? Crucially, most extended astronomical subjects, such
as nebulae and galaxies, are too faint to be visible to the naked human eye. Furthermore, this is not because
of their vast distances from us and thus their apparently small size in the
sky. For although they would appear larger the closer they were to us, their
brightness would extend over a larger area and so their average brightness
would actually remain constant. They are, therefore, intrinsically too faint to
be visible to the naked eye. The only reason that the colors, shapes, and forms
of extended astronomical subjects appear in photographs is because digital
cameras, in conjunction with long exposures, can detect so much more light than
can be detected by the naked eye. It is this characteristic of astronomical
subjects that impacts on the way the imagination is exercised in the creative process.
To understand this, it is important to have some understanding of the way the
light that is captured by the sensor is converted into a final photograph.
In the last section I explained that, in the case of
traditional artistic photography, this can be achieved automatically, via the
camera’s own firmware, or manually, on an external computer. However, the
astronomical photographer cannot rely on automatic software because it is
written with the aim of processing data gathered from the kinds of subjects
that we encounter in everyday life. Consequently the only way to produce
artistic astronomical photographs is to process the data manually on an
external computer. As astronomical subjects are very faint, most of the detail
is hidden in the shadows; Figure 5 shows an unprocessed astronomical photograph
of the Pleiades star cluster, and, at this point, the only parts that are
visible are the very brightest stars.
The first step that the astronomical photographer
needs to take is to brighten the photograph so that the brightest and the
darkest parts of the scene are visible concurrently. The whole photograph
cannot simply be brightened linearly because, if it is, the brightest parts
become too intense and all contrast is lost, as shown in Figure 6. Rather,
through numerous tiny increments, the photographer has to choose which parts of
the scene to brighten and which parts to keep dark, in order to produce a
photograph that satisfies his or her aesthetic aim. However, as most of the
scene is imperceptible to the naked eye, this cannot be used as an objective
guide to ensure that the relative brightness across the photograph is correct.
Rather, at each step of the brightening process, the photographer has to
visually imagine what relative brightness levels will satisfy his or her
overall aesthetic aim.
Figure 5. The Pleiades, unprocessed. (© Stephen
Figure 6. The Pleiades, brightened linearly. (©
Figure 7. The Pleaides, brightened non-linearly.
Once the relative brightness across the photograph has
been accomplished to the satisfaction of the photographer, the colors need to
be balanced. In terms of traditional artistic photography, color balance is
usually relatively acceptable straight from the camera. This is because the
hardware and software are designed in such a way as to produce photographs with
colors that closely resemble what we perceive with the naked eye. If the
resultant color balance does not fulfill the aesthetic wishes of the
photographer, it can be altered in processing software, which is fairly
straightforward, as the photographer can use the colors we perceive in the
world around us as an objective guide.
The situation is very different, however, for the astronomical photographer, for as the colors
of astronomical subjects are imperceptible to the naked eye, they cannot be
used as an objective guide to achieve a correct color balance. From the data
that have been collected by the camera, it is obvious which parts of the scene
contain the most red, green, and blue but there is no objective way of
determining which shades they should be. This greatly affects the resultant
secondary colors and hence the overall appearance of the final product. As was
the case with brightness, in order to balance the colors satisfactorily, it is
necessary for the photographer to make subjective decisions prompted by the
imagination. Thus, as with observational paintings, no two astronomical
photographs of the same subject will ever be the same, even if the same person
repeatedly processes the same data. One such end result derived from the data
shown in Figure 5 is seen in Figure 7.
Imagination in artistic astronomical photography
Let us now consider the four uses of the imagination in
relation to astronomical photography.
1) The first use of the imagination concerns the
choice of subject. In the cases of observational painting and traditional
artistic photography, the “prompters,” that which prompts the imagination, are
objects and scenes perceived in the world around us. However, as the features
of astronomical subjects are imperceptible to the naked eye, they cannot directly
act as prompters. Rather, what directly prompts the imagination are photographs
of astronomical subjects, for it is only once such subjects have been
photographed that they can properly be examined. In order to accomplish this,
the astronomical photographer has to take short test exposures of possible
subjects. The results are extremely rough and grainy, as can be seen in Figure
8, which is a short exposure of a nebula with the catalogue name, Sharpless 308.
Using these test exposures as a guide, and by exercising visual imagination,
the photographer is able to visualize which subject will deliver the intended
aesthetic experience once the final photograph is produced. Figure 9 shows the
final result as inspired by the test photograph shown in Figure 8.
Of course, some of the most famous astronomical subjects
have already been photographed many times by different people, and so these can
also be used for inspiration. But, as we have seen, because of the subjective
decisions that have to be made during the processing stage, the appearance of such
photographs can differ significantly. So pre-existing photographs can only ever
be used as a rough guide to subject choice. Ultimately, visual imagining that
is prompted by photographs is crucial to subject choice, and this differs
substantially from the way it is exercised in subject choice in observational
painting and traditional artistic photography. This does not, however, alter
their status as observational pictures for, as is the case with all
photographs, the end result is derivative of the light that was observed by the
camera during the exposure.
Figure 8. Test exposure of Sharpless 308. (© Stephen
Figure 9. Final processed version of Sharpless 308.
2) In terms of using the imagination to effectively
remove objects from the scene, I explained that the observational painter has
total freedom. Similarly, prior to the release of the shutter, the traditional
artistic photographer has substantial control over this by altering the lighting
conditions and exposure length and by exploiting depth of field by adjusting
the aperture. The artistic astronomical photographer, on the other hand, does
not have this freedom for two reasons. First, because of the large distances to
astronomical subjects, they are all at infinity in relation to the photographer
,and so depth of field cannot be exploited. Second, as astronomical subjects
are relatively faint, long exposures are essential in order to maximize the
amount of light hitting the sensor in the camera. Thus the astronomical photographer
cannot and, furthermore, would not wish to effectively remove elements from the
resultant photograph in this way.
3) In the third use of the imagination, I showed that observational
painters are at liberty to add elements to the scene that is in front of them.
However, I went on to argue that it is a necessary condition for something to
be considered a photograph that, if an object appears in the photograph, that
which caused its depiction must have been in front of the camera when the
shutter was released. As a consequence of this, photographic integrity is not
maintained if data are added during the processing stage. This very point is
what lies behind the charge that scientific astronomical photographs are really
just pretty pictures. For the public outreach photographs that are created as a
by-product of data acquired from scientific observatories often do have data
added to them in the processing stage, specifically to enhance their aesthetic appeal.
This third use of the imagination is, therefore, very much at work in the
production of scientific astronomical photographs, and it is this that changes
their status from genuine photographs to observational digital pictures based
on photographs. This is not, however, the case with artistic astronomical
photographs, because these can be created without adding data. Thus, because
the imagination is not exercised in this third way, photographic integrity is, at
least prima facie, maintained.
So far I have argued that, in relation to artistic
astronomical photography, the imagination is uniquely exercised in terms of the
choice of subject, it cannot be used at all for removing fine detail from the
scene, and it should not be used for adding data if photographic integrity is to
be preserved. Does this mean that the imagination only plays a minor role in
the creation of astronomical photographs? This is, in fact, far from the case because
of the fourth way that the imagination is exercised.
4) While discussing traditional artistic photography I
explained that, in relation to color balance, brightness, sharpness, and so on,
there is a vague, indeterminate limit to how far they can be altered before
photographic integrity is compromised. I argued that while this limit is
indeterminate, there is a vague objective measure that guides our intuitions, for
we can compare the photograph with how we would expect the depicted scene to
appear to the naked eye. If a photograph diverges too much from this natural
look, then we feel photographic integrity is compromised and it becomes just a
digital observational picture based on a photograph. However, in relation to
artistic astronomical photographs, this objective measure does not exist
because the scene is intrinsically imperceptible to the naked eye. There is,
therefore, no way of knowing whether such a photograph has diverged too much
from the natural look to ensure photographic integrity is maintained. This is
obvious if we compare the photographs in Figures 8 and 9.
The absence of this objective criterion might suggest
that anything goes when processing artistic astronomical photographs, and so
the fourth way that the imagination is exercised is similar to the way it is exercised
by the observational painter. For, in the case of the painter, there is no objective
criterion that must be observed when choosing how to portray the scene, and so he
or she is able to use the imagination freely. If this is the case, then this
surely means that artistic astronomical photographs are not genuine photographs
at all but are just digital observational pictures based on photographs.
However, this is not the case for two reasons. First, in
contrast to the observational painter and in common with the traditional
artistic photographer, the artistic astronomical photographer can only work
within the confines of the light that has been captured by the camera. Second,
there is a vague objective standard that guides the processing of the
photographs, albeit one that is different from that used in traditional artistic
photography, and this arises from a basic understanding of some of the scientific
mechanisms that underlie astronomical subjects. For such knowledge enables the astronomical
photographer to make some broad decisions as to which parts of the photograph to
depict the brightest, where it is suitable to use contrast and sharpening, which
general colors are appropriate, and so on. It is, therefore, an understanding
of scientific mechanisms that guides our intuitions when it comes to deciding
whether a particular astronomical photograph is genuine or should really just
be considered a digital observational picture based on a photograph.
In this article I have shown that the way in which imagination
is exercised in the production of artistic astronomical photographs diverges
significantly from the way it is used in other forms of observational picturing,
which arises from the fact that its subjects are largely imperceptible to the
naked eye. First, unlike in observational painting and traditional artistic
photography, subject choice is dependent upon other photographs rather than the
scene as directly perceived by the artist. Second, the imagination cannot be exercised
to effectively remove objects from the scene. Third, and in common with
traditional artistic photography but contrary to observational painting, the
imagination cannot be exercised in order to add things to the scene if
photographic integrity is to be maintained.
Lastly, although there is much subjectivity in the way
artistic astronomical photographs are processed, it is not the case that the
imagination can be unrestrained, as with observational painting. For, in
accordance with traditional artistic photography, there is a vague objective
criterion that must be adhered to if photographic integrity is to be maintained.
However, the criterion that guides our intuitions differs greatly in these two
forms of photography. Because of their imperceptibility, it is a scientific
understanding of astronomical subjects that guides our intuitions when it comes
to deciding whether a particular astronomical photograph is genuine or whether
it should really just be considered a digital observational picture based on a
photograph. Whereas, in the case of a particular traditional artistic
photograph, no scientific knowledge of its subject matter is required in order to
decide whether photographic integrity is maintained; all we need to know is how
far the scene that is depicted diverges from the way it would appear to the
naked eye. Finally, observational painters do not require any scientific knowledge
of that which lies before them and, furthermore, their imagination is not
restricted by the way the scene appears to the naked eye.
Stephen Chadwick lectures in philosophy and astronomy
at Massey University in New Zealand and is also a respected astronomical
photographer. His first book, Imaging the
Southern Sky, was the first of its kind, and his forthcoming book, Starlore and Astronomy of the South Pacific,
explores other aspects of the aesthetics of astronomical photography. Many of
his photographs are on his website: www.southernskyimaging.com.
Published on February 22, 2017
 Monroe C. Beardley,
“On the Creation of Art,” Journal of
Aesthetics and Art Criticism, 23, 3 (1965), 291-304; ref. on 291.
 The most comprehensive discussion is Elizabeth Kessler, Picturing the
Cosmos: Hubble Space Telescope Images and the Astronomical Sublime (Minnesota:
University of Minnesota Press, 2012).
 M. Lynch and S. Edgerton, “Abstract
Painting and Astronomical Image Processing,” in The Elusive Synthesis: Aesthetics and Science, ed. A. I. Tauber
(Netherlands: Kluwer Academic Publishers, 1996), pp. 120-123.
 Shana Cooperstein, “Imagery and Astronomy,”
Leonardo, 47, 2 (2014), 129-134; ref.
 Elizabeth Kessler,
Picturing the Cosmos: Hubble Space
Telescope Images and the Astronomical Sublime (Minnesota: University of
Minnesota Press, 2012), p. 5.
 Travis Rector, “Image-Processing Techniques
for the creation of Presentation-Quality Astronomical Images,” The Astronomical Journal 133 (2004) 1-104; Ref. on 39.
 Anya Ventura, “'Pretty Pictures:' The Use of False Color in
Images of Deep Space,” 19 (2013). See also M. Lynch and
S. Edgerton, “Aesthetics and Digital Image Processing,” in Picturing Power, eds. Gordon
Fyfe and John Law (London: Routledge, 1988), pp. 184-221.
 Evan Snider, ‘The Eye of Hubble:
Framing Astronomical Images,’ FRAME: a
Journal of Visual and Material Culture 1 (2011): 3-21. See also Elizabeth
Kessler, ‘Resolving the Nebulae: The Science and Art of Representing M51,’ Studies in History and Philosophy of Science
38 (2007), 477-491.
 Martin Kemp, Seen/Unseen (Oxford: Oxford University Press, 2006), p. 242.
 For a detailed discussion see Stephen Chadwick and Ian Cooper, Imaging the Southern Sky (New York: Springer, 2012).
 Jonathan Friday, Aesthetics and Photography (Aldershot:
Ashgate Publishing Limited, 2002), p. 33.
 Examples of this form of photography can be
found in Michael Shaw, The Complete Guide
to Landscape Astrophotography (England: Focal Press, 2017).
 While astronomical photographs taken with film were certainly
extremely important scientifically, it is unlikely that most people would claim
that they had much aesthetic value. For a collection of such photographs, see
David Malin & Paul Murdin, Colours of the Stars (Cambridge: Cambridge University Press, 1984).
 See Leslie Stevenson, “Twelve Conceptions of
Imagination,” British Journal of
Aesthetics 43 (2003), 238-259.
 Berys Gaut, “Creativity and Imagination,” in The Creation of Art, eds. Berys Gaut
& Paisley Livingston (Cambridge: Cambridge University Press, 2003),
pp.148-174; ref. on 160.
 Kendall L. Walton, Mimesis as Make-Believe (London: Harvard University Press, 1990),
 Drawings, sketches, etchings and so on can
also be observational pictures. For simplicity, I use paintings as the exemplar
of this genre.
 For an excellent discussion of painting from
observation, see John Danvers, Picturing
the Mind (New York: Rodopi, 2006).
 Kendall Walton, Mimesis as Make-Believe (London: Harvard University Press, 1990),
 Kendall Walton, “Transparent Pictures:
On the Nature of Photographic Realism,” Critical
Inquiry 11 (1984), 246-277; ref. on 251.
 Robert Hopkins, “Factive Pictorial
Experience: What’s Special about Photographs?” Nous 46 (2012) 709-731; ref. on 710.
 André Bazin, “The Ontology of the
Photographic Image,” Film Quarterly 13
 Kendall Walton, Marvelous Images: On Values and the Arts (Oxford: Oxford University Press, 2008), p.127.
 Kendall Walton,
“Transparent Pictures: On the Nature of Photographic Realism,” Critical Inquiry 11 (1984), 246-277;
ref. on 251.
 Gordon Graham, Philosophy of the Arts (New York: Routledge, 1997), p. 52.
 Barbara Savedoff, “Digital Imagery and the Resources of
Photography,” Journal of Aesthetics and Art Criticism 55 (1997), 201-214; ref.
 See also Jiri Benovsky “The Limits of Photography,” International Journal of Philosophical Studies 22 (2014), 716-733.
 If this method is chosen then the imaginative
decisions made by software engineers also become directly involved in the
production of the final photograph.
 For an in-depth outline of this process see
Jiri Benovsky “The Limits of Photography,” International Journal of Philosophical
Studies 22 (2014), 716-733.
 Extended astronomical subjects do not include
planets and stars that would appear brighter the closer they were to us. There
are some extended subjects that are visible to naked eye, such as the
Magellanic Clouds and the Andromeda Galaxy.
 Kendall Walton, Mimesis as Make-Believe (London: Harvard University Press, 1990),
 I would like to thank the anonymous reviewers
for their valuable comments and the editors for their support.