Clolor and Shadows

Susan said.......One thing I did not say about the colored shadows
that appear in my jewelry photography 

Shadows are usually coloured - but our brains choose to ignore that
fact. Also, interestingly, they be either of the object colour or of
its opposite (complementary) colour. They are almost never ‘grey’ as
we tend to think of them. If you want to think of the two
possibilities let us imagine a red bowl standing on a white surface.
Whilst some of the shadow will be due to light simply being obscured
by the bowl, there will also be light reflected from the white
surface up onto the underside of the bowl and re-reflected back down
from there to colour the shadow. If the surface were coloured, this
would also have a modifying effect. Probably the most graphic
example of this is seen when watching snooker on the TV - all the
balls will be seen to have green undersides reflected from the green
baize and, of course, part of this is re-reflected back down into the
shadow. In other circumstances, the shadow will be mainly the
complementary colour due to the main colour having been absorbed out
of the white light. You will normally see this mainly in portrait
paintings where the shadows of the face are normally portrayed in
purple or green (the complementary colours of yellow and red). If you
try to paint the shadows as grey, the face will just look dirty and
not ‘right’. Our eyes and brains delight in playing tricks on us
which we do not normally recognise but, in this case, by changing the
way in which we see the object from a ‘normal’ 3D image to a flat
photograph also changes the way we see and understand what is there.

Best wishes,
Ian W. Wright
Sheffield, UK

Ok, had to step in here. As a fine arts major, this is something
very rudimentary but critical to understand.

Shadows cast by an opaque object consist of the complementary color
(opposite on the color wheel) to the color of the light source.
Most light (think sunlight or incandescent) is yellow, which produces
bluish/purplish shadows. This is very clearly seen on a sunny day
with fresh snowfall. The shadows produced are a lovely near indigo
blue color.

Shadow color is also influenced by the color of the surface on which
the shadow falls (for example, if the yellow-light’s shadow falls on
a red surface, the resulting shadow will be more a magenta than an
indigo. In SOME cases (where the base surface is highly reflective,
for example), the color of the object may also influence the shadow
color through a 3-way bouncing of light (light reflects from the
surface onto the object and is bright enough to reflect back onto the
object), but this is more common with the use of multiple light

Now, shadows of a transparent object are a different issue. They
start out with the same theory but are then transformed by the
refraction of the light source within the transparent object. In the
simplest case, think of a yellow light source passing through a
cloudy red object. The cast shadow will be… deep purple shading to
brown – blue shadows combined with the red/orange filtered light
leaking through the transparency.

So when setting up or editing photography of jewelry objects that
contain both transparent and opaque objects, think about these rules
of optics.

Karen Goeller
Handcrafted and Unique Artisan Jewelry