Sunday, 23 June 2013

Exercise: The lighting angle

The position of the light source in relation to the subject will create different effects, some of which will show the form, some the shape and some will enable the subject to be separated from the background.  The purpose of this exercise is to demonstrate this modelling effect by moving the light around the subject and also varying by varying the vertical angle between the light and the subject.  There are 3 sets:

  1. the light is horizontal in relation to the subject;
  2. the light is elevated and pointing down at 45 deg; and
  3. the light is directly above the subject.
This is best illustrated in the lighting diagram below which shows the basic positions.

My very patient model for the this was a mannequin head, which I felt was ideal for looking at the way light is shaped around a persons face.

Light horizontal

With the exception of the light being directly behind the subject, I kept all settings the same, as I felt this would best illustrate the effect, including the amount of light falling off the face of the subject.  The Speedlite was at 1/2 power and the camera settings were ISO 100, f/11, 1/125 sec.  Where the light was directly behind the subject, because I was shooting not only through the softbox, but also through the white backdrop, I increased the power setting on the Speedlite to full power.  The camera setting stayed the same.  Focusing was set to manual and lens stabiliser was off as I was using a tripod.
Front                                                       Right 45 deg,                                           Right 90 deg
In the set above, the first image is with the softbox as close to the camera as possible in the same plane.  It still was slightly to the right of centre, as evident by the shadows visible on the left.  The ideal would be for there to be no shadows at all.  As the light moves to the right, the amount of shadow increases on the face.  At 45 degrees, this provides a good modelling light revealing the form.
Right 135 deg,                                          Back                                                    Left 225 deg
As the light source moves towards the back there is more of a rim lighting effect, separating the subject from the background.  As there is somewhat less light falling on the background, it gets darker, showing how the action of the light can usefully alter the tone of the background.  With the light at the back, a silhouette is formed showing the shape of the subject.  I did have some light spill, as I did not use black 'stoppers' either side of the subject to kill such spill.  Moving the light to the left of the camera, in the last image of the trio above, this provides an interesting lighting effect, as the face is turned to that side.  The left of the face is lit with this side light giving a good sculptural effect and some drama.
Left 270 deg,                                                Left 315 deg,                                                              Front     
The first of the images above is displaying, what is referred to as "Rembrandt" with the light on the right in the shadow.  This is not true Rembrandt light, as it should be more pronounced and the light elevated.  Again, the form of the face is well shown.  The centre image now has more light on the face, and elevated, would be a good portraiture one-light setup, if elevated.  Finally, I managed to squeeze the softbox more effectively against the camera and the flatness of the lighting can be seen.

Light elevated and pointing down at 45 degrees

For this sequence, I changed the camera settings to ISO 100, f/8, 1/125 sec., adding an extra stop exposure due to the increased distance of the light from the subject.
Front,                                                      Right 45 deg,                                              Right 90 deg
Due to the angle of the head, when the light was above the camera, in front, there are shadows developed on one side of the face, so the lighting is not as flat as it otherwise would be.  At 45 degrees to the subject, there is considerable shadow to one side of the face, but the features are well modelled.  Withe the light side on, most of the features are hidden by shadow, so this would not be a particularly useful lighting setup.

Right 135 deg,                                              Back, above                                             Left 225 deg
The first of this sequence is not really helpful at all.  from the back, there is too much light for a silhouette, but there is good separation.  Throwing some light back using a reflector would make this useful.  There is already some light being thrown up from the white background paper on which the head is standing, as can be seen from the light areas under the chin and nose in particular.  Moving to the left, this has the makings of a Rembrandt style lighting.

Left 270 deg,                                    Left 315 deg
The final two in the sequence, as I did not retake a shot from the front.  The first is very much a Rembrandt style light, with the triangular light area within the shadow on one side of the face.  The second of these, provides a good modelling light, with a butterfly shadow developing under the nose.

Light directly above the subject

The camera setting for these was ISO 100, f/11, 1/125 sec.

Above                                              Above and back                                          Above and front
Of the 3 in this sequence, the last, with the light above and slightly to the front is the most useful.. It provides good shaping and ' due to the shadows falling of the cheekbones, gives a more slender look.

In terms of choosing which lighting setup reveals the form of the subject best, then I would go for the light to the left at 315 degrees.  This is an extension of the Rembrandt light, but the face has been opened up due to less shadow, which now creates a more sculpting effect on the opposite side to the light.

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