Brooks Short - Tampa, Florida 
, Mar 02, 2007; 01:56 p.m.
A couple of weeks ago there was a thread by Juha Kivekas on "Cross Lighting"
with a reference to Chiaroscuro.
Chiaroscuro refers to light areas adjacent to dark areas in an image,
specifically the lighting technique of having a dark area of the background
behind the brighter side of the subject with a light area of the background
behind the shadow side of the subject.
This is a very effective treatment of the light on the subject relative to the
light on the background and adds a good bit of drama to a portrait. Juha was
speaking of the difficulty in creating this effect when using just one light.
It's relatively easy to create this effect using a second light on the
background but it can be done with just one light.
The trick is to angle the background so that it is not parallel to the camera.
Here's a simple, one light shot with the background parallel to the camera.
The light on the background is very even from left to right. Of course the
background could be darker by positioning it farther behind the subject or
lighter by moving it closer.
Background flat to the camera
Brooks Short - Tampa, Florida , Mar 02, 2007; 02:00 p.m.
You could try to shade the background on the left with a flag and you might be able to get the left side a bit darker than it is before the card itself intrudes into the shot.
By simply angling the background so that the left side is farther behind the subject and the right side is closer, a dramatic change in tone across the background is possible.
This is the chiaroscuro effect that Juha was talking about in his previous post and only one light is being used.
Angled background
Brooks Short - Tampa, Florida , Mar 02, 2007; 02:02 p.m.
The addition of a flag on the left to block light from the left side results in a bit darker area and a slightly quicker transition on the bkgd. from light to dark.
Flag added on the left
Brooks Short - Tampa, Florida , Mar 02, 2007; 02:03 p.m.
Adding a white foamcore fill card on the right opens the shadows on the subject.
Fill card added
Brooks Short - Tampa, Florida , Mar 02, 2007; 02:06 p.m.
Try this single-light Chiaroscuro technique youself the next time you want a graded background and are using just one light.
Here's a drawing of the actual setup. One flash in a small 2'x3' Chimera softbox, one small 2'x3' Matthews flag (you could use black posterboard) and a white fill card.
Setup
Juha Kivekas , Mar 04, 2007; 04:20 a.m.
Stacy Newgent - Indpls, IN , Mar 04, 2007; 09:20 a.m.
Thanks for posting this Brooks! I'm going to try this today. My background will be a wall though so I hope I can get the angle right- I'll post my results tonight :)
Brooks Short - Tampa, Florida , Mar 04, 2007; 10:45 a.m.
Thanks Juho. Those are great references.
Stacy, can't wait to see your results.
Stacy Newgent - Indpls, IN , Mar 04, 2007; 06:38 p.m.
Well- I tried it today but I don't have a good example to show you. There was quite a bit of sun coming in from the windows so not much of a gradient to speak of- and my "model" was not very cooperative I'm afraid. Since I can't angle the wall (obviously) I tried to keep her at a 45 degree angle to the wall...then she gave up and leaned on it :) I will try it again...
one try
Stacy Newgent - Indpls, IN , Mar 04, 2007; 06:39 p.m.
