Monday, 8 October 2012

Exercise 36 Softening the light

Softening the light is the first of the Light exercises involving the use of artificial light sources and explores the importance of the angles of incidence and the intensity of the light.  There are two key texts that accompany this part and they are Hunter et al (2011) recommended in the course notes, and Arena (2011) which covers the use of Canon flash systems (see references in the sidebar).

My first shots were of a simple still life related to Chinese food and I shot this using both a constant light source and a flash.  The constant light was a 300 watt equivalent daylight balanced fluorescent with a ‘lampshade’ reflector and the flash shots were taken using a Canon 580 speedlite.  The diffuser I used was a sheet of corrugated translucent packaging stiffener as sent out in the post to protect prints and is far better than anything I have ever paid money for!  Both light sources were placed above the still life set up and slightly to the right of vertical.
The un-diffused constant light generated a well-defined shadow with moderately hard edges under the chopsticks, which I had rested on a rice bowl to ensure that there was enough space underneath to throw a shadow if there was to be one, although this would have had harder edges if the chopsticks had been closer to the menu.  The shadow was most pronounced on the pale paper of the menu and rather less so on the cloth.  When the diffuser was positioned immediately under the light the shadow became much more diffuse and fainter, almost disappearing where the shadow ran across the cloth, and the edges were far softer in comparison to the un-diffused version.  The naked light source brought out better definition in the small details of the cloth and gave some real identity to the highlights whilst also improving the contrast, whereas the diffused version made these rather dull in comparison; I would expect to be able to fix this in post-production, but that was not the point of the exercise!  Overall, I would say that the shadows were far more acceptable in the diffused version but that it would be necessary to boost the highlight detail in the cloth to roughly match that in the image taken with the naked light source if an optimised image was to be obtained.

Constant light - no diffuser
Constant light - plus diffuser

Although it was not a requirement of the exercise, I repeated it using flash to see whether there really were any differences – I have always preferred constant lights to flash as it seems a faster way of obtaining the final photograph as it is possible to see what the outcome might look like from the outset, whereas flash has always been a journey of discovery for me thus far!
Flash - no diffuser
Flash - plus diffuser

The un-diffused flash gave the image some real punch and improved contrast over the constant light, but the main differences were the intensity and blackness of the shadows as well as the greater hardness of their edges, due to the flash being a smaller light source but also of far greater intensity.  This was especially prominent where the shadows fell across the cloth where they were black and sharp as opposed to the outcome with the constant light.  Positioning the diffuser in front of the flash head softened the shadows dramatically although they were still quite dark compared to the diffused constant light.  The diffused flash retained highlight detail and contrast better than was apparent from the constant light and overall I felt made a better image.  However, getting what I wanted with a flash set up would still have required much more experimentation compared to the constant lights where I could see what I was going to get before I took the shot.

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