Sometimes, you may want the light to fall on just a part of the scene, having the surrounds in shadows. The easiest way to confine the lighting is to place something dark, like a piece of black card, between the lamp and part of the subject. Experiment making a snoot with thick black paper and taping it to the flash.
When I first read this exercise I thought it would be a perfect exercise to try and create a film-noir effect which is very popular in the old movies.
I first tried this exercise using black foam rolled up into a snoot and attached to my speedlight with a rubber band (fig 01). I don’t think my background was right for this setup as I kept on getting rather hard shadows on most of my photos and I could not get the background to go completely black. I was shooting with a flash connector cord to my camera so I could utilize the TTL function on my flash, but the flash head kept on moving every time I changed position which changed the position of the light beam, which frustrated me no end.
I then tried it with my flash inside a collapsed umbrella and I quite liked the effect, but it it didn’t quite work out. Unfortunately I didn’t have a human volunteer for this exercise so the trusty rooster had to stand in again. I could not get the right light fall off that I was after.
I then noticed in Light, Science and Magic (p. 232) that a gridspot could be used to achieve the effect I was after. I wasn’t planning on spending more money on this section, so I googled how to make a gridspot. David Hobby’s Strobist site popped up with a snazzy DIY plan using black straws. Not finding any black straws in the local craft store, I decided to use black pipe cleaners and quickly twisted and wove a few pipe cleaners together to form my grid spot and wrapped it around my flash head and secured it with an elastic band (fig 03).
The result was much better and after experimenting on the placement and height of the light I persuaded my husband to sit for me (fig 04). Flash power was on full power, the light stand was positioned in front and about 1 metre from my husband and about 30 inches above his head. I definitely prefer the grid spot image.
Hunter, Fil et al, (2012). Light—Science & Magic An Introduction to Photographic Lighting. 4th ed. Oxford: Focal Press
More Cheap and Easy Grid Spots. Strobist [online]. Available from: http://strobist.blogspot.ca/2007/06/more-cheap-and-easy-grid-spots.html. [Accessed 24 January, 2015]