Ring flash is a flash unit that fits around the lens of the camera. I gives a very direct light and cool circular catchlights in the eyes. I have chosen to shoot this project with ring flash because it is punchy, directional and a little bit more unusual lighting. All the portraits of dogs I have found have been soft top lit images. and I want to jazz it up.
Here is a tutorial about using ring flash. http://www.thephoblographer.com/2013/08/20/the-phoblographers-introduction-to-ring-flash/#.VDRXYkusbwI .
I have found some examples on ring flash being used that best illustrate its look and what exactly it does. If just used on its own it can create a shadow all the way around the person as shown in shot 2. but I am planning on using it in a way that will be slightly softer more like shot 3 minimising that shadow and allowing the background to be neutral.