Using ring flash for portrait photography

Ring flashes are particularly popular with fashion photographers as they create almost shadowless light (the flash unit wraps around the end of the lens - hence light is coming from all directions), reduce the visibility of skin imperfections, produce a very soft-edged shadow, and remove the need for any other lighting. They're very expensive and used primarily in a studio setting.

I've just purchased a much cheaper variant from Speed Graphic, a ring flash adaptor which attaches to my Canon 580 EXII Speedlite (as shown in the above picture). It uses a system of internal prisms and reflectors to distribute the light evenly around the lens.

I had my first go with the adaptor yesterday and quickly realised that it's going to take some getting used to. It's not practical to use in low light as the unit completely blocks the autofocus-assist beam on the 580EX II. It considerably diminishes the power output of the flash and also seems to seriously perturb the E-TTL (evaluative through-the-lens) flash metering system, with some shots badly underexposed and others overexposed. I need to learn how the camera behaves when this unit is attached. Having said that, I managed to get some great results in situations that have previously proved problematic, such as my daughter Emily enjoying her bathtime. Lighting most bathrooms is tricky due to all the reflective surfaces, such as tiles and mirror, creating far too many shadows.

In conclusion, not an essential item, but I am pleased to have it in my arsenal of portrait photography gear.