For this shoot I wanted to mix flash lighting with the ambient light of fairy lights.
I wanted the fairy lights to be thrown out of focus to create a bokeh effect white lighting Katie with the flash.
The problem I knew I would have is that the fairy lights are very low in power and as both model and I will be holding them, very prone to movement so slow shutter speeds would create motion blur.
To achieve a bokeh effect, I need as wide an aperture as possible, f/2.8 in this instance, and create distance from the subject to throw them out of focus as much as possible. I set a shutter speed of 1/100 which would let more ambient light in than my maximum sync speed but also reduce motion blur from the fairy lights. At f/2.8 and 1/100 shutter speed I needed an ISO of 500 to expose for the ambient light from the fairy lights.
I turned the room's lights off so only the fairy lights are creating ambient light and closed the blinds so the room was in total darkness.
I metered my strobe setting the light meter to ISO 500 and adjusted until the light exposed Katie at f/2.8. Here is the resulting image.
The like of bokeh balls look interesting however cross Katie's face.
You can also see how the flash, hitting the light in Katie's hand is overpowering them making it hard to tell they're lit up at all.
A few shots in I noticed the side Katie's hair is laying is blocking the light, in some instances it created interesting shadows, but others it cast her full face into shadow.
Interesting shadows
Full face in shadow
I tried changing the angle I was shooting from to see how an image can change without moving the light or subject.
I really like these images. The unused barn doors you can see in the background helps to give a sort of behind-the-scenes feel and the shadows cast on Katie's face don't seem to be ass problematic compared to shooting head on.
Wanting to try and eliminate big shadows from Katie's face, I moved the light to the other side of Katie to avoid hitting her hair. I also switched lens to a 105mm macro lens knowing longer focal lengths produce a shallower depth of field.
However I noticed a problem when shooting with a macro lens, particularly in the studio.
I remetered the lights to achieve a f/2.8 aperture. However, at close focusing distances, the circle of light that hits the cameras centers grows, meaning not 100% of the light going through the lens is exposing the sensor. Nikon cameras fortunately report the change in what is known at effective aperture. However, I didn't pick up on this change in effective aperture until I saw the metadata. This resulted in ever so slightly underexposed images. Not so much the images are unusable but enough for me to realise it's important to be careful in noting the aperture the camera is reporting.
Metadata reading f/3
Edited to increase exposure 1/3 stop.
The term bokeh refers to the way a lens renders light when thrown out of focus. It is typically seen are round globules in shallow depth of field images.