Focus is what is in the cameras plane of focus (adjusted by the focus wheel on the lens). Focussing on near objects blurs the background and focussing on further away objects blurs the foreground. Although, if you use a narrow aperture (high number), (which is how much light the lens allows to reach the sensor), the whole frame is in focus, and if you use a wide aperture( low number), only the object you focus on wil be sharp, everything else in the frame will be blurry. To control exposure during filming you can use the exposure compensation settings in your camera (a lower number means an under exposed (darker) frame, and a higher number means an over exposed (lighter) frame). In photography you would usually adjust the shutter speed to control exposure, but as this is film the shutter speed remains fixed.
Originally I was going to shoot my main film using my DSLR. Unfortunately it needed repairs and I shot the film on my phone instead. It actually made the process of filming more streamlined as I recorded and edited the footage all on my phone. As my phone does not give my as much creative control like the DSLR does I chose to shoot on auto. For controlling light I used practical effects such as opening and closing curtains and using a reflector.
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