Aperture, Gain and ND Filters - Cinematography

In class, we have been doing some practical exercises using the camera which involved us changing the shutter angle, ND filter, aperture, gain and the focal length of the lens. These experiments were to show us how these things work and how focal length and aperture change the depth of field of the image.

My group used a Canon camera for these experiments. We had a sheet with twelve different set ups on it that we had to do in our groups of three. We each took turns at taking control of the camera and setting it to all the settings that were required. Each person had to frame up a mid shot of a person (subject) with an interesting background and go through each set up which consisted of three different focal lengths - wide lens (zoomed all the way out), mid length (zoomed half way in) and a long length (zoomed all the way in). The shot had to be a mid shot of the same subject at each focal length.

At each focal length, there were four images that needed to be taken, each with slightly different settings. Following is each of the four different settings that were required:

1. Shutter Angle: 180
    Gain: Low (0dB)
    ND Filter: 0
    Set aperture for correct exposure

2. Shutter Angle: 180
    Gain: Low (0dB)
    ND Filter: 1
    Set aperture for correct exposure

3. Shutter Angle: 180
    ND Filter: 2
    Adjust gain if image is too dark for acceptable exposure
    Set aperture for correct exposure

4. Shutter Angle: 90
    Gain: Low (0dB)
    ND Filter: 1
    Set aperture for correct exposure

Here are screenshots of my experiments:

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Unfortunately, I did not focus the camera clearly on my subject in the last four images (long focal length), so the footage came out looking too soft and there was no definition in the background to show the depth of field.

The gain affected the image by making it look grainy when it was set on medium and high gain. High gain was the grainiest. From this lesson, I learned that the gain should never be touched unless its really needed like at night time.

ND filters affected the light that was seen in the image. It dulled down the brightness of the glaring light (if you look in the corners of the images where the sky is, there is a slight difference in brightness) but it did not affect the light on the subject in the image.

The aperture affected the depth of field. As previously discussed in my post about aperture, if there is a higher f-stop (small lens opening) then the depth of field is deeper and if you use a lower f-stop (larger lens opening) then the depth of field is shallower. Unfortunately, because of my lack of focus (on the camera) the images can not be properly compared.

I have learned heaps of different things by doing this exercise and I plan on doing this exercise again, so I am able to practice using the camera and this time I will hopefully remember to use the focus on the camera. Come on, Lee - FOCUS!