In the 1970s and 80s – back when dinosaurs grazed under the el on Wabash – I worked as a camera assistant on episodic tv shows and commercials. We mainly shot on 35mm film and images were composed within an image area known as TV Safe Action. TV Safe Action had an aspect ratio of 4:3 and measured approximately 18mm X 14mm.
We used a simple rule of thumb to determine the distance needed to achieve the field of view for a head and shoulders closeup at any focal length: divide the lens focal length by ten and express the result in feet and inches. For example, 45mm÷10 = 4.5 = 4 feet 6 inches or 150mm÷10 = 15 = 15 feet. Within a given format, this simple formula will give you the same field of view at the point of focus.
We used this mainly to match image size between closeups, but it was also useful for placing the slate so that it could be easily read by the editor. It is also a useful baseline for extrapolation: halve the focal length or double the distance and you get a field of view twice as high and wide. Conversely, double the focal length or halve the distance and you get a field of view that is half as high and wide.
Notes on the illustrations –
I used the Field of View and Preview function on David Eubank’s pCAM Pro to generate these screen grabs. pCAM Pro is the industry standard, a truly indispensable cinematography and photography tool. David has made constant improvements to the interface and ongoing updates to the database since the introduction of pocketCAM for Palm devices in 1999.
Each set of illustrations show the field of view for 25mm @ 2’6”, 50mm @ 5’ and 75mm @ 7’6” for the designated format.
If the illustrations were actual photographic images with foreground and background elements, wide angle and telephoto effects would come into play. Nonetheless, within each format, the field of view at the point of focus is consistent.
The illustrated field of view is the area within the light blue background.
35mm Film – SDTV TV Safe Action
image area – 18mm X 14mm
aspect ratio – 4:3 / 1.33:1
Lumix GH5
image area – 17.3mm X 13mm
aspect ratio – 4:3 / 1.33:1
35mm Film – 1.85:1 Projector Aputure
image area – 20.95mm X 11.32mm
aspect ratio – 1.85:1
Lumix GH5S
image area – 18.8mm X 10.6mm
aspect ratio – 16:9/1.78:1
35mm Film – Super 35
image area – 24mm X 13.5mm
aspect ratio – 16:9 / 1.78:1
Arri Mini HD
image area – 23.76mm X 13.370mm
aspect ratio – 16:9 / 1.78:1
Panasonic VariCam 35
image area – 23.04mm X 12.96mm
aspect ratio – 16:9 / 1.78:1
Canon 7D Mark II
image area – 22.4mm X 12.58mm
aspect ratio – 16:9 / 1.78:1
8mm Film – Super 8
image area – 5.7mm X 4.22mm
aspect ratio – 4:3 / 1.33:1
35mm Film – VistVision 8 Perf
image area – 37.72mm X 24.92mm
aspect ratio – 1.51:1
35mm Film – Full Aperture
image area – 24.92mm X 18.67mm
aspect ratio – 4:3 / 1.33:1
35mm Film – 2X Anamorphic
image area – 42.62mm X 17.78mm
aspect ratio – 2.40:1
