One of the reasons we got our new FS7 video camera was for the large sensor which creates a shallow depth-of-field. This means we can focus selectively. Keep the background out of focus, not distracting during interviews. Really guide the viewer’s eyes to where we want them to look. The MetaBones lens adaptor we use helps in this respect as well: it makes the Super-35-sized sensor act as a full-frame 35mm sensor which is the size of 35mm slides. That’s even larger than classic movie film. The missing link to achieving super soft and creamy backgrounds was a nice wide-aperture prime lens.
Of course a lens is key to creating a particular “look” on photos, film and video. For shallow depth-of-filed one needs a large aperture (low F-stop) lens. The lower the F-stop, the larger the hole through the lens and therefore the depth-of-filed is shallower; that’s the nature of optics. An F1.2 or F1.4 lens has a significantly shallower depth-of-field than a lens that can open up only to F4 which is what our zoom lens is capable of.
Long story short: we got a 50mm F1.4 prime lens for our camera and it makes great pictures. It is an absolute must for interviews and it works great for much other shooting. (We actually got the cinema version of this lens that’s rated at T1.5, has follow-focus gears, no click stops on the iris ring, and is matched to other Samyang cine lenses. All these features make this a professional cinematography lens.)
This sample was shot with the new lens and it demonstrates the last essential piece of the puzzle: a variable-density filter. A large aperture (low F-stop) lets in a lot of light, but if you’re shooting outside where there is a lot of light and you don’t want to close down the iris (and lose that shallow depth-of-field), you need a neutral density filter to cut the light. A continuously-variable ND filter lets you dial in the precise exposure while keeping your lens wide open. In other words, use the ND filter for exposure while you use the lens’ F-stop to control the depth-of-field. That’s what makes our FS7 Mark II so special. The Mark II has a built-in continuously variable filter that can even be used for auto-exposure. So we have absolutely all the tools we need to control exposure and depth-of-field independently of each other and the resulting images are fantastic. (Note that the video sample above was shot and is posted in 4K [2160p]!)