Cinematography, videography, photography: ultimately, it is about showing something in a way that hasn’t been seen before. How you achieve this is a combination of framing, exposure, and post effects. It is the Digital Age—you can create just about any effect you want if you have the time, tools, talent, and software, of course. You can also hire someone to pull it off for you. While either of those options are valid, as you probably know, there is more than one way to skin a cat, so the focus of this article will be practical lens effects and what they bring to your project. I’m going to avoid discussions on polarizers and diffusion filters, since we have covered them many times over.
I’m a big believer in practical effects. I think that practical effects add to your film in ways that effects generated in post don’t. Certainly, practical effects help the actors know where they are and what is going on. But why create effects in the lens instead of at home on your computer? In-camera effects aren’t going to help the actor and, once you’ve made the effect, it can’t be removed. But here is the thing, an in-camera effect is something that acts on your image, and acts on you. The lens is actively creating the image; post processing just interpolates pixels that aren’t there, and while post effects are darned amazing, there is something satisfying and different when you use lenses and optical filters to create your effects. Those in-camera framing choices that are influenced by the lens choice affect the composition, the placement of actors, or position of elements in your shot. They affect you as you make that choice, and that choice ends up affecting the audience that watches it. For example: racking focus between two characters has a different feel than a shot where both characters are in focus.
As with any effect, moderation is usually the order of the day, because over-aggressive use of an effect can distract your audience and take them right out of your film. But, as with all things there are exceptions, and sometimes an aggressive effect is just what is called for.
Split Diopter and Tilt/Shift Lenses
If you are a Brian De Palma fan, then you are well acquainted with his use of the split diopter, which alters the focus plane over one part of the lens. This allows you to keep two significantly different areas of your frame in focus, even when one part of your frame is deep background and the other is close-up. There is often a clear demarcation of where the filter is, literally half of the filter ring holds an optical element while the other half is empty. Often, filmmakers will try to hide this line in the frame so it is less noticeable, and shooting with a wide-open f/stop can help, because the blurred area where the diopter ends becomes more visible the more closed-down your iris is. The split diopter is usually used to expand the range of things that are in focus; however, the obvious inclusion of this blurred line can be unsettling to your audience and used to create an “intellectual montage” of increased conflict, or perhaps a separation, on some level, between the actors in frame—even though they are both in focus.
Tilt/shift lenses (also known as swing/tilt) can be used in much the same way, to increase the range of focus you have, beyond what you can accomplish using depth of field alone. It is important to note that tilt /shift lenses work differently than split diopters, by allowing you to slant the focus plane as it recedes, so you don’t get a blurred line of focus, even when stopped down. Schneider has introduced tilt/shift versions of its full-frame prime lenses. Lensbaby lenses brought shift/tilt lenses to the masses, so to speak, with its first lens being little more than an optic with Waterhouse stops on a flexible tube and a lens mount. This “low-tech” tilt/shift lens has since spurred more polished lens creations that are certainly worth playing around with.
Fish-Eye and Rectilinear Wide-Angle Lenses
I must admit that I love taking stills with a fisheye lens—just a little adjustment to the framing can completely change the feel of the shot. Perhaps it stems from my days of shooting music videos that I especially love how the effect magnifies, the closer the subject is to the lens. I’ve been quite pleased shooting stills and 4K video with the fisheye lens from the Lomo Experimental lens kit on my Panasonic DMC-G7, much to the chagrin of my daughters when I shoot them in close-up. I know there is usually a huge vignette, but that doesn’t have to mean you can’t use a fisheye for your movie.
Remember: it is merely a tool, and you choose when it is the right time to use it or not. I really do enjoy wide-angle distortion, even if it isn’t the fish-eye effect. Used in conjunction with the actor’s movements, you can get a tremendous effect, and it is a powerful tool that, visually, can bring expression and impact to your film. We are all accustomed to the wide-angle lens effect and the distortion it can bring to your shot. However, there is another kind of wide-angle lens, the rectilinear wide angle lens. These lenses are extremely wide, but minimize the fisheye effect. Very useful for architectural photography, the rectilinear lens shows us the world in a far different way than we are accustomed to seeing wide-angle shots on the screen—yet another way to make your images more compelling and to engage your audience.
Lens manufacturers go through a great deal of trouble designing their lenses with what is often referred to as “pleasing” or “naturalistic” bokeh. This is often accompanied by designing an iris that produces a round aperture. There are, of course, lenses that don’t follow this ideal—Zeiss Super Speed lenses, in the 1990s, had a triangular iris, producing interesting out-of-focus highlights that were, in many ways, a signature of those lenses. The Petzval lens is noted for producing swirly out-of-focus backgrounds. What can you do with this in a video setting? Remember, your images are (hopefully) affecting your audience emotionally or intellectually. Lighting ratios, contrast, wardrobe colors, art direction—they all work in concert to impact the viewer. So, too, can bokeh in an image affect the viewer, and it isn’t just naturalistic, round, out-of-focus highlights that are in vogue these days. The swirly backgrounds of the Petzval lens bring a certain unreality to an image that in a still photo can provide interest but, in a video, may bring a dreamlike feeling or create a sense of discomfort seeing the world portrayed this way. Lensbaby is present here also, with its Twist 60 Optic.
One other aspect of the Petzval and Lensbaby lenses is that they are designed with replaceable Waterhouse stops. Just as with an adjustable iris, the Waterhouse stop controls your exposure, but an odd side effect is that out-of-focus highlights will take on the shape of the Iris or Waterhouse stop. This provides endless possibilities for in-camera image manipulation and fun. Granted, you can accomplish the effect yourself with a regular lens and shapes placed close to the front lens element, but the Lensbaby is designed with magnetic Waterhouse Stops, and you can purchase or make your own Waterhouse stops with different shapes or patterns for the Petzval Lens. Perhaps a rack to an oddly shaped out-of-focus background as a scene transition, to provide a foreshadowing of unfolding events? The effects are yours to create.