Interchangeable Lenses versus Built-in Zoom: What Filmmakers need to Know

Despite the ever-changing, ever-growing camera?market where photographers and videographers alike salivate at the latest innovations, one could say that the still and video camera market comprises two types of cameras: those with built-in lenses (fixed-lens cameras), and cameras compatible with interchangeable lenses (sometimes called system cameras, if they belong to a specific camera-lens ecosystem). There are inherent?advantages in each design, and it is very possible that one of these types of cameras suits your image-making style better than the other. So, let¡¯s take a look at a few diverse scenarios and consider how these different camera options fit into those situations, starting with the basics and working our way up.

Interchangeable-lens camcorder
Consumer Video
For a long time, the consumer video market segment has been ruled by fixed-lens video cameras, also called camcorders, with an iron fist. For the average consumer, the advantages of this design are fairly obvious. First, because the lens is built into the body, the camera can be smaller, lighter, and shaped appropriately to fit into an average human palm; hence, the so-called ¡°palmcorder.¡± The simple design requires no lens changes and no laborious manual setups. Everything about these camcorders is ¡°get up and go.¡± I could say it¡¯s as easy as ¡°set it and forget it,¡± but that would be false; using a consumer camcorder is easier than that because nothing really has to be set in the first place. You just turn the camera on (sometimes by simply opening up the screen) and press the Record button as soon as you feel the need to capture the moment. Once you are rolling, the camcorder does the rest, adjusting exposure to maintain a good image and audio levels to make sure that sound is captured properly.

Example of a classic ¡°Palmcorder¡± ¡ªthe Panasonic HC-WX970K 4K Ultra-HD Camcorder
The lens, despite its size, can usually cover a very large zoom range. In the early days of the consumer camcorder, manufacturers would wage ¡°zoom¡± wars to outdo each other in zoom-range specs, requiring large stickers on cameras imprinted with marketing fluff like ¡°600X ZOOM,¡± followed by a footnote explaining what that meant. Having a decent zoom range is crucial, because it allows you to capture important moments from most distances, ranging from a few feet away to fifty auditorium rows away. The lenses that are built into consumer camcorders will also provide autofocus, an absolutely invaluable tool that can be found on basically any consumer camcorder with a focusable lens.

The Canon EOS Rebel T5 is a DSLR that shoots video while using Canon¡¯s large selection of lenses.?
So, even though it would seem that fixed-lens camcorders are a shoo-in for everyone, interchangeable-lens cameras are becoming more prominent on the market. As camera technology has advanced, convergence between the stills and video world became inevitable. DSLR cameras, once the archetype of the consummate professional stills photographer, have become more advanced in their ability to create cinematic-looking video and, at the same time, are far less expensive. While it may be a fool¡¯s errand to discourage the average consumer from using their DSLR for everyday video because of the massive aesthetic appeal, fixed-lens cameras will get the job done much more easily. This is especially true for capturing impromptu moments that may never happen again. No one wants a cherished moment to be missed because you couldn¡¯t change lenses in time, or couldn¡¯t get the shot precisely in focus. Put simply, for most consumers, a palmcorder-type camera may be the most functional. Yes, learning to shoot beautiful video on your DSLR is a valiant undertaking. But don¡¯t lose sight of what¡¯s important¡ªgetting the shot.
Professional Video
What a great segue into our next segment! Now that we are outside of consumer video, things get a little more intense. Most professional videographers are in a similar situation to consumer videographers. They need to get the shot without compromising visual quality; however, they get paid to do that. When there is cash on the line, you had better get the shot. No shot, no cash, capisce? Getting paid is the defining characteristic between Professional and Consumer video. Regarding professionals, their choices and budgets can vary widely. As professionals, they have enough experience to decide what is right for their workflow.
Fixed-Lens or Interchangeable-Lens Route?
The ¡°all-professional¡± camcorders are huge shoulder-mounted beasts, which can cost more than luxury cars, ensuring that only people who are trained to use such a tool can possibly obtain one. They have controls for nearly every conceivable aspect of video image quality, and at the forefront of all that, they have a lens mount¡ªnot just any lens mount, but a B4 lens mount. The B4 mount is the de facto standard for professional productions, especially for Electronic News Gathering (ENG) and documentaries, because of its well-touted versatility. Lenses for the B4 mount vary greatly from ultra-wide specialty lenses to super-telephoto box lenses that probably have enough range to observe alien life on other planets. For a while, Zeiss even made a line of fast cinema primes for the B4 mount (used in the production of the movie Zodiac, which was shot completely digitally), but we will talk about cinema later. Lenses on these cameras can cost even more than the camera itself. They are state-of-the-art, super-sharp, wide-aperture lenses with precise manual controls, and can have built-in servos for electronic control. The sheer versatility and robustness of these lenses and the B4 system could easily go beyond the scope of this article. To sum up, professionals who have access to a B4-mount camera know chances are good that there is a lens that fulfills their focal-length needs, regardless of how extreme. If there is a shot to be had, a B4 camera can get it. ?

The Sony HDW-790 is a professional HD camcorder with a B4 mount for attaching a wide variety of lenses.?
Fixed-lens camcorders are more limited, and they usually inhabit the lower-budget segment of the professional video area. Although I say ¡°lower budget,¡± these camcorders can easily cost several thousand dollars. While their unified design is compact compared to B4-mount camcorders, they are by no means simple cameras. Housed within their chassis is usually a bright and powerful zoom lens, which can cover approximately 90% of what normal productions require. For almost anything else, conversion lenses that modify the image can be used, at the possible expense of a slight drop-off in image quality.

With its built-in lens,?the Sony PMW-300 is a powerful option for event videographers.?
Although fixed-lens pro camcorders might not have all the lens options of a B4-mount camcorder, their unified design can have other advantages for the professional. One of those advantages is weather sealing. While not available on all models, because there is no lens-mount space for the elements to invade, you can expect fixed-lens camcorders to be better protected against the elements¡ªgenerally, for seriously inclement weather, a rain cover or other protection is highly recommended, regardless of what camera you have. Other practical advantages are size, weight, and ergonomics. Most camcorder designs hide a large portion of the lens inside the camera body. Because manufacturers are not restricted to designing a lens that fits on an external mount and over a sensor that¡¯s close to the front end of the body, they can make a larger lens and move the sensor block farther back into the body. This kind of design balances the weight of the camcorder very well, making it ideal for handheld shots. Many event videographers rely on camcorders with a fixed lens because those lenses have large zoom ranges, yet will still fit right in the palm of one hand, so their other hand can be used to adjust the camera lens and settings. Either way, the pros know what they need to get the shots they require, and either type of camcorder will usually be able to do most jobs.
Cinema/Digital Film
I will do my best to simply shine some light on the benefits of fixed and interchangeable-lens cameras in this field. Like the pros in the previous segment, and consumers in the segment before that, cinema is also about getting the shot. The major difference here is that those shots are carefully planned to a ¡°T.¡± With that planning, lens options that were not previously practical are now opened. Directors of Photography (DPs) can carefully choose how to frame their shots as needed, and with some notable exceptions, will choose one of many lenses to capture that shot. For the last few decades, and even more recently, the ARRI PL-mount system has been the most common choice of cinematographers worldwide. The benefits of a fixed-lens camcorder are rendered moot in the face of the lens options provided for the PL mount. PL-mount lenses are extremely robust, precise, and expensive. High-end cinema lenses are generally owned only by rental houses, studios, and the few who can afford them. This choice of lenses offers DPs artistic precision in the ways that they render images.?

Sony¡¯s CineAlta cameras like the PMW-F55 are completely modular and accept PL mount lenses.?
Fixed-lens camcorders simply cannot match the level of artistic choice provided by a range of cinema lenses. But for those who cannot afford a city block¡¯s worth of production equipment, where do they turn? That¡¯s an easy answer: DSLRs and large-sensor mirrorless cameras. These cameras offer similar lens versatility of higher-end setups without the gargantuan cost. This opens up similar levels of artistic choice to an entire world of people. Some mirrorless cameras can record 4K-resolution video and can even be adapted for use with PL-mount lenses! So, let¡¯s not ignore the fact that cinema is about the artistic value. Not everything is set in stone. Perhaps someday, fixed-lens camcorders will carve out a larger niche in the artistic community.

While it doesn¡¯t have interchangeable lenses, the Panasonic DVX-200 breaks the mold with its cinematic images.
Go ahead, shoot your family videos with a DSLR, or events with a large-sensor cinema camera and a PL lens. An entire article can be devoted to how imaging technologies are converging and how the rules that governed different sectors of the video business no longer apply. What it really comes down to is what makes you feel most comfortable as far as your ability to accomplish your task¡ªto get that shot!