This post is by Daniel Brockett from Blog – HD Video Pro
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There are so many lens choices possible in 2020. Not only lens brands and models, but different types of lenses for different functionality.
Let’s talk lenses. In 2020, we have many, many choices in lenses, especially depending on the camera you shoot with. Our main digital cinema cameras are the Canon C300 MKII and the Canon C200. Choosing the best lenses for our camera should be relatively easy and fairly simple, right? Somehow, the more I mull it over in my head, the fuzzier the right choices become.
Lenses are best chose for the types of shoots that you mostly
. I’m a terrible illustrator, but imagine if you will a triangle. One side of the triangle is labeled cost. One side of the triangle is labeled quality. The last side of the triangle is labeled function. This triangle is sort of like the famous “Triangle of Buying Choice” where the sides of the triangle are labeled “Speed, Quality, Cost” and, as the saying goes, pick any two. You really can’t have all three; you have to compromise in at least one area. My lens triangle is somewhat the same, except I don’t know if you can even have two of the three. At times, it feels like you can only have one choice.
Case in point, lenses for our digital cinema cameras. Let’s take a look at some of the choices we have in the famous Canon EF mount, probably the most popular camera mount available today for digital cinema and mirrorless cameras overall.
Still Camera Lenses
These could be Canon EF and EF S models, but there are many other types and focal lengths available, obviously from third-party manufacturers.
In the case of Canon, I’d term these lenses hybrids because they take aspects of still lenses, cine lenses and B4 broadcast 2/3” lenses and combine them into one lens suitable only for S35 sensors. These are the Canon CN E 18-80mm t/4.4 compact servo lens and the Canon 70-200 t/4.4 compact servo lens. These aren’t still lenses, but they aren’t proper cinema lenses with hard stops and long focus rotation like Canon’s CN E Primes have either. They’re designed for digital cinema cameras, though, and cover an S35 sensor frame but have a servo control for zooming that isn’t typically found integrated into the lens, it must be obtained from third-party zoom controllers with separate external motors and power supplies.
Most of us know what a cine lens is, but some of the common characteristics are that the lenses have hard stops, markings on both sides of the lens for operator and ACs to view and often the markings glow in the dark for operating in dim environments. Cine lenses have all manual operation and typically have a focus rotation that’s long, 200 to 300 degrees for smoother operation with follow focus units, often controlled by a focus puller. It’s interesting today that in this category, we have low-end cine lenses like the Rokinon Cine DS, cine converted still lenses that cost a few hundred dollars apiece, all of the way up to the top of the line cine lenses by Zeiss, Cooke, Leica, Angenieux and many other manufacturers that can cost tens or even hundreds of thousands of dollars.
If you’re a new digital cinema camera owner, or even a mirrorless or lower end digital camera owner, you have many, many choices for which lenses will function best for you in your shooting situations.
Run & Gun/Event/Documentary Shoots
Any of the three categories above can be used in this situation. But as you work through it, a few truths become self-evident. For these types of shoots, the most important factors are often size and weight. A huge, heavy cine lens will limit a single camera operator more severely than a smaller, lighter weight lens. Shooting this type of coverage with prime lenses is definitely possible, but you may find yourself missing certain shots without a zoom lens. I’ve shot documentary coverage with zoom lenses when I’m running around literally documenting an event as it happens in real time, but also covering an event like this in very, very low light where a fast prime lens is superior to any zoom because primes are typically so much faster because they have more light-gathering capability. Nobody wants to shoot low light and have to crank the gain in their camera very high because of being saddled with a slow zoom lens.
Interviews can definitely be shot with any lens in any of these categories. Autofocus technology can be very valuable when shooting interviews, especially if you don’t have a camera assistant pulling focus for you. S35 and full frame sensors have a much shallower depth of field than the smaller size sensors we used to use in 2/3” broadcast cameras. Combine that relatively shallow depth of field with talent that rocks or moves back and forth in the frame, and if you’re shooting with manual focus, it can be easy to end up with slightly out of focus footage if you can’t track their slight forward and backward movements perfectly. Even if you have a large enough monitor to judge focus, which you may or may not, or a good EVF where you can definitely judge focus, it can be exhausting to follow focus continuously on your subject over a one- or two-hour-long interview.
As cameras have moved from SD to 1080 to 4K and now 6K and 8K over the past decade, it’s also becoming more difficult to actually see if something is in sharp focus on a 1080 display, which is what most EVFs and smaller monitors are capable of. There are no 7-inch 4K, 6K or 8K native displays, so what you see isn’t necessarily what you are getting. Footage that looks perfectly sharp on your small monitor or EVF, when played back on a larger screen, can often be slightly soft and out of focus. For this reason, I value autofocus and face/eye detection for interviews. Unfortunately, this limits you to still lenses or hybrid lenses. None of the digital cine lenses on the market at this time have autofocus, although we believe that AF for pro cine users is coming in the near future.
Depending on how often you shoot narrative, you may or may not typically work with camera assistants and focus pullers. If you do, it can be a pleasure to shoot with a good AC and or focus puller. AC/focus pullers need, want and prefer cine lenses with longer focus scales, markings on both sides of the lens, hard stops, etc. Focus pullers don’t like working with still or hybrid lenses because they simply aren’t set up correctly to work in the way that focus pullers are used to working. Still and hybrid lenses typically have focus rotations that are too short and the lenses lack hard stops, making repeatability in hitting focus marks impossible and the physical size of most still and hybrid lenses aren’t conducive to having a crew working on the camera.
Personally, I think that the latest developments in AF technology are becoming so good that soon we’ll see professional level autofocus systems for higher-end digital cinema cameras and PL mount lenses. As of today, though, that technology hasn’t quite yet arrived, so my prediction is that pro cine AF is something to look out for in the near future.
Focus By Wire Or True Manual Focus?
Lenses were all manual about 15 to 20 years ago other than a few consumer AF lenses. Even still photo lenses were made out of steel, aluminum and brass; the focusing controls were smooth and mechanically linked to the lens. Same with aperture controls to open or close the lens’s iris, they were mechanical. Sure, still lenses had clicks to differentiate ƒ-stops for still photographers while cine and pro video lenses had clickless aperture controls so that the lens’s iris could be subtlety opened or closed during a shot without the exposure change having steps.
At some point, when better AF became the norm for still lenses, mechanical focusing evolved as focus by wire became the norm. What is focus by wire? For most AF lenses today, when you turn the focusing ring there’s a digital chip/mechanism in the lens that receives the focusing input from the focus ring rotating and turns it into a digital signal that’s fed to a small circuit board in the lens. The impulse triggers the focusing motors to move and focus the lens elements. The problem for us is, all of this analog to digital conversion input has a slight latency or delay, and the impulses are merely two way, as in the rotation impulse moves the focusing element forward or backward. So any fine feel that you had in focusing a mechanically focused lens is now gone. No repeatability, no mechanical feel. Manually focusing on today’s lenses ranges from impossible to merely terrible.
Same with aperture control. Lenses used to have the iris mechanically linked to the aperture wheel on the lens, so you turned the aperture ring and the iris closed or opened accordingly. Today, many still lenses don’t even have an aperture ring. They’re controlled electronically by a wheel on the camera body. For manual operation, still lenses have actually become much worse over the past decade or two. AF technology has become noticeably better but manually focusing has become pretty bad, making still lenses a poor choice when you want to control focus or smoothly ramp the aperture as your character moves from dark to light or vice versa.
What My Lens Choices For 2020 Look Like
We already own a dozen Canon EF and EF S still lenses. Some really great ones like the EF 70-200mm f/2.8 IS II, and some not so great ones like the EF S 17-55mm f/2.8 IS. The former is a pro-level telephoto zoom that’s ruggedly built and makes beautiful footage that looks as good as footage coming from cine lenses that cost 10 times more. On the latter, the build isn’t very good, the dust sealing is terrible, the AF is much slower and clunkier and, worst of all, because it’s only designed to cover the APSC 1.6X crop, vignettes pretty badly with the 1.5X crop S35 sensors in the two cameras we shoot with most.
Lately, I ‘ve been shooting interviews and some lifestyle b-roll footage with our three Canon still primes, the EF 28mm f/1.8, 50mm f/1.8 STM and EF 85mm f/1.8. All cover full-frame sensors, so there’s no vignetting on our S35 cameras, and all look good and match fairly well as far a color and lens coatings. The only downside of them is when we try to use them for manually focusing, creatively when shooting b-roll, their focusing is all focus by wire and the focusing rotations are ridiculously short, making manual focusing, even using Canon’s handy focus assist function, a nuisance.
I’ve shot with and reviewed the Canon CN E 18-80 and 70-200 t/4.4 compact servo hybrids here for HDVideoPro. They’re great lenses and are very useful for run and gun and documentary work. But for manually focusing, they have no hard stops and because they support AF and IS, are both focus by wire.
I like shooting with primes because they’re generally smaller, lighter and much faster than zoom lenses. For situations where we’re going to be shooting talent, functions, dance, tabletop, performance or narrative, primes make a lot of sense. Now the dilemma is, which primes to invest in? Stay tuned for more details in an upcoming blog post where we’ll delve into the many choices that are available for an EF mount cine prime.