The simple addition of a Matte Box can turn virtually any camera into a professional-looking camera rig. For DSLR/mirror-less camera owners, sometimes looking professional is what the job requires. However, a proper matte box serves more than just making your camera look good. When used properly, a matte box can greatly improve the final image.
What is the Purpose of a Matte Box?
A staple in cine-style shoots is the ubiquitous Matte Box. The foremost purpose of a matte box is to control light entering the lens; thus, virtually eliminating lens flares. Lens flares occur when superfluous light reaches a camera lens’ front element and reflects or bounces within the lens elements and between the image sensor. To combat reflected light, lens manufacturers apply multilayer coating materials such as Magnesium fluoride (MgF2), silicon monoxide (SiO), or aluminum oxide (AI2O3) among other lens coating options to a lens’ front element. Nevertheless, lens flares remain prevalent even on lenses with the latest in coating technology.
Therefore, a matte box is placed in front of the camera lens to block and/or prevent stray light from hitting the lens. Adjustable top and side flags can be used to aid in the shading process.
An equally viable feature a matte box provides is filtration capability. Filters serve the purpose of modifying light as it enters the lens. Appropriately placed behind the matte box housing and in front of the camera lens, filter stages are designed to accommodate multiple filters of varying sizes. Depending on the filter, the filter stage may be required to rotate in order to achieve the filters purposed effect. And, in some scenarios, multiple filters may be needed to achieve the desired look.
The Challenge of Choosing a Matte Box
Although simple in appearance, choosing the right matte box can seem challenging due to the various sizes, features and limitations of each unit. For example, ARRI has 9-individual matte box solutions designed to fit an ARRI ALEXA when using a Leica Summilux-C 18mm Prime Lens; Chrosziel offers 15-solutions; and Bright Tangerine offers 5-solutions; not to mention the myriad of other Matte Box manufacturers. Replace the Leica Summilux-C 18mm prime lens for a Cooke S4/i 14mm prime lens and the matte box options would diminish.
Why the sudden change when the lens changed? All the above mentioned matte boxes are designed to accept lenses up to at least 18mm when shooting in Super 35. However, when a lens wider than 18mm is introduced, in this case a 16mm lens, some matte boxes will cause the lens image to vignette. The vignetting is caused by either the filer tray being too small or the matte box housing not being wide enough.
One-Size-Fits-All Matte Boxes
To combat the challenge of choosing a matte box, some manufacturers have designed and manufactured a one-size-fits-all matte box. This type of matte box is designed to fit from compact-sized cameras, e.g., Blackmagic Pocket Cinema Camera, Canon 5D MKIII, to full-sized cine cameras, e.g., ARRI Alexa, RED Weapon. The main caveat being size and weight.
Designed to accommodate lenses with an outer diameter of up to 150mm and larger-sized 5.65×5.65 filter trays, a one-size-fits-all matte box can become too big and heavy for smaller camera set-ups, e.g., Steadicam and Drone applications.
The Anatomy Of A Matte Box
Like a painter with many brushes, matte boxes come in many different shapes and sizes designed to fit a need. To properly choose a right matte box, it is important to understand the key components of a matte box.
Following is a brief overview of all the elements needed in a well designed matte box:
Matte Box Housing
Available in 4:3 or 16:9 format, with the latter being the most common, the housing’s primary purpose is to prevent stray light from entering the camera’s lens. Composed of either ABS or carbon-fiber material, the internal housing should employ a matte-finish to diffuse reflective light.
Placed in front of the matte box housing, masks are an additional feature designed to limit stray light from entering the camera lens. Masks reduce the matte box opening size to the lens’ appropriate focal length image area; thus, limiting lens flares. As lenses often change during a shoot, masks are designed to be mounted and removed quickly.
Top & Side Flags
Affixed to a matte box housings’ pivot mechanism, top flags (commonly referred to as French flags) and side flags are additional tools designed to limit stray light from entering the camera’s lens. The top flag, composed of a single piece, covers the length of the matte box housing. The side flags, composed of adjustable sleeves, cover the height of the housing. Used in combination, each flag can be adjusted individually to prevent light leakage while controling lens flares.
Directly behind the matte box housing sits the filter stage mechanism designed to hold filters in their respective trays. While two-stage systems are most prevalent, filter stages are available from as little as one stage up to four stages; with some higher-end matte box systems offering modular filter stages, i.e., the ability to add or remove filter stages.
Certain filters require to be rotated to achieve their desired look. As such, rotating filter stages are a necessity to any matte box system.
Clamp-on & Rods
Matte Boxes have two options for support: Clamp or Rods.
Clamp-on matte boxes are usually lightweight and primarily designed to mount directly onto a camera’s lens. Due to its lightweight build, they are often preferred by handheld camera operators.
Heavier-duty matte boxes are primarily designed to mount directly onto 15mm or 19mm rods.
It goes without saying that every second counts on a film shoot. A swing-away bracket aids in time savings by facilitating faster lens changes. Rather than having to remove the matte box to get access to the lens, the swing-away bracket allows the matte box to move forward and swing away from the lens; saving valuable time.
A matte box’s rear opening diameter is usually larger in size in order to accommodate most lenses. Intermediate rings are used between the rear opening and the lens to prevent light leakage. Although less elegant, neoprene donuts can be used as an alternate to intermediate step-rings.
A rubber bellows serves the dual purpose of being an intermediate step-down ring while simultaneously being capable of holding a 138mm round filter. The most common filter in a rubber bellows is a Polarizer. Rubber bellows are designed for matte boxes with rod support and cannot be used with clamp-on systems.