Motion Capture Markers Explained: Types, Sizes & Applications
Optical motion capture has come a long way since its early days. As the technology evolves, so too do the design, requirements, and application methods of reflective motion capture markers used in passive motion capture systems.
Types of Mocap Markers
Many different marker types are available, and the choice depends heavily on your intended use. For this reason, many studios combine different types or adopt a hybrid setup.
Screw-in Markers
Screw-in markers offer excellent versatility, available with a hard or soft, flexible base. Hard, spherical options come in various sizes to suit your capture volume setup perfectly. Traditional taped markers and the newer coated "pearl markers" work well for fingers or low-impact motion capture. However, they're not ideal for action shoots involving landings on crash mats. Similarly, foam-based screw-in markers should be avoided for high-impact applications due to their lower durability and need for replacement if damaged.
The separate elements allow for easy replacement of reflective markers during a shoot.
Soft Markers
Soft, integral markers are very popular. Among various providers, the X-base markers from the US tend to be commonly used. This soft, flexible marker with a hook-and-loop base works well with Velcro-compatible suits, gloves, hats and props. The X-base offers good adhesion due to its larger surface area, and its base "arms" allow it to contour around the body, hands, and objects. The base can be easily cut for smaller objects like shoes and props.
Soft markers are ideal for action and stunt shoots with high impact. The pliability of the marker varies between companies and sizes. For example, the discontinued 19mm markers were solid rubber, whereas the 14mm markers are hollow and therefore much softer. A new style of soft integral 9mm X-base/rectangle-base has recently been introduced.
Markers Sizes: Which Should You Use?
Typically, the standard size for full-body markers is 14mm. Larger markers are ideal for larger volume setups as they enable the cameras to capture them more easily. For the same reason, spherical markers are now favored over hemisphere-shaped markers, although the latter are still used in situations with ample camera coverage.
Smaller markers, typically ranging from 9mm to 14mm, are used for finger capture depending on the specific capture needs and camera setup.
Optical Markers for Finger Capture
There are many methods for finger capture, with or without gloves. Again, the choice depends on your system size, configuration, and capture needs. Passive markers are typically affixed with adhesives (glue or tape) or attached to Velcro-compatible gloves using wraparound or standard Velcro-backed designs. Reflective markers may also be used in conjunction with markerless glove technology.
Optical Markers for Face Capture
For optical facial capture, small hemisphere or fully spherical options are available in sizes ranging from 3mm to 4mm.
Mocap Marker Solutions
With evolving shoot requirements, it's important to have flexible options that work for you. Mocap Ready offers a range of affordable solutions – from retaping services to motion capture markers and bespoke products. For more information, please get in touch.
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